CISCO WS-C2950-12, Catalyst 2950 User Manual

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Catalyst 2950 and Catalyst 2955 Switch Software Configuration Guide

Cisco IOS Release 12.1(22)EA5 July 2005

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Catalyst 2950 and Catalyst 2955 Switch Software Configuration Guide

Preface xxvii

Audience xxvii

Purpose xxvii

Conventions xxviii

Related Publications xxix

Obtaining Documentation xxix

Cisco.com xxx Product Documentation DVD xxx Ordering Documentation xxx

Documentation Feedback xxxi

Cisco Product Security Overview xxxi

Reporting Security Problems in Cisco Products xxxi

CHAPTER

Obtaining Technical Assistance xxxii

Cisco Technical Support & Documentation Website xxxii Submitting a Service Request xxxiii Definitions of Service Request Severity xxxiii

Obtaining Additional Publications and Information xxxiii

1 Overview 1-1

Features 1-1

Ease of Use and Ease of Deployment 1-2 Performance 1-3 Manageability 1-4 Redundancy 1-5 VLAN Support 1-6 Security 1-6 Quality of Service and Class of Service 1-7 Monitoring 1-8 LRE Features (available only on Catalyst 2950 LRE switches) 1-8

Management Options 1-9

Management Interface Options 1-9 Advantages of Using Network Assistant and Clustering Switches 1-10

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Network Configuration Examples 1-11

Design Concepts for Using the Switch 1-12

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Contents

Small to Medium-Sized Network Configuration 1-15 Collapsed Backbone and Switch Cluster Configuration 1-16 Hotel Network Configuration 1-17 Service-Provider Central-Office Configuration 1-20 Large Campus Configuration 1-21 Multidwelling Network Using Catalyst 2950 Switches 1-22 Long-Distance, High-Bandwidth Transport Configuration 1-24

Where to Go Next 1-24

CHAPTER

2 Using the Command-Line Interface 2-1

Cisco IOS Command Modes 2-1

Getting Help 2-3

Abbreviating Commands 2-4

Using no and default Forms of Commands 2-4

Understanding CLI Messages 2-5

Using Command History 2-5

Changing the Command History Buffer Size 2-5 Recalling Commands 2-6 Disabling the Command History Feature 2-6

Using Editing Features 2-6

Enabling and Disabling Editing Features 2-6 Editing Commands through Keystrokes 2-7 Editing Command Lines that Wrap 2-8

Searching and Filtering Output of show and more Commands 2-9

Accessing the CLI 2-9

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3 Configuring Catalyst 2955 Switch Alarms 3-1

Understanding Catalyst 2955 Switch Alarms 3-1

Global Status Monitoring Alarms 3-2 FCS Error Hysteresis Threshold 3-2 Port Status Monitoring Alarms 3-3 Triggering Alarm Options 3-3

Configuring Catalyst 2955 Switch Alarms 3-4

Default Catalyst 2955 Switch Alarm Configuration 3-4 Configuring the Power Supply Alarm 3-5

Setting the Power Mode 3-5 Setting the Power Supply Alarm Options 3-5

Configuring the Switch Temperature Alarms 3-6

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Setting a Secondary Temperature Threshold for the Switch 3-6 Associating the Temperature Alarms to a Relay 3-7

Configuring the FCS Bit Error Rate Alarm 3-7

Setting the FCS Error Threshold 3-8 Setting the FCS Error Hysteresis Threshold 3-8

Configuring Alarm Profiles 3-9

Creating or Modifying an Alarm Profile 3-9 Attaching an Alarm Profile to a Specific Port 3-10

Enabling SNMP Traps 3-11

Displaying Catalyst 2955 Switch Alarms Status 3-11

Contents

CHAPTER

4 Assigning the Switch IP Address and Default Gateway 4-1

Understanding the Boot Process 4-1

Assigning Switch Information 4-2

Default Switch Information 4-3 Understanding DHCP-Based Autoconfiguration 4-3

DHCP Client Request Process 4-4

Configuring DHCP-Based Autoconfiguration 4-5

DHCP Server Configuration Guidelines 4-5 Configuring the TFTP Server 4-6 Configuring the DNS 4-6 Configuring the Relay Device 4-7 Obtaining Configuration Files 4-8 Example Configuration 4-9

Manually Assigning IP Information 4-10

Checking and Saving the Running Configuration 4-11

Modifying the Startup Configuration 4-11

Default Boot Configuration 4-12 Automatically Downloading a Configuration File 4-12 Specifying the Filename to Read and Write the System Configuration 4-12 Booting Manually 4-13 Booting a Specific Software Image 4-13 Controlling Environment Variables 4-14

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Scheduling a Reload of the Software Image 4-16

Configuring a Scheduled Reload 4-16 Displaying Scheduled Reload Information 4-17

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5 Configuring IE2100 CNS Agents 5-1

Understanding IE2100 Series Configuration Registrar Software 5-1

CNS Configuration Service 5-2 CNS Event Service 5-3

NameSpace Mapper 5-3

What You Should Know About ConfigID, DeviceID, and Host Name 5-3

ConfigID 5-3 DeviceID 5-4 Host Name and DeviceID 5-4 Using Host Name, DeviceID, and ConfigID 5-4

Understanding CNS Embedded Agents 5-5

Initial Configuration 5-5 Incremental (Partial) Configuration 5-6 Synchronized Configuration 5-6

Configuring CNS Embedded Agents 5-6

Enabling Automated CNS Configuration 5-6 Enabling the CNS Event Agent 5-8 Enabling the CNS Configuration Agent 5-9

Enabling an Initial Configuration 5-9 Enabling a Partial Configuration 5-12

CHAPTER

Displaying CNS Configuration 5-12

6 Clustering Switches 6-1

Understanding Switch Clusters 6-1

Clustering Overview 6-1 Cluster Command Switch Characteristics 6-2 Standby Command Switch Characteristics 6-2 Candidate Switch and Member Switch Characteristics 6-3

Using the CLI to Manage Switch Clusters 6-4

Catalyst 1900 and Catalyst 2820 CLI Considerations 6-4

Using SNMP to Manage Switch Clusters 6-4

7 Administering the Switch 7-1

Managing the System Time and Date 7-1

Understanding the System Clock 7-1 Understanding Network Time Protocol 7-2 Configuring NTP 7-3

Default NTP Configuration 7-4

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Configuring NTP Authentication 7-4 Configuring NTP Associations 7-5 Configuring NTP Broadcast Service 7-6 Configuring NTP Access Restrictions 7-8 Configuring the Source IP Address for NTP Packets 7-10 Displaying the NTP Configuration 7-11

Configuring Time and Date Manually 7-11

Setting the System Clock 7-11 Displaying the Time and Date Configuration 7-12 Configuring the Time Zone 7-12 Configuring Summer Time (Daylight Saving Time) 7-13

Configuring a System Name and Prompt 7-14

Default System Name and Prompt Configuration 7-15 Configuring a System Name 7-15 Understanding DNS 7-15

Default DNS Configuration 7-16 Setting Up DNS 7-16 Displaying the DNS Configuration 7-17

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CHAPTER

Creating a Banner 7-17

Default Banner Configuration 7-17 Configuring a Message-of-the-Day Login Banner 7-18 Configuring a Login Banner 7-19

Managing the MAC Address Table 7-19

Building the Address Table 7-20 MAC Addresses and VLANs 7-20 Default MAC Address Table Configuration 7-21 Changing the Address Aging Time 7-21 Removing Dynamic Address Entries 7-21 Configuring MAC Address Notification Traps 7-22 Adding and Removing Static Address Entries 7-24 Configuring Unicast MAC Address Filtering 7-25 Displaying Address Table Entries 7-26

Managing the ARP Table 7-26

8 Configuring Switch-Based Authentication 8-1

Preventing Unauthorized Access to Your Switch 8-1

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Protecting Access to Privileged EXEC Commands 8-2

Default Password and Privilege Level Configuration 8-2 Setting or Changing a Static Enable Password 8-3

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Protecting Enable and Enable Secret Passwords with Encryption 8-4 Disabling Password Recovery 8-5 Setting a Telnet Password for a Terminal Line 8-6 Configuring Username and Password Pairs 8-7 Configuring Multiple Privilege Levels 8-8

Setting the Privilege Level for a Command 8-8 Changing the Default Privilege Level for Lines 8-9 Logging into and Exiting a Privilege Level 8-10

Controlling Switch Access with TACACS+ 8-10

Understanding TACACS+ 8-10 TACACS+ Operation 8-12 Configuring TACACS+ 8-12

Default TACACS+ Configuration 8-13 Identifying the TACACS+ Server Host and Setting the Authentication Key 8-13 Configuring TACACS+ Login Authentication 8-14 Configuring TACACS+ Authorization for Privileged EXEC Access and Network Services 8-16 Starting TACACS+ Accounting 8-17

Displaying the TACACS+ Configuration 8-17

Controlling Switch Access with RADIUS 8-17

Understanding RADIUS 8-18 RADIUS Operation 8-19 Configuring RADIUS 8-20

Default RADIUS Configuration 8-20 Identifying the RADIUS Server Host 8-20 Configuring RADIUS Login Authentication 8-23 Defining AAA Server Groups 8-25 Configuring RADIUS Authorization for User Privileged Access and Network Services 8-27 Starting RADIUS Accounting 8-28 Configuring Settings for All RADIUS Servers 8-29 Configuring the Switch to Use Vendor-Specific RADIUS Attributes 8-29 Configuring the Switch for Vendor-Proprietary RADIUS Server Communication 8-30

Displaying the RADIUS Configuration 8-31

Configuring the Switch for Local Authentication and Authorization 8-32

Configuring the Switch for Secure Shell 8-33

Understanding SSH 8-33

SSH Servers, Integrated Clients, and Supported Versions 8-33 Limitations 8-34

Configuring SSH 8-34

Configuration Guidelines 8-34

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Cryptographic Software Image Guidelines 8-35 Setting Up the Switch to Run SSH 8-35 Configuring the SSH Server 8-36

Displaying the SSH Configuration and Status 8-37

Configuring the Switch for Secure Copy Protocol 8-37

Contents

CHAPTER

9 Configuring IEEE 802.1x Port-Based Authentication 9-1

Understanding IEEE 802.1x Port-Based Authentication 9-1

Device Roles 9-2 Authentication Initiation and Message Exchange 9-3 Ports in Authorized and Unauthorized States 9-4 IEEE 802.1x Accounting 9-5 IEEE 802.1x Accounting Attribute-Value Pairs 9-5 IEEE 802.1x Host Mode 9-6 Using IEEE 802.1x with Port Security 9-7 Using IEEE 802.1x with Voice VLAN Ports 9-8 Using IEEE 802.1x with VLAN Assignment 9-8 Using IEEE 802.1x with Guest VLAN 9-9 Using IEEE 802.1x with Wake-on-LAN 9-10

Unidirectional State 9-10 Bidirectional State 9-10

Configuring IEEE 802.1x Authentication 9-11

Default IEEE 802.1x Configuration 9-11 IEEE 802.1x Configuration Guidelines 9-12 Upgrading from a Previous Software Release 9-13 Enabling IEEE 802.1x Authentication 9-14 Configuring the Switch-to-RADIUS-Server Communication 9-15 Configuring IEEE 802.1x Authentication Using a RADIUS Server 9-16 Enabling Periodic Re-Authentication 9-17 Manually Re-Authenticating a Client Connected to a Port 9-18 Changing the Quiet Period 9-18 Changing the Switch-to-Client Retransmission Time 9-19 Setting the Switch-to-Client Frame-Retransmission Number 9-19 Configuring the Host Mode 9-20 Configuring a Guest VLAN 9-21 Resetting the IEEE 802.1x Configuration to the Default Values 9-22 Configuring IEEE 802.1x Authentication 9-23 Configuring IEEE 802.1x Accounting 9-24

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Displaying IEEE 802.1x Statistics and Status 9-25

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CHAPTER

10 Configuring Interface Characteristics 10-1

Understanding Interface Types 10-1

Access Ports 10-2 Trunk Ports 10-2 Port-Based VLANs 10-3 EtherChannel Port Groups 10-3 Connecting Interfaces 10-4

Using the Interface Command 10-4

Procedures for Configuring Interfaces 10-5 Configuring a Range of Interfaces 10-6 Configuring and Using Interface-Range Macros 10-7

Configuring Ethernet Interfaces 10-9

Default Ethernet Interface Configuration 10-9 Configuring Interface Speed and Duplex Mode 10-10

Configuration Guidelines 10-11 Setting the Interface Speed and Duplex Parameters on a Non-LRE Switch Port 10-12

Setting the Interface Speed and Duplex Parameters on an LRE Switch Port 10-13 Configuring Media Types for Gigabit Ethernet Interfaces on LRE Switches 10-13 Configuring IEEE 802.3z Flow Control on Gigabit Ethernet Ports 10-13 Adding a Description for an Interface 10-15 Configuring Loopback Detection 10-15

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Monitoring and Maintaining the Interfaces 10-16

Monitoring Interface and Controller Status 10-16 Clearing and Resetting Interfaces and Counters 10-17 Shutting Down and Restarting the Interface 10-17

11 Configuring Smartports Macros 11-1

Understanding Smartports Macros 11-1

Configuring Smartports Macros 11-2

Default Smartports Macro Configuration 11-2 Smartports Macro Configuration Guidelines 11-3 Creating Smartports Macros 11-4 Applying Smartports Macros 11-5 Applying Cisco-Default Smartports Macros 11-6

Displaying Smartports Macros 11-8

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Contents

CHAPTER

12 Configuring LRE 12-1

Understanding LRE Features 12-1

Ports on the Catalyst 2950 LRE Switches 12-1 LRE Links and LRE Profiles 12-2

LRE Profiles 12-2 LRE Sequences 12-5

CPE Ethernet Links 12-6 LRE Link Monitor 12-7 LRE Message Logging Process 12-8

Configuring LRE Ports 12-8

Default LRE Configuration 12-9 Environmental Guidelines for LRE Links 12-9 Guidelines for Using LRE Profiles 12-10 CPE Ethernet Link Guidelines 12-11

Guidelines for Configuring Cisco 575 LRE CPEs and 576 LRE 997 CPEs 12-11

Guidelines for Configuring Cisco 585 LRE CPEs 12-12 Assigning a Global Profile to All LRE Ports 12-12 Assigning a Profile to a Specific LRE Port 12-13 Assigning a Global Sequence to All LRE Ports 12-13 Assigning a Sequence to a Specific LRE Port 12-14 Using Rate Selection to Automatically Assign Profiles 12-14

Precedence 12-15

Profile Locking 12-15

Link Qualification and SNR Margins 12-16 Configuring LRE Link Persistence 12-19 Configuring LRE Link Monitor 12-20 Configuring LRE Interleave 12-20 Configuring Upstream Power Back-Off 12-21 Configuring CPE Toggle 12-22 Configuring Syslog Export 12-23

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Upgrading LRE Switch Firmware 12-24

Configuring for an LRE Upgrade 12-24 Performing an LRE Upgrade 12-25

Global Configuration of LRE Upgrades 12-25

Controller Configuration of LRE Upgrades 12-25 LRE Upgrade Details 12-26

LRE Upgrade Example 12-27

Displaying LRE Status 12-27

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CHAPTER

13 Configuring STP 13-1

Understanding Spanning-Tree Features 13-1

STP Overview 13-2 Spanning-Tree Topology and BPDUs 13-2 Bridge ID, Switch Priority, and Extended System ID 13-3 Spanning-Tree Interface States 13-4

Blocking State 13-6 Listening State 13-6 Learning State 13-6 Forwarding State 13-6

Disabled State 13-7 How a Switch or Port Becomes the Root Switch or Root Port 13-7 Spanning Tree and Redundant Connectivity 13-8 Spanning-Tree Address Management 13-8 Accelerated Aging to Retain Connectivity 13-8 Spanning-Tree Modes and Protocols 13-9 Supported Spanning-Tree Instances 13-9 Spanning-Tree Interoperability and Backward Compatibility 13-10 STP and IEEE 802.1Q Trunks 13-10

Configuring Spanning-Tree Features 13-11

Default Spanning-Tree Configuration 13-11 Spanning-Tree Configuration Guidelines 13-12 Changing the Spanning-Tree Mode 13-13 Disabling Spanning Tree 13-14 Configuring the Root Switch 13-14 Configuring a Secondary Root Switch 13-16 Configuring the Port Priority 13-17 Configuring the Path Cost 13-18 Configuring the Switch Priority of a VLAN 13-20 Configuring Spanning-Tree Timers 13-20

Configuring the Hello Time 13-21

Configuring the Forwarding-Delay Time for a VLAN 13-22

Configuring the Maximum-Aging Time for a VLAN 13-22

Configuring Spanning Tree for Use in a Cascaded Stack 13-23

Displaying the Spanning-Tree Status 13-24

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Contents

CHAPTER

14 Configuring MSTP 14-1

Understanding MSTP 14-2

Multiple Spanning-Tree Regions 14-2 IST, CIST, and CST 14-3

Operations Within an MST Region 14-3

Operations Between MST Regions 14-4 Hop Count 14-5 Boundary Ports 14-5 Interoperability with IEEE 802.1D STP 14-5

Understanding RSTP 14-6

Port Roles and the Active Topology 14-6 Rapid Convergence 14-7 Synchronization of Port Roles 14-8 Bridge Protocol Data Unit Format and Processing 14-9

Processing Superior BPDU Information 14-10

Processing Inferior BPDU Information 14-10 Topology Changes 14-10

Configuring MSTP Features 14-11

Default MSTP Configuration 14-12 MSTP Configuration Guidelines 14-12 Specifying the MST Region Configuration and Enabling MSTP 14-13 Configuring the Root Switch 14-14 Configuring a Secondary Root Switch 14-16 Configuring the Port Priority 14-17 Configuring the Path Cost 14-18 Configuring the Switch Priority 14-19 Configuring the Hello Time 14-19 Configuring the Forwarding-Delay Time 14-20 Configuring the Maximum-Aging Time 14-21 Configuring the Maximum-Hop Count 14-21 Specifying the Link Type to Ensure Rapid Transitions 14-22 Restarting the Protocol Migration Process 14-22

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Displaying the MST Configuration and Status 14-23

15 Configuring Optional Spanning-Tree Features 15-1

Understanding Optional Spanning-Tree Features 15-1

Understanding Port Fast 15-2 Understanding BPDU Guard 15-2 Understanding BPDU Filtering 15-3

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Understanding UplinkFast 15-3 Understanding Cross-Stack UplinkFast 15-5

How CSUF Works 15-6 Events that Cause Fast Convergence 15-7 Limitations 15-8

Connecting the Stack Ports 15-8 Understanding BackboneFast 15-9 Understanding EtherChannel Guard 15-12 Understanding Root Guard 15-12 Understanding Loop Guard 15-13

Configuring Optional Spanning-Tree Features 15-13

Default Optional Spanning-Tree Configuration 15-14 Optional Spanning-Tree Configuration Guidelines 15-14 Enabling Port Fast 15-14 Enabling BPDU Guard 15-15 Enabling BPDU Filtering 15-16 Enabling UplinkFast for Use with Redundant Links 15-17 Enabling Cross-Stack UplinkFast 15-18 Enabling BackboneFast 15-19 Enabling EtherChannel Guard 15-20 Enabling Root Guard 15-21 Enabling Loop Guard 15-21

CHAPTER

Displaying the Spanning-Tree Status 15-22

16 Configuring VLANs 16-1

Understanding VLANs 16-1

Supported VLANs 16-2 VLAN Port Membership Modes 16-3

Configuring Normal-Range VLANs 16-4

Token Ring VLANs 16-5 Normal-Range VLAN Configuration Guidelines 16-5 VLAN Configuration Mode Options 16-6

VLAN Configuration in config-vlan Mode 16-6

VLAN Configuration in VLAN Configuration Mode 16-6 Saving VLAN Configuration 16-7 Default Ethernet VLAN Configuration 16-7 Creating or Modifying an Ethernet VLAN 16-8 Deleting a VLAN 16-10 Assigning Static-Access Ports to a VLAN 16-11

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Configuring Extended-Range VLANs 16-11

Default VLAN Configuration 16-12 Extended-Range VLAN Configuration Guidelines 16-12 Creating an Extended-Range VLAN 16-13

Displaying VLANs 16-14

Configuring VLAN Trunks 16-14

Trunking Overview 16-14

IEEE 802.1Q Configuration Considerations 16-16 Default Layer 2 Ethernet Interface VLAN Configuration 16-17 Configuring an Ethernet Interface as a Trunk Port 16-17

Interaction with Other Features 16-17

Configuring a Trunk Port 16-18

Defining the Allowed VLANs on a Trunk 16-19

Changing the Pruning-Eligible List 16-20

Configuring the Native VLAN for Untagged Traffic 16-20 Load Sharing Using STP 16-21

Load Sharing Using STP Port Priorities 16-21

Load Sharing Using STP Path Cost 16-23

Contents

CHAPTER

Configuring VMPS 16-24

Understanding VMPS 16-25

Dynamic Port VLAN Membership 16-25

VMPS Database Configuration File 16-26 Default VMPS Client Configuration 16-26 VMPS Configuration Guidelines 16-26 Configuring the VMPS Client 16-27

Entering the IP Address of the VMPS 16-27

Configuring Dynamic Access Ports on VMPS Clients 16-28

Reconfirming VLAN Memberships 16-28

Changing the Reconfirmation Interval 16-29

Changing the Retry Count 16-29 Monitoring the VMPS 16-30 Troubleshooting Dynamic Port VLAN Membership 16-30 VMPS Configuration Example 16-31

17 Configuring VTP 17-1

Understanding VTP 17-1

The VTP Domain 17-2 VTP Modes 17-3 VTP Advertisements 17-3

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VTP Version 2 17-4 VTP Pruning 17-4

Configuring VTP 17-6

Default VTP Configuration 17-6 VTP Configuration Options 17-7

VTP Configuration in Global Configuration Mode 17-7 VTP Configuration in VLAN Configuration Mode 17-7

VTP Configuration Guidelines 17-8

Domain Names 17-8 Passwords 17-8 Upgrading from Previous Software Releases 17-8 VTP Version 17-9

Configuration Requirements 17-9 Configuring a VTP Server 17-9 Configuring a VTP Client 17-11 Disabling VTP (VTP Transparent Mode) 17-12 Enabling VTP Version 2 17-13 Enabling VTP Pruning 17-14 Adding a VTP Client Switch to a VTP Domain 17-15

CHAPTER

Monitoring VTP 17-16

18 Configuring Voice VLAN 18-1

Understanding Voice VLAN 18-1

Configuring Voice VLAN 18-2

Default Voice VLAN Configuration 18-2 Voice VLAN Configuration Guidelines 18-3 Configuring a Port to Connect to a Cisco 7960 IP Phone 18-3

Configuring Ports to Carry Voice Traffic in IEEE 802.1Q Frames 18-4

Configuring Ports to Carry Voice Traffic in IEEE 802.1p Priority-Tagged Frames 18-4

Overriding the CoS Priority of Incoming Data Frames 18-5

Configuring the IP Phone to Trust the CoS Priority of Incoming Data Frames 18-6

Displaying Voice VLAN 18-6

19 Configuring DHCP Features 19-1

Understanding DHCP Features 19-1

DHCP Server 19-2 DHCP Relay Agent 19-2 DHCP Snooping 19-2 Option-82 Data Insertion 19-3

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Configuring DHCP Features 19-5

Default DHCP Configuration 19-6 DHCP Snooping Configuration Guidelines 19-6 Configuring the DHCP Server 19-7 Enabling DHCP Snooping and Option 82 19-7

Displaying DHCP Information 19-8

Contents

CHAPTER

20 Configuring IGMP Snooping and MVR 20-1

Understanding IGMP Snooping 20-2

IGMP Versions 20-2 Joining a Multicast Group 20-3 Leaving a Multicast Group 20-5 Immediate-Leave Processing 20-5 IGMP Configurable-Leave Timer 20-5

IGMP Leave Timer Guidelines 20-6 IGMP Report Suppression 20-6 IGMP Snooping Querier Configuration Guidelines and Restrictions 20-6 Source-Only Networks 20-7

Configuring IGMP Snooping 20-7

Default IGMP Snooping Configuration 20-8 Enabling or Disabling IGMP Snooping 20-8 Setting the Snooping Method 20-9 Configuring a Multicast Router Port 20-10 Configuring a Host Statically to Join a Group 20-10 Enabling IGMP Immediate-Leave Processing 20-11 Configuring the IGMP Leave Timer 20-12 Disabling IGMP Report Suppression 20-12 Disabling IP Multicast-Source-Only Learning 20-13 Configuring the Aging Time 20-14 Configuring the IGMP Snooping Querier 20-14

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Displaying IGMP Snooping Information 20-15

Understanding Multicast VLAN Registration 20-16

Using MVR in a Multicast Television Application 20-17

Configuring MVR 20-19

Default MVR Configuration 20-19 MVR Configuration Guidelines and Limitations 20-19 Configuring MVR Global Parameters 20-20 Configuring MVR Interfaces 20-21

Displaying MVR Information 20-22

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Configuring IGMP Filtering and Throttling 20-23

Default IGMP Filtering and Throttling Configuration 20-23 Configuring IGMP Profiles 20-24 Applying IGMP Profiles 20-25 Setting the Maximum Number of IGMP Groups 20-26 Configuring the IGMP Throttling Action 20-26

Displaying IGMP Filtering and Throttling Configuration 20-28

CHAPTER

21 Configuring Port-Based Traffic Control 21-1

Configuring Storm Control 21-1

Understanding Storm Control 21-1 Default Storm Control Configuration 21-2 Configuring Storm Control and Threshold Levels 21-2

Configuring Protected Ports 21-4

Configuring Port Blocking 21-5

Blocking Flooded Traffic on an Interface 21-5 Resuming Normal Forwarding on a Port 21-6

Configuring Port Security 21-6

Understanding Port Security 21-6

Secure MAC Addresses 21-6

Security Violations 21-7 Default Port Security Configuration 21-8 Port Security Configuration Guidelines 21-8 Enabling and Configuring Port Security 21-9 Enabling and Configuring Port Security Aging 21-11

Displaying Port-Based Traffic Control Settings 21-13

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22 Configuring UDLD 22-1

Understanding UDLD 22-1

Modes of Operation 22-1 Methods to Detect Unidirectional Links 22-2

Configuring UDLD 22-4

Default UDLD Configuration 22-4 Configuration Guidelines 22-4 Enabling UDLD Globally 22-5 Enabling UDLD on an Interface 22-6 Resetting an Interface Shut Down by UDLD 22-6

Displaying UDLD Status 22-7

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CHAPTER

23 Configuring CDP 23-1

Understanding CDP 23-1

Configuring CDP 23-2

Default CDP Configuration 23-2 Configuring the CDP Characteristics 23-2 Disabling and Enabling CDP 23-3 Disabling and Enabling CDP on an Interface 23-4

Monitoring and Maintaining CDP 23-5

24 Configuring SPAN and RSPAN 24-1

Understanding SPAN and RSPAN 24-1

SPAN and RSPAN Concepts and Terminology 24-3

SPAN Session 24-3 Traffic Types 24-3 Source Port 24-4 Destination Port 24-4 Reflector Port 24-5

SPAN Traffic 24-5 SPAN and RSPAN Interaction with Other Features 24-6 SPAN and RSPAN Session Limits 24-7 Default SPAN and RSPAN Configuration 24-7

CHAPTER

Configuring SPAN 24-7

SPAN Configuration Guidelines 24-7 Creating a SPAN Session and Specifying Ports to Monitor 24-8 Creating a SPAN Session and Enabling Ingress Traffic 24-9 Removing Ports from a SPAN Session 24-11

Configuring RSPAN 24-12

RSPAN Configuration Guidelines 24-12 Configuring a VLAN as an RSPAN VLAN 24-13 Creating an RSPAN Source Session 24-14 Creating an RSPAN Destination Session 24-15 Removing Ports from an RSPAN Session 24-16

Displaying SPAN and RSPAN Status 24-17

25 Configuring RMON 25-1

Understanding RMON 25-1

Configuring RMON 25-2

Default RMON Configuration 25-3

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Configuring RMON Alarms and Events 25-3 Configuring RMON Collection on an Interface 25-5

Displaying RMON Status 25-6

CHAPTER

26 Configuring System Message Logging 26-1

Understanding System Message Logging 26-1

Configuring System Message Logging 26-2

System Log Message Format 26-2 Default System Message Logging Configuration 26-3 Disabling and Enabling Message Logging 26-4 Setting the Message Display Destination Device 26-4 Synchronizing Log Messages 26-6 Enabling and Disabling Timestamps on Log Messages 26-7 Enabling and Disabling Sequence Numbers in Log Messages 26-8 Defining the Message Severity Level 26-8 Limiting Syslog Messages Sent to the History Table and to SNMP 26-9 Configuring UNIX Syslog Servers 26-10

Logging Messages to a UNIX Syslog Daemon 26-11 Configuring the UNIX System Logging Facility 26-11

Displaying the Logging Configuration 26-12

27 Configuring SNMP 27-1

Understanding SNMP 27-1

SNMP Versions 27-2 SNMP Manager Functions 27-3 SNMP Agent Functions 27-4 SNMP Community Strings 27-4 Using SNMP to Access MIB Variables 27-4 SNMP Notifications 27-5

Configuring SNMP 27-6

Default SNMP Configuration 27-6 SNMP Configuration Guidelines 27-6 Disabling the SNMP Agent 27-7 Configuring Community Strings 27-8 Configuring SNMP Groups and Users 27-9 Configuring SNMP Notifications 27-11 Setting the Agent Contact and Location Information 27-14 Limiting TFTP Servers Used Through SNMP 27-14 SNMP Examples 27-15

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Displaying SNMP Status 27-16

Contents

CHAPTER

28 Configuring Network Security with ACLs 28-1

Understanding ACLs 28-2

Handling Fragmented and Unfragmented Traffic 28-3 Understanding Access Control Parameters 28-4 Guidelines for Applying ACLs to Physical Interfaces 28-6

Configuring ACLs 28-6

Unsupported Features 28-7 Creating Standard and Extended IP ACLs 28-7

ACL Numbers 28-8

Creating a Numbered Standard ACL 28-8

Creating a Numbered Extended ACL 28-10

Creating Named Standard and Extended ACLs 28-13

Applying Time Ranges to ACLs 28-14

Including Comments About Entries in ACLs 28-16 Creating Named MAC Extended ACLs 28-17 Creating MAC Access Groups 28-18

Applying ACLs to Terminal Lines or Physical Interfaces 28-18

Applying ACLs to a Terminal Line 28-19 Applying ACLs to a Physical Interface 28-20

CHAPTER

Displaying ACL Information 28-20

Displaying ACLs 28-20 Displaying Access Groups 28-22

Examples for Compiling ACLs 28-23

Numbered ACL Examples 28-24 Extended ACL Examples 28-24 Named ACL Example 28-24 Commented IP ACL Entry Examples 28-25

29 Configuring QoS 29-1

Understanding QoS 29-2

Basic QoS Model 29-4 Classification 29-5

Classification Based on QoS ACLs 29-5

Classification Based on Class Maps and Policy Maps 29-6 Policing and Marking 29-7 Mapping Tables 29-8 Queueing and Scheduling 29-8

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Contents

How Class of Service Works 29-8 Port Priority 29-8 Port Scheduling 29-9 Egress CoS Queues 29-9

Configuring Auto-QoS 29-10

Generated Auto-QoS Configuration 29-10 Effects of Auto-QoS on the Configuration 29-12 Configuration Guidelines 29-13 Upgrading from a Previous Software Release 29-13 Enabling Auto-QoS for VoIP 29-14

Displaying Auto-QoS Information 29-15

Auto-QoS Configuration Example 29-15

Configuring Standard QoS 29-18

Default Standard QoS Configuration 29-18 Configuration Guidelines 29-19 Configuring Classification Using Port Trust States 29-20

Configuring the Trust State on Ports within the QoS Domain 29-20 Configuring the CoS Value for an Interface 29-22 Configuring Trusted Boundary 29-23 Enabling Pass-Through Mode 29-25

Configuring a QoS Policy 29-26

Classifying Traffic by Using ACLs 29-27 Classifying Traffic by Using Class Maps 29-30 Classifying, Policing, and Marking Traffic by Using Policy Maps 29-31

Configuring CoS Maps 29-34

Configuring the CoS-to-DSCP Map 29-35 Configuring the DSCP-to-CoS Map 29-36

Configuring the Egress Queues 29-37

Configuring CoS Priority Queues 29-37 Configuring WRR Priority 29-38 Enabling the Expedite Queue and Configuring WRR Priority 29-38

CHAPTER

xxii

Displaying Standard QoS Information 29-39

Standard QoS Configuration Examples 29-39

QoS Configuration for the Existing Wiring Closet 29-40 QoS Configuration for the Intelligent Wiring Closet 29-41

30 Configuring EtherChannels 30-1

Understanding EtherChannels 30-1

Understanding Port-Channel Interfaces 30-2

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Understanding the Port Aggregation Protocol and Link Aggregation Protocol 30-3

PAgP and LACP Modes 30-4

Physical Learners and Aggregate-Port Learners 30-5

PAgP and LACP Interaction with Other Features 30-6 Understanding Load Balancing and Forwarding Methods 30-6

Configuring EtherChannels 30-7

Default EtherChannel Configuration 30-8 EtherChannel Configuration Guidelines 30-8 Configuring Layer 2 EtherChannels 30-9 Configuring EtherChannel Load Balancing 30-11 Configuring the PAgP Learn Method and Priority 30-12 Configuring the LACP Port Priority 30-12 Configuring Hot Standby Ports 30-13 Configuring the LACP System Priority 30-13

Displaying EtherChannel, PAgP, and LACP Status 30-14

Contents

CHAPTER

31 Troubleshooting 31-1

Using Recovery Procedures 31-1

Recovering from a Software Failure 31-2 Recovering from Lost or Forgotten Passwords on Non-LRE Catalyst 2950 Switches 31-2 Recovering from Lost or Forgotten Passwords on Catalyst 2950 LRE Switches 31-4

Password Recovery with Password Recovery Enabled 31-5

Procedure with Password Recovery Disabled 31-6 Recovering from Lost or Forgotten Passwords on Catalyst 2955 Switches 31-8 Recovering from a Command Switch Failure 31-10

Replacing a Failed Command Switch with a Cluster Member 31-10

Replacing a Failed Command Switch with Another Switch 31-12 Recovering from Lost Member Connectivity 31-13

Preventing Autonegotiation Mismatches 31-14

GBIC and SFP Module Security and Identification 31-14

Diagnosing Connectivity Problems 31-14

Using Ping 31-15

Understanding Ping 31-15

Executing Ping 31-15 Using Layer 2 Traceroute 31-16

Understanding Layer 2 Traceroute 31-16

Usage Guidelines 31-16

Displaying the Physical Path 31-17

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Diagnosing LRE Connection Problems 31-18

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Contents

Using Debug Commands 31-19

Enabling Debugging on a Specific Feature 31-20 Enabling All-System Diagnostics 31-20 Redirecting Debug and Error Message Output 31-20 Using the debug auto qos Command 31-21

Using the show controllers Commands 31-22

Using the crashinfo File 31-22

APPENDIX

A Supported MIBs A-1

MIB List A-1

Using FTP to Access the MIB Files A-3

B Working with the Cisco IOS File System, Configuration Files, and Software Images B-1

Working with the Flash File System B-1

Displaying Available File Systems B-2 Setting the Default File System B-3 Displaying Information about Files on a File System B-3 Changing Directories and Displaying the Working Directory B-4 Creating and Removing Directories B-4 Copying Files B-5 Deleting Files B-5 Creating, Displaying, and Extracting tar Files B-6

Creating a tar File B-6 Displaying the Contents of a tar File B-7 Extracting a tar File B-7

Displaying the Contents of a File B-8

xxiv

Working with Configuration Files B-8

Guidelines for Creating and Using Configuration Files B-9 Configuration File Types and Location B-10 Creating a Configuration File By Using a Text Editor B-10 Copying Configuration Files By Using TFTP B-10

Preparing to Download or Upload a Configuration File By Using TFTP B-10 Downloading the Configuration File By Using TFTP B-11 Uploading the Configuration File By Using TFTP B-12

Copying Configuration Files By Using FTP B-12

Preparing to Download or Upload a Configuration File By Using FTP B-13 Downloading a Configuration File By Using FTP B-13 Uploading a Configuration File By Using FTP B-14

Copying Configuration Files By Using RCP B-15

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Preparing to Download or Upload a Configuration File By Using RCP B-16

Downloading a Configuration File By Using RCP B-17

Uploading a Configuration File By Using RCP B-18 Clearing Configuration Information B-19

Clearing the Startup Configuration File B-19

Deleting a Stored Configuration File B-19

Working with Software Images B-19

Image Location on the Switch B-20 tar File Format of Images on a Server or Cisco.com B-20 Copying Image Files By Using TFTP B-21

Preparing to Download or Upload an Image File By Using TFTP B-22

Downloading an Image File By Using TFTP B-22

Uploading an Image File By Using TFTP B-24 Copying Image Files By Using FTP B-24

Preparing to Download or Upload an Image File By Using FTP B-25

Downloading an Image File By Using FTP B-26

Uploading an Image File By Using FTP B-27 Copying Image Files By Using RCP B-28

Preparing to Download or Upload an Image File By Using RCP B-29

Downloading an Image File By Using RCP B-30

Uploading an Image File By Using RCP B-32

Contents

NDEX

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Contents

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Audience

Purpose

Preface

This guide is for the networking professional managing the Catalyst 2950 and 2955 switches, hereafter referred to as the switches. Before using this guide, you should have experience working with the Cisco IOS and be familiar with the concepts and terminology of Ethernet and local area networking.

This guide provides the information you need to configure software features on your switch. The Catalyst 2950 switch is supported by either the standard software image (SI) or the enhanced software image (EI). The Catalyst 2955 and Catalyst 2950 Long-Reach Ethernet (LRE) switches are supported only by the EI.

The EI provides a richer set of features, including access control lists (ACLs), enhanced quality of service (QoS) features, extended-range VLANs, Remote Switched Port Analyzer (RSPAN), and unicast MAC address filtering. The cryptographic EI provides support for the Secure Shell Protocol (SSP). For a list of switches that support the SI and the EI, see Tabl e 1-1 in Chapter 1, “Overview.”

The Catalyst 2955 switch also supports an additional set of features that are described in Chapter 3,

“Configuring Catalyst 2955 Switch Alarms.” The switch has facilities to process alarms related to the

temperature, power supply conditions, and status of the Ethernet ports.

Use this guide with other documents for information about these topics:

• Requirements—This guide assumes that you have met the hardware and software requirements and

cluster compatibility requirements described in the release notes.

• Start-up information—This guide assumes that you have assigned switch IP information and

passwords by using the browser setup program described in the switch hardware installation guide.

• Embedded device manager and Network Assistant graphical user interfaces (GUIs)—This guide

does not provide detailed information on the GUIs. However, the concepts in this guide are applicable to the GUI user. For information about the device manager, see the switch online help. For information about Network Assistant, see the Getting Started with Cisco Network Assistant, available on Cisco.com.

• Cluster configuration—For information about planning for, creating, and maintaining switch

clusters, see the Getting Started with Cisco Network Assistant, available on Cisco.com. For information about the clustering-related command-line interface (CLI) commands, see the command reference for this release.

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Conventions

This guide provides procedures for using the commands that have been created or changed for use with the switch. It does not provide detailed information about these commands. For detailed information about these commands, see the command reference for this release.

This guide does not repeat the concepts and CLI procedures provided in the standard Cisco IOS Release 12.1 documentation. For information about the standard Cisco IOS Release 12.1 commands, see the Cisco IOS documentation set available from the Cisco.com home page at Service and Support > Technical Documents. On the Cisco Product Documentation home page, select Release 12.1 from the Cisco IOS Software drop-down list.

This guide does not describe system messages you might encounter or how to install your switch. For this information, see the system message guide for this release and to the hardware installation guide.

For documentation updates, see the release notes for this release.

Conventions

Preface

• CLI command information—This guide provides an overview for using the CLI. For complete

syntax and usage information about the commands that have been specifically created or changed for the switches, see the command reference for this release.

This publication uses these conventions to convey instructions and information:

Command descriptions use these conventions:

• Commands and keywords are in boldface text.

• Arguments for which you supply values are in italic.

• Square brackets ([ ]) mean optional elements.

• Braces ({ }) group required choices, and vertical bars ( | ) separate the alternative elements.

• Braces and vertical bars within square brackets ([{ | }]) mean a required choice within an optional

element.

Interactive examples use these conventions:

• Terminal sessions and system displays are in screen font.

• Information you enter is in boldface screen font.

• Nonprinting characters, such as passwords or tabs, are in angle brackets (< >).

Notes, cautions, and timesavers use these conventions and symbols:

Note Means reader take note. Notes contain helpful suggestions or references to materials not contained in

this manual.

Caution Means reader be careful. In this situation, you might do something that could result equipment damage

or loss of data.

xxviii

Timesaver Means the following will help you solve a problem. The tips information might not be troubleshooting

or even an action, but could be useful information.

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Preface

Related Publications

These documents provide complete information about the switch and are available from this Cisco.com site:

http://www.cisco.com/univercd/cc/td/doc/product/lan/cat2950/index.htm

You can order printed copies of documents with a DOC-xxxxxx= number from the Cisco.com sites and from the telephone numbers listed in the “Obtaining Documentation” section on page Boilerplate 1.

• Release Notes for the Catalyst 2950 and Catalyst 2955 Switches (not orderable but available on

Cisco.com)

Note Switch requirements and procedures for initial configurations and software upgrades tend to change and

therefore appear only in the release notes. Before installing, configuring, or upgrading the switch, see the release notes on Cisco.com for the latest information.

For information about the switch, see these documents:

• Catalyst 2950 and Catalyst 2955 Switch Software Configuration Guide (order number

DOC-7811380=)

Related Publications

• Catalyst 2950 and Catalyst 2955 Switch Command Reference (order number DOC-7811381=)

• Catalyst 2950 and Catalyst 2955 Switch System Message Guide (order number DOC-7814233=)

• Device manager online help (available on the switch)

• Catalyst 2950 Switch Hardware Installation Guide (not orderable but available on Cisco.com)

• Catalyst 2950 Switch Getting Started Guide (order number DOC-1786521=)

• Regulatory Compliance and Safety Information for the Catalyst 2950 Switch (order number

DOC-7816625=)

• Catalyst 2955 Switch Hardware Installation Guide (order number DOC-7814944=)

For information about related products, see these documents:

• Getting Started with Cisco Network Assistant (not orderable but available on Cisco.com)

• Release Notes for Cisco Network Assistant (not orderable but available on Cisco.com)

• Catalyst GigaStack Gigabit Interface Converter Hardware Installation Guide

(order number DOC-786460=)

• CWDM Passive Optical System Installation Note (not orderable but is available on Cisco.com)

• 1000BASE-T Gigabit Interface Converter Installation Notes (not orderable but is available on

Cisco.com)

• Cisco Small Form-Factor Pluggable Modules Installation Notes (order number DOC-7815160=)

• Cisco CWDM GBIC and CWDM SFP Installation Note (not orderable but available on Cisco.com)

Obtaining Documentation

Cisco documentation and additional literature are available on Cisco.com. Cisco also provides several ways to obtain technical assistance and other technical resources. These sections explain how to obtain technical information from Cisco Systems.

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Obtaining Documentation

Cisco.com

You can access the most current Cisco documentation at this URL:

http://www.cisco.com/techsupport

You can access the Cisco website at this URL:

http://www.cisco.com

You can access international Cisco websites at this URL:

http://www.cisco.com/public/countries_languages.shtml

Product Documentation DVD

Cisco documentation and additional literature are available in the Product Documentation DVD package, which may have shipped with your product. The Product Documentation DVD is updated regularly and may be more current than printed documentation.

The Product Documentation DVD is a comprehensive library of technical product documentation on portable media. The DVD enables you to access multiple versions of hardware and software installation, configuration, and command guides for Cisco products and to view technical documentation in HTML. With the DVD, you have access to the same documentation that is found on the Cisco website without being connected to the Internet. Certain products also have .pdf versions of the documentation available.

Preface

The Product Documentation DVD is available as a single unit or as a subscription. Registered Cisco.com users (Cisco direct customers) can order a Product Documentation DVD (product number DOC-DOCDVD=) from the Ordering tool or Cisco Marketplace.

Cisco Ordering tool:

http://www.cisco.com/en/US/partner/ordering/

Cisco Marketplace:

http://www.cisco.com/go/marketplace/

Ordering Documentation

Beginning June 30, 2005, registered Cisco.com users may order Cisco documentation at the Product Documentation Store in the Cisco Marketplace at this URL:

http://www.cisco.com/go/marketplace/

Cisco will continue to support documentation orders using the Ordering tool:

• Registered Cisco.com users (Cisco direct customers) can order documentation from the

Ordering tool:

http://www.cisco.com/en/US/partner/ordering/

• Instructions for ordering documentation using the Ordering tool are at this URL:

http://www.cisco.com/univercd/cc/td/doc/es_inpck/pdi.htm

• Nonregistered Cisco.com users can order documentation through a local account representative by

calling Cisco Systems Corporate Headquarters (California, USA) at 408 526-7208 or, elsewhere in North America, by calling 1 800 553-NETS (6387).

xxx

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Preface

Documentation Feedback

You can rate and provide feedback about Cisco technical documents by completing the online feedback form that appears with the technical documents on Cisco.com.

You can send comments about Cisco documentation to bug-doc@cisco.com.

You can submit comments by using the response card (if present) behind the front cover of your document or by writing to the following address:

Cisco Systems Attn: Customer Document Ordering 170 West Tasman Drive San Jose, CA 95134-9883

We appreciate your comments.

Cisco Product Security Overview

Cisco provides a free online Security Vulnerability Policy portal at this URL:

Documentation Feedback

http://www.cisco.com/en/US/products/products_security_vulnerability_policy.html

From this site, you can perform these tasks:

• Report security vulnerabilities in Cisco products.

• Obtain assistance with security incidents that involve Cisco products.

• Register to receive security information from Cisco.

A current list of security advisories and notices for Cisco products is available at this URL:

http://www.cisco.com/go/psirt

If you prefer to see advisories and notices as they are updated in real time, you can access a Product Security Incident Response Team Really Simple Syndication (PSIRT RSS) feed from this URL:

http://www.cisco.com/en/US/products/products_psirt_rss_feed.html

Reporting Security Problems in Cisco Products

Cisco is committed to delivering secure products. We test our products internally before we release them, and we strive to correct all vulnerabilities quickly. If you think that you might have identified a vulnerability in a Cisco product, contact PSIRT:

• Emergencies— security-alert@cisco.com

An emergency is either a condition in which a system is under active attack or a condition for which a severe and urgent security vulnerability should be reported. All other conditions are considered nonemergencies.

• Nonemergencies— psirt@cisco.com

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In an emergency, you can also reach PSIRT by telephone:

• 1 877 228-7302

• 1 408 525-6532

Catalyst 2950 and Catalyst 2955 Switch Software Configuration Guide

xxxi

Obtaining Technical Assistance

Tip We encourage you to use Pretty Good Privacy (PGP) or a compatible product to encrypt any sensitive

information that you send to Cisco. PSIRT can work from encrypted information that is compatible with PGP versions 2.x through 8.x.

Never use a revoked or an expired encryption key. The correct public key to use in your correspondence with PSIRT is the one linked in the Contact Summary section of the Security Vulnerability Policy page at this URL:

http://www.cisco.com/en/US/products/products_security_vulnerability_policy.htm

The link on this page has the current PGP key ID in use.

Obtaining Technical Assistance

Cisco Technical Support provides 24-hour-a-day award-winning technical assistance. The Cisco Technical Support & Documentation website on Cisco.com features extensive online support resources. In addition, if you have a valid Cisco service contract, Cisco Technical Assistance Center (TAC) engineers provide telephone support. If you do not have a valid Cisco service contract, contact your reseller.

Preface

Cisco Technical Support & Documentation Website

The Cisco Technical Support & Documentation website provides online documents and tools for troubleshooting and resolving technical issues with Cisco products and technologies. The website is available 24 hours a day, at this URL:

http://www.cisco.com/techsupport

Access to all tools on the Cisco Technical Support & Documentation website requires a Cisco.com user ID and password. If you have a valid service contract but do not have a user ID or password, you can register at this URL:

http://tools.cisco.com/RPF/register/register.do

Note Use the Cisco Product Identification (CPI) tool to locate your product serial number before submitting

a web or phone request for service. You can access the CPI tool from the Cisco Technical Support & Documentation website by clicking the Tools & Resources link under Documentation & Tools. Choose

Cisco Product Identification Tool from the Alphabetical Index drop-down list, or click the Cisco Product Identification Tool link under Alerts & RMAs. The CPI tool offers three search options: by

product ID or model name; by tree view; or for certain products, by copying and pasting show command output. Search results show an illustration of your product with the serial number label location highlighted. Locate the serial number label on your product and record the information before placing a service call.

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Preface

Submitting a Service Request

Using the online TAC Service Request Tool is the fastest way to open S3 and S4 service requests. (S3 and S4 service requests are those in which your network is minimally impaired or for which you require product information.) After you describe your situation, the TAC Service Request Tool provides recommended solutions. If your issue is not resolved using the recommended resources, your service request is assigned to a Cisco engineer. The TAC Service Request Tool is located at this URL:

http://www.cisco.com/techsupport/servicerequest

For S1 or S2 service requests or if you do not have Internet access, contact the Cisco TAC by telephone. (S1 or S2 service requests are those in which your production network is down or severely degraded.) Cisco engineers are assigned immediately to S1 and S2 service requests to help keep your business operations running smoothly.

To open a service request by telephone, use one of the following numbers:

Asia-Pacific: +61 2 8446 7411 (Australia: 1 800 805 227) EMEA: +32 2 704 55 55 USA: 1 800 553-2447

For a complete list of Cisco TAC contacts, go to this URL:

http://www.cisco.com/techsupport/contacts

Obtaining Additional Publications and Information

Definitions of Service Request Severity

To ensure that all service requests are reported in a standard format, Cisco has established severity definitions.

Severity 1 (S1)—Your network is “down,” or there is a critical impact to your business operations. You and Cisco will commit all necessary resources around the clock to resolve the situation.

Severity 2 (S2)—Operation of an existing network is severely degraded, or significant aspects of your business operation are negatively affected by inadequate performance of Cisco products. You and Cisco will commit full-time resources during normal business hours to resolve the situation.

Severity 3 (S3)—Operational performance of your network is impaired, but most business operations remain functional. You and Cisco will commit resources during normal business hours to restore service to satisfactory levels.

Severity 4 (S4)—You require information or assistance with Cisco product capabilities, installation, or configuration. There is little or no effect on your business operations.

Obtaining Additional Publications and Information

Information about Cisco products, technologies, and network solutions is available from various online and printed sources.

• Cisco Marketplace provides a variety of Cisco books, reference guides, documentation, and logo

merchandise. Visit Cisco Marketplace, the company store, at this URL:

78-11380-12

http://www.cisco.com/go/marketplace/

Catalyst 2950 and Catalyst 2955 Switch Software Configuration Guide

xxxiii

Obtaining Additional Publications and Information

• Cisco Press publishes a wide range of general networking, training and certification titles. Both new

and experienced users will benefit from these publications. For current Cisco Press titles and other information, go to Cisco Press at this URL:

http://www.ciscopress.com

• Packet magazine is the Cisco Systems technical user magazine for maximizing Internet and

networking investments. Each quarter, Packet delivers coverage of the latest industry trends, technology breakthroughs, and Cisco products and solutions, as well as network deployment and troubleshooting tips, configuration examples, customer case studies, certification and training information, and links to scores of in-depth online resources. You can access Packet magazine at this URL:

http://www.cisco.com/packet

• iQ Magazine is the quarterly publication from Cisco Systems designed to help growing companies

learn how they can use technology to increase revenue, streamline their business, and expand services. The publication identifies the challenges facing these companies and the technologies to help solve them, using real-world case studies and business strategies to help readers make sound technology investment decisions. You can access iQ Magazine at this URL:

http://www.cisco.com/go/iqmagazine

Preface

or view the digital edition at this URL:

http://ciscoiq.texterity.com/ciscoiq/sample/

• Internet Protocol Journal is a quarterly journal published by Cisco Systems for engineering

professionals involved in designing, developing, and operating public and private internets and intranets. You can access the Internet Protocol Journal at this URL:

http://www.cisco.com/ipj

• Networking products offered by Cisco Systems, as well as customer support services, can be

obtained at this URL:

http://www.cisco.com/en/US/products/index.html

• Networking Professionals Connection is an interactive website for networking professionals to share

questions, suggestions, and information about networking products and technologies with Cisco experts and other networking professionals. Join a discussion at this URL:

http://www.cisco.com/discuss/networking

• World-class networking training is available from Cisco. You can view current offerings at

this URL:

http://www.cisco.com/en/US/learning/index.html

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Note In this document, IP refers to IP version 4 (IPv4). Layer 3 IP version 6 (IPv6) packets are treated as

Features

CHAPTER

Overview

This chapter provides these topics about the Catalyst 2950 and Catalyst 2955 switch software:

• Features, page 1-1

• Management Options, page 1-9

• Network Configuration Examples, page 1-11

• Where to Go Next, page 1-24

non-IP packets.

The switch software supports the switches listed in Table 1-1 and in the release notes.

Table 1-1 Switches Supported

Switch Software Image

Catalyst 2950-12 SI

Catalyst 2950-24 SI

Catalyst 2950C-24 EI

Catalyst 2950G-12-EI EI

Catalyst 2950G-24-EI EI

Catalyst 2950G-24-EI-DC EI

Catalyst 2950G-48-EI EI

Catalyst 2950ST-8 LRE EI

Catalyst 2950ST-24 LRE EI

Catalyst 2950ST-24 LRE 997 EI

Catalyst 2950SX-24 SI

Catalyst 2950SX-48-SI SI

Catalyst 2950T-24 EI

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Features

Chapter 1 Overview

Table 1-1 Switches Supported (continued)

Switch Software Image

Catalyst 2950T-48-SI SI

Catalyst 2955C-12 EI

Catalyst 2955S-12 EI

Catalyst 2955T-12 EI

1. SI = standard software image

2. EI = enhanced software image

Certain Cisco Long-Reach Ethernet (LRE) customer premises equipment (CPE) devices are not supported by certain Catalyst 2950 LRE switches. In Ta ble 1-2, Yes means that the CPE is supported by the switch; No means that the CPE is not supported by the switch.

Table 1-2 LRE Switch and CPE Compatibility Matrix

Catalyst 2950ST-8 LRE

LRE Devices

Cisco 575 LRE

switch

Yes Yes No

CPE

Cisco 576 LRE 997

No No Yes

CPE

Cisco 585 LRE

Yes Yes No

CPE

This section describes the features supported in this release:

Note Some features require that you have the EI installed on your switch. For a list of the switches that support

the EI, see Tab le 1-1, or see the release notes for this release.

Ease of Use and Ease of Deployment

• Express Setup for quickly configuring a switch for the first time with basic IP information, contact

information, switch and Telnet passwords, and Simple Network Management Protocol (SNMP) information through a browser-based program.

• User-defined Smartports macros for creating custom switch configurations for simplified

deployment across the network.

Catalyst 2950ST-24 LRE switch

Catalyst 2950ST-24 LRE 997 switch

1-2

• Embedded device manager GUI for configuring and monitoring a single switch through a web

browser. For information about launching the device manager, see the getting started guide. For more information about the device manager, see the switch online help.

• Network Assistant application for

–

Simplifying and minimizing switch and switch cluster management from anywhere in your intranet.

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Chapter 1 Overview

Features

–

Accomplishing multiple configuration tasks from a single window without needing to remember command-line interface (CLI) commands to accomplish specific tasks.

–

Interactive guide mode that guides you in configuring complex features such as VLANs, ACLs, and quality of service (QoS).

–

Automated configuration wizards that prompt you to provide only the minimum required information to configure complex features such as QoS priorities for video traffic, priority levels for data applications, and security.

–

Downloading an image to a switch by using TFTP.

–

Applying actions to multiple ports and multiple switches at the same time, such as VLAN and QoS settings, inventory and statistic reports, link- and switch-level monitoring and troubleshooting, and multiple switch software upgrades.

–

Viewing a topology of interconnected devices to identify existing switch clusters and eligible switches that can join a cluster and to identify link information between switches.

• Real-time status monitoring of a switch or multiple switches from the LEDs on the front-panel

images from the device manager and from Network Assistant.

• Switch clustering technology for

–

Unified configuration, monitoring, authentication, and software upgrade of multiple switches (see the release notes for a list of eligible cluster members).

–

Automatic discovery of candidate switches and creation of clusters of up to 16 switches that can be managed through a single IP address.

–

Extended discovery of cluster candidates that are not directly connected to the command switch.

Performance

Note For the Network Assistant software requirements, and for more information about

clustering, see the Getting Started with Cisco Network Assistant, available on Cisco.com. For clustering requirements, including supported Cisco IOS releases, see the release notes for this release.

• Hot Standby Router Protocol (HSRP) for command-switch redundancy. The redundant command

switches used for HSRP must have compatible software releases.

• Autosensing of speed on the 10/100 and 10/100/1000 ports and autonegotiation of duplex mode on

the 10/100 ports for optimizing bandwidth

• IEEE 802.3x flow control on Gigabit Ethernet ports operating in full-duplex mode

• Fast EtherChannel and Gigabit EtherChannel for enhanced fault tolerance and for providing up

to 2 Gbps of bandwidth among switches, routers, and servers

• Support for frames larger than 1500 bytes. These switches support frame sizes from 1500 to

1530 bytes:

–

Catalyst 2950G-12-EI, 2950G-24-EI, 2950G-24-EI-DC, and 2950G-48-EI switches running Cisco IOS Release 12.1(6)EA2 or later

–

Catalyst 2950 LRE switches

–

Catalyst 2955 switches

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Features

Chapter 1 Overview

• Port blocking on forwarding unknown unicast and multicast traffic (available only on the

Catalyst LRE switches and on the Catalyst 2950G-12-EI, 2950G-24-EI, 2950G-24-EI-DC, 2950G-48-EI, and 2955 switches)

• Per-port broadcast storm control for preventing faulty end stations from degrading overall system

performance with broadcast storms

• Port Aggregation Protocol (PAgP) and Link Aggregation Control Protocol (LACP) for automatic

creation of EtherChannel links

• Internet Group Management Protocol (IGMP) snooping for IGMP versions 1, 2, and 3 to limit

flooding of IP multicast traffic

• IGMP report suppression for sending only one IGMP report per multicast router query to the

multicast devices (supported only for IGMPv1 or IGMPv2 queries)

• IGMP snooping querier support to configure switch to generate periodic IGMP General Query

messages

• Multicast VLAN registration (MVR) to continuously send multicast streams in a multicast VLAN

while isolating the streams from subscriber VLANs for bandwidth and security reasons

• IGMP filtering for controlling the set of multicast groups to which hosts on a switch port can belong

• IGMP throttling for configuring the action when the maximum number of entries is in the IGMP

forwarding table

• Protected port (private VLAN edge port) option for restricting the forwarding of traffic to designated

ports on the same switch

• Dynamic address learning for enhanced security

Manageability

• Cisco Intelligence Engine 2100 (IE2100) Series Cisco Networking Services (CNS) embedded

agents for automating switch management, configuration storage and delivery (available only with the EI)

• DHCP-based autoconfiguration for automatically configuring the switch during startup with IP

address information and a configuration file that it receives during DHCP-based autoconfiguration

Note DHCP replaces the Bootstrap Protocol (BOOTP) feature autoconfiguration to ensure

retrieval of configuration files by unicast TFTP messages. BOOTP is available in earlier software releases for this switch.

• DHCP server for automatic assignment of IP addresses and other DHCP options to IP hosts

(available only on the Catalyst 2955 switch)

• Address Resolution Protocol (ARP) for identifying a switch through its IP address and its

corresponding MAC address

• Unicast MAC address filtering to drop packets with specific source or destination MAC addresses

(available only with the EI)

• Cisco Discovery Protocol (CDP) versions 1 and 2 for network topology discovery and mapping

between the switch and other Cisco devices on the network

• Network Time Protocol (NTP) for providing a consistent time stamp to all switches from an external

source

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Chapter 1 Overview

Features

• Directed unicast requests to a TFTP server for obtaining software upgrades from a TFTP server

• Default configuration storage in flash memory to ensure that the switch can be connected to a

network and can forward traffic with minimal user intervention

• In-band management access through the embedded device manager through a Netscape Navigator

or Internet Explorer session or through Network Assistant

• In-band management access through up to 16 simultaneous Telnet connections for multiple

command-line interface (CLI)-based sessions over the network

• In-band management access through up to five simultaneous, encrypted Secure Shell (SSH)

connections for multiple CLI-based sessions over the network (only available in the enhanced cryptographic software image)

• In-band management access through SNMP versions 1, 2c, and 3 get and set requests

• Out-of-band management access through the switch console port to a directly-attached terminal or

to a remote terminal through a serial connection and a modem

Note For additional descriptions of the management interfaces, see the “Management Options”

section on page 1-9.

Redundancy

• HSRP for command-switch redundancy

• UniDirectional Link Detection (UDLD) on all Ethernet ports for detecting and disabling

unidirectional links on fiber-optic interfaces caused by incorrect fiber-optic wiring or port faults

• IEEE 802.1D Spanning Tree Protocol (STP) for redundant backbone connections and loop-free

networks.

–

Up to 64 spanning-tree instances supported

–

Per-VLAN spanning-tree plus (PVST+) for load balancing across VLANs

–

Rapid PVST+ for load balancing across VLANs

–

UplinkFast, cross-stack UplinkFast, and BackboneFast for fast convergence after a spanning-tree topology change and for achieving load balancing among redundant uplinks, including Gigabit uplinks and cross-stack Gigabit uplinks

• IEEE 802.1s Multiple Spanning Tree Protocol (MSTP) for grouping VLANs into a spanning-tree

instance and for providing multiple forwarding paths for data traffic and load balancing and rapid per-VLAN Spanning-Tree plus (rapid-PVST+), based on the IEEE 802.1w Rapid Spanning Tree Protocol (RSTP) for rapid convergence of the spanning tree by immediately transitioning root and designated ports to the forwarding state

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Features

VLAN Support

Chapter 1 Overview

• Optional spanning-tree features available in the PVST+, rapid PVST+, and MSTP modes:

–

Port Fast for eliminating the forwarding delay by enabling a port to immediately transition from the blocking state to the forwarding state

–

BPDU guard for shutting down Port Fast-enabled ports that receive BPDUs

–

BPDU filtering for preventing a Port Fast-enabled port from sending or receiving BPDUs

–

Root guard for preventing switches outside the network core from becoming the spanning-tree root

–

Loop guard for preventing alternate or root ports from becoming designated ports because of a failure that leads to a unidirectional link

• The switches support 250 port-based VLANs for assigning users to VLANs associated with

appropriate network resources, traffic patterns, and bandwidth

Note The Catalyst 2950-12, Catalyst 2950-24, Catalyst 2950SX-24, Catalyst 2950SX-48-SI, and

Catalyst 2950T-48-SI switches support only 64 port-based VLANs.

Security

• The switch supports up to 4094 VLAN IDs to allow service provider networks to support the number of

VLANs allowed by the IEEE 802.1Q standard (available only with the EI)

• IEEE 802.1Q trunking protocol on all ports for network moves, adds, and changes; management and

control of broadcast and multicast traffic; and network security by establishing VLAN groups for high-security users and network resources

• VLAN Membership Policy Server (VMPS) for dynamic VLAN membership

• VLAN Trunking Protocol (VTP) pruning for reducing network traffic by restricting flooded traffic

to links destined for stations receiving the traffic

• Dynamic Trunking Protocol (DTP) for negotiating trunking on a link between two devices and for

negotiating the type of trunking encapsulation (IEEE 802.1Q) to be used

• Voice VLAN for creating subnets for voice traffic from Cisco IP Phones

• VLAN 1 minimization to reduce the risk of spanning-tree loops or storms by allowing VLAN 1 to

be disabled on any individual VLAN trunk link. With this feature enabled, no user traffic is sent or received. The switch CPU continues to send and receive control protocol frames.

• Bridge protocol data unit (BPDU) guard for shutting down a Port Fast-configured port when an

invalid configuration occurs

• Protected port option for restricting the forwarding of traffic to designated ports on the same switch

1-6

• Password-protected access (read-only and read-write access) to management interfaces (device

manager, Network Assistant, and CLI) for protection against unauthorized configuration changes

• Port security option for limiting and identifying MAC addresses of the stations allowed to access

the port

• Port security aging to set the aging time for secure addresses on a port

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Chapter 1 Overview

• DHCP snooping to filter untrusted DHCP messages between untrusted hosts and DHCP servers

• Multilevel security for a choice of security level, notification, and resulting actions

• MAC-based port-level security for restricting the use of a switch port to a specific group of source

addresses and preventing switch access from unauthorized stations

• TACACS+, a proprietary feature for managing network security through a TACACS server

• IEEE 802.1x port-based authentication to prevent unauthorized devices from gaining access to the

network

• IEEE 802.1x accounting to track network usage

• IEEE 802.1x with wake-on-LAN to allow dormant PCs to be powered on based on the receipt of a

specific Ethernet frame

• Standard and extended IP access control lists (ACLs) for defining security policies (available only

with the EI)

Quality of Service and Class of Service

• Automatic QoS (auto-QoS) to simplify the deployment of existing QoS features by classifying

traffic and configuring egress queues (only available in the EI)

Features

• Classification

–

IEEE 802.1p class of service (CoS) with four priority queues on the switch 10/100 and LRE ports and eight priority queues on the Gigabit ports for prioritizing mission-critical and time-sensitive traffic from data, voice, and telephony applications

–

IP Differentiated Services Code Point (IP DSCP) and CoS marking priorities on a per-port basis for protecting the performance of mission-critical applications (only available with the EI)

–

Flow-based packet classification (classification based on information in the MAC, IP, and TCP/UDP headers) for high-performance quality of service at the network edge, allowing for differentiated service levels for different types of network traffic and for prioritizing mission-critical traffic in the network (only available in the EI)

–

Support for IEEE 802.1p CoS scheduling for classification and preferential treatment of high-priority voice traffic

–

Trusted boundary (detect the presence of a Cisco IP Phone, trust the CoS value received, and ensure port security. If the IP phone is not detected, disable the trusted setting on the port and prevent misuse of a high-priority queue.)

• Policing

–

Traffic-policing policies on the switch port for allocating the amount of the port bandwidth to a specific traffic flow

–

Policing traffic flows to restrict specific applications or traffic flows to metered, predefined rates

–

Up to 60 policers on ingress Gigabit-capable Ethernet ports Up to six policers on ingress 10/100 ports Granularity of 1 Mbps on 10/100 ports and 8 Mbps on 10/100/1000 ports

–

Out-of-profile markdown for packets that exceed bandwidth utilization limits

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Note Policing is available only in the EI.

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Features

Monitoring

Chapter 1 Overview

• Egress Policing and Scheduling of Egress Queues—Four egress queues on all switch ports. Support

for strict priority and weighted round-robin (WRR) CoS policies

• Switch LEDs that show port and switch status

• Switched Port Analyzer (SPAN) and Remote SPAN (RSPAN) for traffic monitoring on any port or

VLAN

Note RSPAN is available only in the EI.

• SPAN support of Intrusion Detection Systems (IDSs) to monitor, repel, and report network security

violations

• Four groups (history, statistics, alarms, and events) of embedded remote monitoring (RMON) agents

for network monitoring and traffic analysis

• MAC address notification for tracking the MAC addresses that the switch has learned or removed

• Syslog facility for logging system messages about authentication or authorization errors, resource

issues, and time-out events

• Layer 2 traceroute to identify the physical path that a packet takes from a source device to a

destination device

• Facilities for processing alarms related to temperature, power-supply conditions, and the status of

the Ethernet ports (available only on the Catalyst 2955 switch)

LRE Features (available only on Catalyst 2950 LRE switches)

• Data, voice, and video transmission through categorized and noncategorized unshielded twisted-pair

cable (Category 1, 2, and 3 structured and unstructured cable, such as existing telephone lines) in multi-unit, multidwelling, and multitenant buildings

• Up to 15 Mbps of bandwidth to remote Ethernet devices at distances of up to 4921 feet

(1500 meters) on each switch LRE port

• Compliance with American National Standards Institute (ANSI) and European Telecommunication

Standards Institute (ETSI) standards for spectral-mode compatibility with asymmetric digital subscriber line (ADSL), Integrated Services Digital Network (ISDN), and digital telephone networks

• Configuration and monitoring of connections between:

–

Switch LRE ports and the Ethernet ports on remote LRE customer premises equipment (CPE) devices, such as the Cisco 575 LRE CPE or the Cisco 585 LRE CPE

–

CPE Ethernet ports and remote Ethernet devices, such as a PC

• Support for connecting to the public switched telephone network (PSTN) through plain old

telephone service (POTS) splitters such as the Cisco LRE 48 POTS Splitter

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Chapter 1 Overview

Management Options

• Support for the rate selection, a utility that allows for automatic selection of transmission rates

through sequences

• Support for Reed-Solomon error correction

• Support for a protected port on Cisco 585 CPE devices

• Support for small form-factor pluggable (SFP) modules instead of Gigabit Interface Converter

(GBIC) modules

• Support for configuring the interleave delay feature

• Support for DC-input power and compliance with the VDSL 997 band plan on Catalyst 2950ST-24

LRE 997 switches

• Upstream power back-off mechanism for normalization of the upstream receive power levels by

requiring the CPE devices on shorter lines to transmit at a lower power level than the CPEs on longer lines

• Support for sending LRE debugging messages to the LRE message logging process and to the

system message logging process

Management Options

The switch is designed for plug-and-play operation: you only need to assign basic IP information to the switch and connect it to the other devices in your network. If you have specific network needs, you can configure and monitor the switch—on an individual basis or as part of a switch cluster—through its various management interfaces.

Note For information about assigning an IP address by using the browser-based Express Setup program, see

the getting started guide. For information about assigning an IP address by using the CLI-based setup program, see the hardware installation guide.

This section discusses these topics:

• Management Interface Options, page 1-9

• Advantages of Using Network Assistant and Clustering Switches, page 1-10

Management Interface Options

You can configure and monitor individual switches and switch clusters by using these interfaces:

• An embedded device manager—The device manager is a GUI that is integrated in the software

image. You use it to can configure and to monitor a single switch through a web browser. For more information about the device manager, see the switch online help.

• Network Assistant—Network Assistant is a GUI that can be downloaded from Cisco.com. You use

it to manage a single switch or a cluster of switches. For more information about Network Assistant, see the Getting Started with Cisco Network Assistant, available on Cisco.com.

• CLI—The switch Cisco IOS software supports desktop-switching features. You can access the CLI

either by connecting your management station directly to the switch console port or by using Telnet or SSH from a remote management station.

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For more information about the CLI, see Chapter 2, “Using the Command-Line Interface.”

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Management Options

• IE2100—Cisco Intelligence Engine 2100 Series Configuration Registrar is a network management

device that works with embedded CNS Agents in the switch software. You can automate initial configurations and configuration updates by generating switch-specific configuration changes, sending them to the switch, executing the configuration change, and logging the results.

For more information about IE2100, see Chapter 5, “Configuring IE2100 CNS Agents.”

• SNMP—SNMP provides a means to monitor and control the switch and switch cluster members.

You can manage switch configuration settings, performance, and security and collect statistics by using SNMP management applications such as CiscoWorks2000 LAN Management Suite (LMS) and HP OpenView.

You can manage the switch from an SNMP-compatible management station that is running platforms such as HP OpenView or SunNet Manager. The switch supports a comprehensive set of MIB extensions and four RMON groups.

For more information about using SNMP, see the Chapter 27, “Configuring SNMP.”

Advantages of Using Network Assistant and Clustering Switches

Using Network Assistant and switch clusters can simplify and minimize your configuration and monitoring tasks. You can use Cisco switch clustering technology to manage up to 16 interconnected and supported Catalyst switches through one IP address as if they were a single entity. This can conserve IP addresses if you have a limited number of them. Network Assistant is the easiest interface to use and makes switch and switch cluster management accessible to authorized users from any PC on your network.

Chapter 1 Overview

By using switch clusters and Network Assistant, you can:

• Manage and monitor interconnected Catalyst switches (see the release notes for a list of supported

switches), regardless of their geographic proximity and interconnection media, including Ethernet, Fast Ethernet, Fast EtherChannel, Cisco GigaStack GBIC, Gigabit Ethernet, and Gigabit EtherChannel connections.

• Accomplish multiple configuration tasks from a single Network Assistant window without needing

to remember CLI commands to accomplish specific tasks.

• Apply actions from Network Assistant to multiple ports and multiple switches at the same time to

avoid re-entering the same commands for each individual port or switch. Here are some examples of globally setting and managing multiple ports and switches:

–

Port configuration such as speed and duplex settings

–

Port and console port security settings

–

NTP, STP, VLAN, and quality of service (QoS) configurations

–

Inventory and statistic reporting and link and switch-level monitoring and troubleshooting

–

Group software upgrades

• View a topology of interconnected devices to identify existing switch clusters and eligible switches

that can join a cluster. You can also use the topology to quickly identify link information between switches.

• Monitor real-time status of a switch or multiple switches from the LEDs on the front-panel images.

The system, redundant power system (RPS), and port LED colors on the images are similar to those on the physical LEDs.

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Chapter 1 Overview

• Use an interactive mode that takes you step-by-step through configuring complex features such as

VLANs, ACLs, and QoS.

• Use a wizard that prompts you to provide the minimum required information to configure complex

features such as QoS priorities for video traffic, priority levels for data applications, and security.

For more information about Network Assistant and clustering, see the Getting Started with Cisco Network Assistant, available on Cisco.com.

Network Configuration Examples

This section provides network configuration concepts and includes examples of using the switch to create dedicated network segments and interconnecting the segments through Fast Ethernet and Gigabit Ethernet connections.

• “Design Concepts for Using the Switch” section on page 1-12

• “Small to Medium-Sized Network Configuration” section on page 1-15

• “Collapsed Backbone and Switch Cluster Configuration” section on page 1-16

• “Hotel Network Configuration” section on page 1-17

Network Configuration Examples

• “Service-Provider Central-Office Configuration” section on page 1-20

• “Large Campus Configuration” section on page 1-21

• “Multidwelling Network Using Catalyst 2950 Switches” section on page 1-22

• “Long-Distance, High-Bandwidth Transport Configuration” section on page 1-24

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Network Configuration Examples

Design Concepts for Using the Switch

As your network users compete for network bandwidth, it takes longer to send and receive data. When you configure your network, consider the bandwidth required by your network users and the relative priority of the network applications they use.

Table 1-3 describes what can cause network performance to degrade and how you can configure your

network to increase the bandwidth available to your network users.

Table 1-3 Increasing Network Performance

Network Demands Suggested Design Methods

Too many users on a single network segment and a growing number of users accessing the Internet

• Increased power of new PCs,

workstations, and servers

• High demand from networked

applications (such as e-mail with large attached files) and from bandwidth-intensive applications (such as multimedia)

• Create smaller network segments so that fewer users share the

bandwidth, and use VLANs and IP subnets to place the network resources in the same logical network as the users who access those resources most.

• Use full-duplex operation between the switch and its connected

workstations.

• Connect global resources—such as servers and routers to which network

users require equal access—directly to the Fast Ethernet or Gigabit Ethernet switch ports so that they have their own Fast Ethernet or Gigabit Ethernet segment.

• Use the Fast EtherChannel or Gigabit EtherChannel feature between the

switch and its connected servers and routers.

Chapter 1 Overview

Bandwidth alone is not the only consideration when designing your network. As your network traffic profiles evolve, consider providing network services that can support applications such as voice and data integration and security.

Table 1-4 describes some network demands and how you can meet those demands.

Table 1-4 Providing Network Services

Network Demands Suggested Design Methods

High demand for multimedia support

High demand for protecting mission-critical applications

• Use IGMP and MVR to efficiently forward multicast traffic.

• Use VLANs and protected ports to provide security and port isolation.

• Use VLAN trunks, cross-stack UplinkFast, and BackboneFast for

traffic-load balancing on the uplink ports so that the uplink port with a lower relative port cost is selected to carry the VLAN traffic.

An evolving demand for IP telephony

• Use QoS to prioritize applications such as IP telephony during

congestion and to help control both delay and jitter within the network.

• Use switches that support at least two queues per port to prioritize voice

and data traffic as either high- or low-priority, based on 802.1p or

802.1Q.

A growing demand for using existing infrastructure to transport data and voice from a home or office to the Internet or an intranet at

• Use the Catalyst 2900 LRE XL or Catalyst 2950 LRE switches to

provide up to 15 Mb of IP connectivity over existing infrastructure (existing telephone lines).

higher speeds

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Chapter 1 Overview

Network Configuration Examples

Figure 1-1 shows configuration examples of using the Catalyst switches to create these networks:

• Cost-effective wiring closet—A cost-effective way to connect many users to the wiring closet is to

connect up to nine Catalyst 2900 XL, Catalyst 2950, Catalyst 3500 XL, and Catalyst 3550 switches through GigaStack GBIC connections. When you use a stack of Catalyst 2950G-48 switches, you can connect up to 432 users. To preserve switch connectivity if one switch in the stack fails, connect the bottom switch to the top switch to create a GigaStack loopback, and enable cross-stack UplinkFast on the cross-stack Gigabit uplinks.

You can create backup paths by using Fast Ethernet, Gigabit, Fast EtherChannel, or Gigabit EtherChannel links. Using Gigabit modules on two of the switches, you can have redundant uplink connections to a Gigabit backbone switch such as the Catalyst 3550-12G switch. If one of the redundant connections fails, the other can serve as a backup path. You can configure the stack members and the Catalyst 3550-12G switch as a switch cluster to manage them through a single IP address.

• High-performance workgroup—For users who require high-speed access to network resources, use

Gigabit modules to connect the switches directly to a backbone switch in a star configuration. Each switch in this configuration provides users with a dedicated 1-Gbps connection to network resources in the backbone. Compare this with the switches in a GigaStack configuration, where the 1-Gbps connection is shared among the switches. With the high speed uplink to the distribution server, the user can efficiently obtain and store data from servers. Using these Gigabit Ethernet modules also provides flexibility in media and distance options:

–

1000BASE-T GBIC: copper connections of up to 328 feet (100 meters)

–

1000BASE-SX GBIC: fiber connections of up to 1804 feet (550 meters)

–

1000BASE-LX/LH GBIC: fiber connections of up to 32,808 feet (10 kilometers)

–

1000BASE-ZX GBIC: fiber connections of up to 328,084 feet (100 kilometers)

–

GigaStack GBIC module for creating a 1-Gbps stack configuration of up to nine supported switches. The GigaStack GBIC supports one full-duplex link (in a point-to-point configuration) or up to nine half-duplex links (in a stack configuration) to other Gigabit Ethernet devices. Using the required Cisco proprietary signaling and cabling, the GigaStack GBIC-to-GigaStack GBIC connection cannot exceed 3 feet (1 meter).

–

SFP modules: fiber and copper connections of up to 32,808 feet (10 kilometers) (supported only on the Catalyst 2950 LRE switches)

• Redundant Gigabit backbone—Using HSRP, you can create backup paths between

Catalyst 3550-12T-L3 switches. To enhance network reliability and load balancing for different VLANs and subnets, you can connect the Catalyst 2950 switches, again in a star configuration, to two backbone switches. If one of the backbone switches fails, the second backbone switch preserves connectivity between the switches and network resources.

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Network Configuration Examples

Figure 1-1 Example Configurations

Chapter 1 Overview

Catalyst 2950 switch

Cost-Effective Wiring Closet

High-Performance Workgroup

Catalyst 2900 XL, Catalyst 2950, Catalyst 2955,

Catalyst 3500 XL, and Catalyst 3550 cluster

Catalyst 3550-12T or

Catalyst 3550-12G switch

Catalyst 3550-12T or

Catalyst 3550-12G switch

1-Gbps HSRP

Catalyst 2900 XL, Catalyst 2950, Catalyst 3500 XL, and Catalyst 3550 GigaStack cluster

Gigabit server

Catalyst 3550-12T or

1-14

Redundant Gigabit Backbone

Catalyst 2900 XL, Catalyst 2950, Catalyst 2955,

Catalyst 3500 XL, and Catalyst 3550 cluster

Catalyst 2950 and Catalyst 2955 Switch Software Configuration Guide

60992

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Chapter 1 Overview

Small to Medium-Sized Network Configuration

Figure 1-2 shows a configuration for a network that has up to 250 users. Users in this network require

e-mail, file-sharing, database, and Internet access.

You optimize network performance by placing workstations on the same logical segment as the servers they access most often. This divides the network into smaller segments (or workgroups) and reduces the amount of traffic that travels over a network backbone, thereby increasing the bandwidth available to each user and improving server response time.

Figure 1-2 Small to Medium-Sized Network Configuration

Cisco 2600 router

100 Mbps (200 Mbps full duplex)

Gigabit server

Network Configuration Examples

1 Gbps (2 Gbps full duplex)

Catalyst 2900 XL,

Catalyst 2950,

Catalyst 3550, and

Catalyst 3500 XL

GigaStack cluster

10/100 Mbps (20/200 Mbps full duplex)

Single workstations

Gigabit server

60993

A network backbone is a high-bandwidth connection (such as Fast Ethernet or Gigabit Ethernet) that interconnects segments and network resources. It is required if numerous segments require access to the servers. The Catalyst 2900 XL, Catalyst 2950, Catalyst 3500 XL, and Catalyst 3550 switches in this network are connected through a GigaStack GBIC on each switch to form a 1-Gbps network backbone. This GigaStack can also be configured as a switch cluster, with primary and secondary command switches for redundant cluster management.

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Workstations are connected directly to the 10/100 switch ports for their own 10- or 100-Mbps access to network resources (such as web and mail servers). When a workstation is configured for full-duplex operation, it receives up to 200 Mbps of dedicated bandwidth from the switch.

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Network Configuration Examples

Servers are connected to the GBIC module ports on the switches, allowing 1-Gbps throughput to users when needed. When the switch and server ports are configured for full-duplex operation, the links provide 2 Gbps of bandwidth. For networks that do not require Gigabit performance from a server, connect the server to a Fast Ethernet or Fast EtherChannel switch port.

Connecting a router to a Fast Ethernet switch port provides multiple, simultaneous access to the Internet through one line.

Collapsed Backbone and Switch Cluster Configuration

Figure 1-3 shows a configuration for a network of approximately 500 employees. This network uses a

collapsed backbone and switch clusters. A collapsed backbone has high-bandwidth uplinks from all segments and subnetworks to a single device, such as a Gigabit switch, that serves as a single point for monitoring and controlling the network. You can use a Catalyst 3550-12T-L3 switch, as shown, or a Catalyst 3508G XL switch to create a Gigabit backbone. A Catalyst 3550-12T-L3 backbone switch provides the benefits of inter-VLAN routing and allows the router to focus on WAN access.

The workgroups are created by clustering all the Catalyst switches except the Catalyst 4908G-L3 switch. Using Network Assistant and Cisco switch clustering technology, you can group the switches into multiple clusters, as shown, or into a single cluster. You can manage a cluster through the IP address of its active and standby command switches, regardless of the geographic location of the cluster members.

Chapter 1 Overview

This network uses VLANs to segment the network logically into well-defined broadcast groups and for security management. Data and multimedia traffic are configured on the same VLAN. Voice traffic from the Cisco IP Phones are configured on separate voice VLAN IDs (VVIDs). You can have up to four VVIDs per wiring closet. If data, multimedia, and voice traffic are assigned to the same VLAN, only one VLAN can be configured per wiring closet. For any switch port connected to Cisco IP Phones,

802.1p or 802.1Q QoS gives forwarding priority to voice traffic over data traffic.

Grouping servers in a centralized location provides benefits such as security and easier maintenance. The Gigabit connections to a server farm provide the workgroups full access to the network resources (such as a call-processing server running Cisco CallManager software, a DHCP server, or an IP/TV multicast server).

Cisco IP Phones are connected—using standard straight-through, twisted-pair cable with RJ-45 connectors—to the 10/100 inline-power ports on the Catalyst 3550-24PWR switches and to the 10/100 ports on the Catalyst 2950 switches. These multiservice switch ports automatically detect any IP phones that are connected. Cisco CallManager controls call processing, routing, and IP phone features and configuration. Users with workstations running Cisco SoftPhone software can place, receive, and control calls from their PCs. Using Cisco IP Phones, Cisco CallManager software, and Cisco SoftPhone software integrates telephony and IP networks, and the IP network supports both voice and data.

Each 10/100 inline-power port on the Catalyst 3550-24PWR switches provides –48 VDC power to the Cisco IP Phone. The IP phone can receive redundant power when it is also connected to an AC power source. IP phones not connected to the Catalyst 3550-24PWR switches receive power from an AC power source.

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Chapter 1 Overview

Figure 1-3 Collapsed Backbone and Switch Cluster Configuration

Gigabit servers

Cisco CallManager

Catalyst 3550-12T or Catalyst 3550-12G switch

Network Configuration Examples

(2 Gbps full duplex)

Catalyst 2950, 2900 XL,

3550, and 3500 XL

GigaStack cluster

Workstations running

Cisco SoftPhone software

1 Gbps

GigaStack cluster

Catalyst

2950,

2900 XL,

3550, and

3500 XL

IP IP IP

Cisco IP Phones

Cisco 2600 router

200 Mbps Fast EtherChannel (400-Mbps full-duplex Fast EtherChannel)

Catalyst 3550-24PWR cluster

Cisco

IP Phones

60994

Hotel Network Configuration

Figure 1-4 shows Catalyst 2950ST-8 LRE and 2950ST-24 LRE switches in a hotel network environment

with approximately 200 rooms. This network includes a PBX switchboard, a router, and high-speed servers.

Connected to the telephone line in each hotel room is an LRE CPE device, such as a Cisco LRE CPE device. The LRE CPE device provides:

• Two RJ-11 ports, one for connecting to the telephone jack on the wall and one for connecting to a

POTS telephone.

• One or more RJ-45 Ethernet ports for connecting to devices such as a customer’s laptop, the room

IP phone, the television set-top box, or a room environmental control device. A Cisco 575 LRE CPE provides one Ethernet connection; a Cisco 585 LRE CPE provides four.

When connected to the CPE device, the Ethernet devices and room telephone share the same telephone line.

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Network Configuration Examples

Note All telephones not directly connected to the hotel room CPE device require microfilters with a 300-ohm

termination. Microfilters improve voice call quality when voice and data equipment are using the same telephone line. They also prevent nonfiltered telephone rings and nonfiltered telephone transitions (such as on-hook to off-hook) from interrupting the Ethernet connection.

Through a patch panel, the telephone line from each room connects to a nonhomologated POTS splitter, such as the Cisco LRE 48 POTS Splitter. The splitter routes data (high-frequency) and voice (low-frequency) traffic from the telephone line to a Catalyst 2950 LRE switch and digital private branch exchange (PBX). The PBX routes voice traffic to the PSTN.

If a PBX is not on-site, a homologated POTS splitter is required to connect directly to the PSTN.

Note Consult the regulations for connecting to the PSTN in your area.

If a connection to a phone network is not required at all, a splitter is not needed, and the switch can connect directly to the patch panel.

Chapter 1 Overview

Note Cisco LRE products can share lines with analog telephones, Integrated Services Digital Network (ISDN)

telephone network, and PBX switches that use the 0 to 700 kHz frequency range.

Data to and from the room devices (such as e-mail for the laptop and IP multicast traffic for the television) are transferred through the LRE link, which is established between the CPE RJ-11 wall port and the LRE port on an LRE switch. The upstream and downstream rates on the LRE link are controlled by a profile configured on each LRE port. If the LRE switch was connected to the PSTN through a homologated POTS splitter, all LRE ports would use an ANSI-compliant LRE profile named LRE-998-15-4.

The Catalyst 2950 LRE switches are cascaded through their 10/100/1000 switch ports. Each switch also has a 10/100/1000 connection to an aggregation switch, such as a Catalyst 3550-12G switch. The aggregation switch can connect to these devices:

• Accounting, billing, and provisioning servers

• A router that provides Internet access to the premises

You can manage the switches as a switch cluster and through Network Assistant. You can also manage and monitor the individual CPE devices from the LRE switches to which they are connected. The Catalyst 2950 LRE switch ports support the same software features as 10/100/1000 switch ports. For example, you can configure port-based VLANs on the LRE ports to provide individual port security and protected ports to further prevent unwanted broadcasts within the VLANs.

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Chapter 1 Overview

Figure 1-4 Network Hotel Configuration

Network Configuration Examples

Rooms

and

users

Rooms

and

users

Set-top

box

POTS telephone

Required

microfilter

Laptop

Cisco 575

LRE CPE

Laptop

Cisco 585 LRE CPE

POTS telephones

Required microfilter

phone

Environmental

controls

Set-top

POTS telephone

box

Cisco 575

LRE CPE

Required

microfilter

Laptop

POTS telephones

Laptop

phone

Environmental

Cisco 585 LRE CPE

Required microfilter

Floor 4

controls

Floor 3

Patch panel

Cisco

LRE 48

POTS

splitters

PSTN

PBX

Catalyst 2950 or

Catalyst 3550 switch

Catalyst 2950ST-8 LRE and 2950ST-24 LRE switches

Servers

Cisco 2600 router

89514

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Network Configuration Examples

Service-Provider Central-Office Configuration

Figure 1-5 shows the Catalyst 2950ST-24 LRE 997 switches in a service-provider central-office network

environment. The Catalyst 2950ST-24 LRE 997 switches have DC-input power supply and are compliant with the VDSL 997 band plan. The Catalyst 2950 LRE switches are located in a central office and are connected to the Cisco 576 LRE 997 CPE devices located in different buildings. The switches also connect to a Cisco 7500 router.

You can use a POTS splitter to connect the switches to the CPE devices. The splitter routes data (high-frequency) to a Catalyst 2950 LRE switch and voice (low-frequency) traffic from the telephone line to a PSTN.

Connected to the telephone line in each office is an Cisco 576 LRE 997 CPE device. The LRE CPE device provides:

• Two RJ-11 ports, one for connecting to the telephone jack on the wall and one for connecting to a

POTS telephone.

• One RJ-45 Ethernet port for connecting to devices such as a customer’s laptop, the office’s IP phone,

the television set-top box, or a office environmental control device. A Cisco 576 LRE 997 provides one Ethernet connection.

Chapter 1 Overview

When connected to the CPE device, the Ethernet devices and office telephone share the same telephone line.

Note All telephones not directly connected to the office CPE device require microfilters with a 300-ohm

Note Cisco LRE products can share lines with analog telephones and Integrated Services Digital Network

(ISDN) telephone network that use the 0 to 120 kHz frequency range.

Data to and from the office devices (such as e-mail for the laptop and IP multicast traffic for the television) are transferred through the LRE link, which is established between the CPE RJ-11 wall port and the LRE port on an LRE switch. The upstream and downstream rates on the LRE link are controlled by a profile configured on each LRE port.

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Chapter 1 Overview

Network Configuration Examples

Figure 1-5 Service Provider Central Office Configuration

Central office

Copper twisted pair

Cisco router

7500

POTS

splitter

POTS

splitter

Catalyst 2950ST-24

LRE 997 switches

(DC-input power)

Large Campus Configuration

Cisco 576 LRE 997 CPE

Building 1

Building 2

Building 3

Building 4

Laptop

Cisco 576

LRE 997

Offices and users

POTS telephones

Required microfilter

89380

Figure 1-6 shows a configuration for a network of more than 1000 users. Because it can aggregate up to

130 Gigabit connections, a Catalyst 6500 multilayer switch is used as the backbone switch.

You can use the workgroup configurations shown in previous examples to create workgroups with Gigabit uplinks to the Catalyst 6500 switch. For example, you can use switch clusters that have a mix of Catalyst 2950 and Catalyst 2955 switches.

The Catalyst 6500 switch provides the workgroups with Gigabit access to core resources:

• Cisco 7000 series router for access to the WAN and the Internet.

• Server farm that includes a call-processing server running Cisco CallManager software. Cisco

CallManager controls call processing, routing, and IP phone features and configuration.

• Cisco Access gateway (such as Cisco Access Digital Trunk Gateway or Cisco Access Analog Trunk

Gateway) that connects the IP network to the Public Switched Telephone Network (PSTN) or to users in an IP telephony network.

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Network Configuration Examples

Figure 1-6 Large Campus Configuration

Chapter 1 Overview

WAN

Cisco

CallManager

Catalyst 2950, 2900 XL,

3500 XL, and 3550

GigaStack cluster

Servers

Catalyst

6500 switch

Cisco 7200

or 7500 router

IP telephony

network or

PSTN

Cisco access

gateway

1 Gbps (2 Gbps full duplex)

Catalyst 3550-24PWR cluster

IP IP IP

Workstations running

Cisco SoftPhone software

Cisco IP Phones

Multidwelling Network Using Catalyst 2950 Switches

A growing segment of residential and commercial customers are requiring high-speed access to Ethernet metropolitan-area networks (MANs). Figure 1-7 shows a configuration for a Gigabit Ethernet MAN ring using Catalyst 3550 multilayer switches as aggregation switches in the mini-point-of-presence (POP) location. These switches are connected through 1000BASE-X GBIC ports.

The resident switches can be Catalyst 2950 switches, providing customers with high-speed connections to the MAN. Catalyst 2900 LRE XL or 2950 LRE Layer 2-only switches also can be used as residential switches for customers requiring connectivity through existing telephone lines. The Catalyst LRE switches can then connect to another residential switch or to an aggregation switch. For more information about these switches, see the Catalyst 2950 Desktop Switch Hardware Installation Guide.

Cisco IP Phones

60995

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Chapter 1 Overview

Network Configuration Examples

All ports on the residential Catalyst 2950 and 2955 switches (and Catalyst LRE switches if they are included) are configured as 802.1Q trunks with protected port and STP root guard features enabled. The protected port feature provides security and isolation between ports on the switch, ensuring that subscribers cannot view packets destined for other subscribers. STP root guard prevents unauthorized devices from becoming the STP root switch. All ports have IGMP snooping or CGMP enabled for multicast traffic management. ACLs on the uplink ports to the aggregating Catalyst 3550 multilayer switches provide security and bandwidth management.

The aggregating switches and routers provide services such as those described in the previous examples, “Small to Medium-Sized Network Configuration” and “Large Campus Configuration.”

Figure 1-7 Catalyst 2950 Switches in a MAN Configuration

Cisco 12000

Gigabit switch routers

Catalyst 6500

switches

Catalyst 3550

multilayer

switches

Catalyst

switches

Set-top box

Si Si

Service Provider POP

Mini-POP Gigabit MAN

Residential location

Residential gateway (hub)

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Where to Go Next

Long-Distance, High-Bandwidth Transport Configuration

Note To use the feature described in this section, you must have the EI installed on your switch.

Figure 1-8 shows a configuration for transporting 8 Gigabits of data over a single fiber-optic cable. The

Catalyst switches have Coarse Wave Division Multiplexer (CWDM) fiber-optic GBIC modules installed. Depending on the CWDM GBIC module, data is sent at wavelengths from 1470 nm to 1610 nm. The higher the wavelength, the farther the transmission can travel. A common wavelength used for long-distance transmissions is 1550 nm.

The CWDM GBIC modules connect to CWDM optical add/drop multiplexer (OADM) modules over distances of up to 393,701 feet (74.5 miles or 120 km). The CWDM OADM modules combine (or multiplex) the different CWDM wavelengths, allowing them to travel simultaneously on the same fiber-optic cable. The CWDM OADM modules on the receiving end separate (or demultiplex) the different wavelengths.

For more information about the CWDM GBIC modules and CWDM OADM modules, see the Cisco CWDM GBIC and CWDM SFP Installation Note.

Chapter 1 Overview

Figure 1-8 Long-Distance, High-Bandwidth Transport Configuration

Access layer

Catalyst switches

Where to Go Next

Before configuring the switch, review these sections for start up information:

• Chapter 2, “Using the Command-Line Interface”

Eight

1-Gbps

connections

CWDM

OADM

modules

8 Gbps

CWDM

OADM

modules

Aggregation layer

Catalyst 4500

multilayer

switches

95750

1-24

• Chapter 4, “Assigning the Switch IP Address and Default Gateway”

• Chapter 5, “Configuring IE2100 CNS Agents”

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CHAPTER

Using the Command-Line Interface

This chapter describes the Cisco IOS command-line interface (CLI) that you can use to configure your Catalyst 2950 and Catalyst 2955 switches. It contains these sections:

• Cisco IOS Command Modes, page 2-1

• Getting Help, page 2-3

• Abbreviating Commands, page 2-4

• Using no and default Forms of Commands, page 2-4

• Understanding CLI Messages, page 2-5

• Using Command History, page 2-5

• Using Editing Features, page 2-6

• Searching and Filtering Output of show and more Commands, page 2-9

• Accessing the CLI, page 2-9

Cisco IOS Command Modes

The user interface is divided into many different modes. The commands available to you depend on which mode you are currently in. Enter a question mark (?) at the system prompt to obtain a list of commands available for each command mode.

When you start a session on the switch, you begin in user mode, often called user EXEC mode. Only a limited subset of the commands are available in user EXEC mode. For example, most of the user EXEC commands are one-time commands, such as show commands, which show the current configuration status, and clear commands, which clear counters or interfaces. The user EXEC commands are not saved when the switch reboots.

To have access to all commands, you must enter privileged EXEC mode. Normally, you must enter a password to enter privileged EXEC mode. From this mode, you can enter any privileged EXEC command or enter global configuration mode.

Using the configuration modes (global, interface, and line), you can make changes to the running configuration. If you save the configuration, these commands are stored and used when the switch reboots. To access the various configuration modes, you must start at global configuration mode. From global configuration mode, you can enter interface configuration mode and line configuration mode.

For information on accessing the CLI through the switch console port or through a Telnet session, see the hardware installation guide or the getting started guide.

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Chapter 2 Using the Command-Line Interface

Cisco IOS Command Modes

Tabl e 2-1 describes the main command modes, how to access each one, the prompt you see in that mode, and

how to exit the mode. The examples in the table use the host name Switch.

Table 2-1 Command Mode Summary

Mode Access Method Prompt Exit Method About This Mode

User EXEC Begin a session with

your switch.

Privileged EXEC While in user EXEC

mode, enter the enable command.

Global configuration While in privileged

EXEC mode, enter the configure command.

Config-vlan While in global

configuration mode, enter the vlan vlan-id command.

VLAN configuration While in privileged

EXEC mode, enter the vlan database command.

Switch>

Switch#

Switch(config)#

Switch(config-vlan)#

Switch(vlan)#

Enter logout or quit. Use this mode to

• Change terminal

settings.

• Perform basic tests.

• Display system

information.

Enter disable to exit. Use this mode to verify

commands that you have entered. Use a password to protect access to this mode.

To exit to privileged EXEC mode, enter exit or end, or press

Use this mode to configure parameters that apply to the entire switch.

Ctrl-Z.

To exit to global configuration mode, enter the exit command.

To return to privileged EXEC mode, press Ctrl-Z or enter end.

To exit to privileged EXEC mode, enter exit.

Use this mode to configure VLAN parameters. When VTP mode is transparent, you can create extended-range VLANs (VLAN IDs greater than

1005) and save configurations in the switch startup configuration file.

Use this mode to configure VLAN parameters for VLANs 1 to 1005 in the VLAN database.

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Chapter 2 Using the Command-Line Interface

Table 2-1 Command Mode Summary (continued)

Mode Access Method Prompt Exit Method About This Mode

Interface configuration

While in global configuration mode, enter the interface command (with a specific interface).

Line configuration While in global

configuration mode, specify a line with the line vty or line console command.

Switch(config-if)#

Switch(config-line)#

To exit to global configuration mode, enter exit.

To return to privileged EXEC mode, press Ctrl-Z or enter end.

To exit to global configuration mode, enter exit.

To return to privileged EXEC mode, press Ctrl-Z or enter end.

Use this mode to configure parameters for the switch interfaces and Long-Reach Ethernet (LRE) customer premises equipment (CPE) device interfaces.

To configure multiple interfaces with the same parameters, see the

“Configuring a Range of Interfaces” section on page 10-6.

Use this mode to configure parameters for the terminal line.

Getting Help

You can enter a question mark (?) at the system prompt to display a list of commands available for each command mode. You can also obtain a list of associated keywords and arguments for any command, as shown in Table 2-2.

Ta b l e 2 - 2 H el p S um m a ry

Command Purpose

help Obtain a brief description of the help system in any command mode.

abbreviated-command-entry? Obtain a list of commands that begin with a particular character string.

For example:

Switch# di? dir disable disconnect

abbreviated-command-entry<Ta b> Complete a partial command name.

For example:

Switch# sh conf<tab> Switch# show configuration

? List all commands available for a particular command mode.

For example:

Switch> ?

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Abbreviating Commands

Table 2-2 Help Summary (continued)

Command Purpose

command ? List the associated keywords for a command.

For example:

Switch> show ?

command keyword ? List the associated arguments for a keyword.

For example:

Switch(config)# cdp holdtime ? <10-255> Length of time (in sec) that receiver must keep this packet

Abbreviating Commands

You have to enter only enough characters for the switch to recognize the command as unique. This example shows how to enter the show configuration privileged EXEC command:

Switch# show conf

Chapter 2 Using the Command-Line Interface

Using no and default Forms of Commands

Almost every configuration command also has a no form. In general, use the no form to disable a feature or function or reverse the action of a command. For example, the no shutdown interface configuration command reverses the shutdown of an interface. Use the command without the keyword no to re-enable a disabled feature or to enable a feature that is disabled by default.

Configuration commands can also have a default form. The default form of a command returns the command setting to its default. Most commands are disabled by default, so the default form is the same as the no form. However, some commands are enabled by default and have variables set to certain default values. In these cases, the default command enables the command and sets variables to their default values.

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Chapter 2 Using the Command-Line Interface

Understanding CLI Messages

Table 2-3 lists some error messages that you might encounter while using the CLI to configure your

switch.

Table 2-3 Common CLI Error Messages

Error Message Meaning How to Get Help

% Ambiguous command: "show con"

% Incomplete command.

% Invalid input detected at ‘^’ marker.

You did not enter enough characters for your switch to recognize the command.

You did not enter all the keywords or values required by this command.

You entered the command incorrectly. The caret (^) marks the point of the error.

Re-enter the command followed by a question mark (?) with a space between the command and the question mark.

The possible keywords that you can enter with the command appear.

Re-enter the command followed by a question mark (?) with a space between the command and the question mark.

The possible keywords that you can enter with the command appear.

Enter a question mark (?) to display all the commands that are available in this command mode.

The possible keywords that you can enter with the command appear.

Understanding CLI Messages

Using Command History

The software provides a history or record of commands that you have entered. This feature is particularly useful for recalling long or complex commands or entries, including access lists. You can customize the command history feature to suit your needs as described in these sections:

• Changing the Command History Buffer Size, page 2-5

• Recalling Commands, page 2-6

• Disabling the Command History Feature, page 2-6

Changing the Command History Buffer Size

By default, the switch records ten command lines in its history buffer. Beginning in privileged EXEC mode, enter this command to change the number of command lines that the switch records during the current terminal session:

Switch# terminal history [size

The range is from 0 to 256.

Beginning in line configuration mode, enter this command to configure the number of command lines the switch records for all sessions on a particular line:

Switch(config-line)# history [size

The range is from 0 to 256.

number-of-lines

]

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Chapter 2 Using the Command-Line Interface

Using Editing Features

Recalling Commands

To recall commands from the history buffer, perform one of the actions listed in Ta b le 2-4:

Table 2-4 Recalling Commands

Action

Press Ctrl-P or the up arrow key. Recall commands in the history buffer, beginning with the most recent command.

Press Ctrl-N or the down arrow key. Return to more recent commands in the history buffer after recalling commands

show history While in privileged EXEC mode, list the last several commands that you just

1. The arrow keys function only on ANSI-compatible terminals such as VT100s.

Result

Repeat the key sequence to recall successively older commands.

with Ctrl-P or the up arrow key. Repeat the key sequence to recall successively more recent commands.

entered. The number of commands that appear is determined by the setting of the terminal history global configuration command and history line configuration command.

Disabling the Command History Feature

The command history feature is automatically enabled.

To disable the feature during the current terminal session, enter the terminal no history privileged EXEC command.

To disable command history for the line, enter the no history line configuration command.

Using Editing Features

This section describes the editing features that can help you manipulate the command line. It contains these sections:

• Enabling and Disabling Editing Features, page 2-6

• Editing Commands through Keystrokes, page 2-7

• Editing Command Lines that Wrap, page 2-8

Enabling and Disabling Editing Features

Although enhanced editing mode is automatically enabled, you can disable it.

To re-enable the enhanced editing mode for the current terminal session, enter this command in privileged EXEC mode:

Switch# terminal editing

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Chapter 2 Using the Command-Line Interface

To reconfigure a specific line to have enhanced editing mode, enter this command in line configuration mode:

Switch(config-line)# editing

To globally disable enhanced editing mode, enter this command in line configuration mode:

Switch(config-line)# no editing

Editing Commands through Keystrokes

Table 2-5 shows the keystrokes that you need to edit command lines.

Table 2-5 Editing Commands through Keystrokes

Using Editing Features

Capability Keystroke

Move around the command line to make changes or corrections.

Press Ctrl-B, or press the left arrow key.

Press Ctrl-F, or press the right arrow key.

Press Ctrl-A. Move the cursor to the beginning of the command line.

Press Ctrl-E. Move the cursor to the end of the command line.

Press Esc B. Move the cursor back one word.

Press Esc F. Move the cursor forward one word.

Press Ctrl-T. Transpose the character to the left of the cursor with the

Recall commands from the buffer and paste them in the command line. The switch provides a buffer with the last

Press Ctrl-Y. Recall the most recent entry in the buffer.

Press Esc Y. Recall the next buffer entry.

ten items that you deleted.

Delete entries if you make a mistake or change your mind.

Press the Delete or Backspace key.

Press Ctrl-D. Delete the character at the cursor.

Press Ctrl-K. Delete all characters from the cursor to the end of the

Press Ctrl-U or Ctrl-X. Delete all characters from the cursor to the beginning of

Press Ctrl-W. Delete the word to the left of the cursor.

Press Esc D. Delete from the cursor to the end of the word.

Capitalize or lowercase words or capitalize a set of letters.

Press Esc C. Capitalize at the cursor.

Press Esc L. Change the word at the cursor to lowercase.

Press Esc U. Capitalize letters from the cursor to the end of the word.

Designate a particular keystroke as

Press Ctrl-V or Esc Q.

an executable command, perhaps as a shortcut.

Purpose

Move the cursor back one character.

Move the cursor forward one character.

character located at the cursor.

The buffer contains only the last 10 items that you have deleted or cut. If you press Esc Y more than ten times, you cycle to the first buffer entry.

Erase the character to the left of the cursor.

command line.

the command line.

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Using Editing Features

Table 2-5 Editing Commands through Keystrokes (continued)

Chapter 2 Using the Command-Line Interface

Capability Keystroke

Scroll down a line or screen on displays that are longer than the terminal screen can display.

Note The More prompt is used for

Press the Return key. Scroll down one line.

Press the Space bar. Scroll down one screen.

any output that has more lines than can be displayed on the terminal screen, including show command output. You can use the Return and Space bar keystrokes whenever you see the More prompt.

Redisplay the current command line

Press Ctrl-L or Ctrl-R. Redisplay the current command line.

if the switch suddenly sends a message to your screen.

1. The arrow keys function only on ANSI-compatible terminals such as VT100s.

Editing Command Lines that Wrap

You can use a wraparound feature for commands that extend beyond a single line on the screen. When the cursor reaches the right margin, the command line shifts ten spaces to the left. You cannot see the first ten characters of the line, but you can scroll back and check the syntax at the beginning of the command.

Purpose

To scroll back to the beginning of the command entry, press Ctrl-B or the left arrow key repeatedly. You can also press Ctrl-A to immediately move to the beginning of the line.

Note The arrow keys function only on ANSI-compatible terminals such as VT100s.

In this example, the access-list global configuration command entry extends beyond one line. When the cursor first reaches the end of the line, the line is shifted ten spaces to the left and redisplayed. The dollar sign ($) shows that the line has been scrolled to the left. Each time the cursor reaches the end of the line, the line is again shifted ten spaces to the left.

Switch(config)# access-list 101 permit tcp 131.108.2.5 255.255.255.0 131.108.1 Switch(config)# $ 101 permit tcp 131.108.2.5 255.255.255.0 131.108.1.20 255.25 Switch(config)# $t tcp 131.108.2.5 255.255.255.0 131.108.1.20 255.255.255.0 eq Switch(config)# $108.2.5 255.255.255.0 131.108.1.20 255.255.255.0 eq 45

After you complete the entry, press Ctrl-A to check the complete syntax before pressing the Return key to execute the command. The dollar sign ($) appears at the end of the line to show that the line has been scrolled to the right:

Switch(config)# access-list 101 permit tcp 131.108.2.5 255.255.255.0 131.108.1$

The software assumes you have a terminal screen that is 80 columns wide. If you have a width other than that, use the terminal width privileged EXEC command to set the width of your terminal.

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Searching and Filtering Output of show and more Commands

Use line wrapping with the command history feature to recall and modify previous complex command entries. For information about recalling previous command entries, see the “Editing Commands through

Keystrokes” section on page 2-7.

Searching and Filtering Output of show and more Commands

You can search and filter the output for show and more commands. This is useful when you need to sort through large amounts of output or if you want to exclude output that you do not need to see.

To use this functionality, enter a show or more command followed by the pipe character (|), one of the keywords begin, include, or exclude, and an expression that you want to search for or filter out:

command | {begin | include | exclude} regular-expression

Expressions are case sensitive. For example, if you enter | exclude output, the lines that contain output are not displayed, but the lines that contain Output appear.

This example shows how to include in the output display only lines where the expression protocol appears:

Switch# show interfaces | include protocol Vlan1 is up, line protocol is up Vlan10 is up, line protocol is down GigabitEthernet0/1 is up, line protocol is down GigabitEthernet0/2 is up, line protocol is up

Accessing the CLI

Before you can access the CLI, you need to connect a terminal or PC to the switch console port and power on the switch as described in the hardware installation guide that shipped with your switch. Then, to understand the boot process and the options available for assigning IP information, see Chapter 4,

“Assigning the Switch IP Address and Default Gateway.”

If your switch is already configured, you can access the CLI through a local console connection or through a remote Telnet session, but your switch must first be configured for this type of access. For more information, see the “Setting a Telnet Password for a Terminal Line” section on page 8-6.

You can establish a connection with the switch by either

• Connecting the switch console port to a management station or dial-up modem. For information

about connecting to the console port, see the switch hardware installation guide.

• Using any Telnet TCP/IP or encrypted Secure Shell (SSH) package from a remote management

station. The switch must have network connectivity with the Telnet or SSH client, and the switch must have an enable secret password configured.

For information about configuring the switch for Telnet access, see the “Setting a Telnet Password

for a Terminal Line” section on page 8-6. The switch supports up to 16 simultaneous Telnet sessions.

Changes made by one Telnet user are reflected in all other Telnet sessions.

For information about configuring the switch for SSH, see the “Configuring the Switch for Secure

Shell” section on page 8-33. The switch supports up to five simultaneous secure SSH sessions.

After you connect through the console port, or through a Telnet session, or through an SSH session, the user EXEC prompt appears on the management station.

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Accessing the CLI

Chapter 2 Using the Command-Line Interface

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CHAPTER

Configuring Catalyst 2955 Switch Alarms

This section describes how to configure the different alarms for the Catalyst 2955 switch.

Note The alarms described in this chapter are not available on the Catalyst 2950 switch.

For complete syntax and usage information for the commands used in this chapter, see the switch command reference for this release.

This chapter consists of these sections:

• Understanding Catalyst 2955 Switch Alarms, page 3-1

• Configuring Catalyst 2955 Switch Alarms, page 3-4

• Displaying Catalyst 2955 Switch Alarms Status, page 3-11

Understanding Catalyst 2955 Switch Alarms

The Catalyst 2955 switch software monitors switch conditions on a per port or a switch basis. If the conditions present on the switch or port do not match the parameters set by the user, the switch software triggers an alarm or a system message. By default, the switch software sends the system messages to a system message logging facility, or a syslog facility. You can also configure the switch to send Simple Network Management Protocol (SNMP) traps to an SNMP server. You can configure the switch to trigger an external alarm device by using the two independent alarm relays (major or minor). For more information on how to configure the alarms, see the “Configuring Catalyst 2955 Switch Alarms” section

on page 3-4.

This section includes information about these topics:

• Global Status Monitoring Alarms, page 3-2

• FCS Error Hysteresis Threshold, page 3-2

• Port Status Monitoring Alarms, page 3-3

• Triggering Alarm Options, page 3-3

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Chapter 3 Configuring Catalyst 2955 Switch Alarms

Understanding Catalyst 2955 Switch Alarms

Global Status Monitoring Alarms

The Catalyst 2955 switch contains facilities for processing alarms related to temperature and power supply conditions. These are referred to as global or facility alarms. Tab le 3-1 lists the three global alarms and their descriptions and functions.

Table 3-1 Catalyst 2955 Global Status Monitoring Alarms

Alarm Description

Power Supply Alarm The switch monitors dual DC power supply levels. If the system is configured to operate in a dual

power mode, an alarm triggers if a power supply fails or is missing. The alarm is automatically cleared when both power supplies are present or working. You can configure the power supply alarm to be connected to the hardware relays. For more information, see the “Configuring the

Power Supply Alarm” section on page 3-5.

Temperature Alarms The switch contains a temperature sensor that monitors the environmental conditions inside the

switch. The switch contains two alarms that are associated with temperature.

• The primary alarm is enabled automatically to trigger both at a low temperature (-20

high temperature (95

C) for the safe operation of the switch. It cannot be changed or disabled.

By default, the primary temperature alarm is associated with the major relay.

• You can use the secondary temperature alarm to trigger an alarm when the system temperature

is greater than the configured temperature threshold. The lower threshold is configurable within the range of 40

C to the maximum threshold, 95oC. The secondary alarm is disabled by

default.

C) and a

For more information, see the “Configuring the Switch Temperature Alarms” section on page 3-6.

FCS Error Hysteresis Threshold

The Ethernet standard calls for a maximum bit error rate of 10-8. In the Catalyst 2955 switch, the bit error rate configurable range is from 10 If you want to configure the bit error rate of 10 the FCS bit error rate is 10

You can set the FCS error hysteresis threshold to prevent the toggle of the alarm when the actual bit error rate fluctuates near the configured bit error rate. The hysteresis threshold is defined as the ratio between the alarm clear threshold to the alarm set threshold, expressed as a percentage value.

For example, if the FCS bit error rate alarm value is configured to 10 threshold. To set the alarm clear threshold at 5*10

h = alarm clear threshold / alarm set threshold

h = 5*10

The FCS hysteresis threshold is applied to all ports on the Catalyst 2955 switch. The allowable range is from 1 to 10 percent. The default value is 10 percent. See the “Configuring the FCS Bit Error Rate

Alarm” section on page 3-7 for more information.

-10

/ 10-8 = 5*10-2 = 0.05 = 5 percent

-6

-11

to 10

-8

. The bit error rate input to the switch is a positive exponent.

-9

, then you enter the value 9 for the exponent. By default,

–8

-10

, the hysteresis, value h, is determined as follows:

, that value is the alarm set

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Chapter 3 Configuring Catalyst 2955 Switch Alarms

Port Status Monitoring Alarms

The Catalyst 2955 switch can also monitor the status of the Ethernet ports and generate alarm messages based on the alarms listed in Table 3-2. To save user time and effort, the switch supports changing alarm configurations by using alarm profiles. You can create a number of profiles and assign one of these profiles to each Ethernet port.

Alarm profiles provide a mechanism for you to enable or disable alarm conditions for a port and associate the alarm conditions with one or both alarm relays. You can also use alarm profiles to set alarm conditions to send alarm traps to an SNMP server and system messages to a syslog server. The alarm profile defaultPort is applied to all interfaces in the factory configuration (by default).

Note You can associate multiple alarms to one relay or one alarm to both relays.

Table 3-2 lists the port status monitoring alarms and their descriptions and functions. Each fault

condition is assigned a severity level based on the Cisco IOS System Error Message Severity Level.

Table 3-2 Catalyst 2955 Port Status Monitoring Alarms

Understanding Catalyst 2955 Switch Alarms

Alarm Description

Link Fault alarm The Catalyst 2955 switch generates a link fault alarm when there are problems with a port

physical layer that cause unreliable data transmission. A typical link fault condition is loss of signal or clock. The link fault alarm is cleared automatically when the link fault condition is cleared. The severity for this alarm is error condition, level 3.

Port not Forwarding alarm The switch generates a port not forwarding alarm when a port is not forwarding packets. This

alarm is cleared automatically when the port begins to forward packets. The severity for this alarm is warning, level 4.

Port is not Operating alarm The switch generates a port is not operating alarm when it finds that a port is in a failed state

during the startup self-test. When triggered, the port is not operating alarm is only cleared when the switch is restarted and the port is found to be operational. The severity for this alarm is error condition, level 3.

FCS Bit Error Rate alarm The switch generates an FCS Bit Error Rate alarm when the actual FCS Bit Error Rate is close

to the configured FCS Bit Error Rate. You can set the FCS bit error rate by using the interface configuration CLI for each of the ports. See the “Configuring the FCS Bit Error Rate Alarm”

section on page 3-7 for more information. The severity for this alarm is error condition, level

Triggering Alarm Options

The switch supports three methods for triggering alarms:

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• Configurable Relays

The switch is equipped with two independent alarm relays that can be triggered by alarms for global and port status conditions. The relays can be configured to send a fault signal to an external alarm device, such as a bell, light, or other signaling device. You can associate any alarm condition with either alarm relay or both relays. Each fault condition is assigned a severity level based on the Cisco IOS System Error Message Severity Level.

See the “Configuring Catalyst 2955 Switch Alarms” section on page 3-4 for more information on configuring the relays.

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Configuring Catalyst 2955 Switch Alarms

• SNMP Traps

SNMP is an application-layer protocol that provides a message format for communication between managers and agents. The SNMP system consists of an SNMP manager, an SNMP agent, and a management information base (MIB).

The snmp-server enable traps command can be modified in the Catalyst 2955 switch software to allow the user to send alarm traps to an SNMP server. You can use alarm profiles to set environmental or port status alarm conditions to send SNMP alarm traps. See the “Enabling SNMP

Traps” section on page 3-11 for more information.

• Syslog Messages

You can use alarm profiles to send system messages to a syslog server. See the “Configuring

Catalyst 2955 Switch Alarms” section on page 3-4 for more information.

Configuring Catalyst 2955 Switch Alarms

This section describes how to configure the Catalyst 2955 switch alarms:

• Default Catalyst 2955 Switch Alarm Configuration, page 3-4

• Configuring the Power Supply Alarm, page 3-5

Chapter 3 Configuring Catalyst 2955 Switch Alarms

• Configuring the Switch Temperature Alarms, page 3-6

• Configuring the FCS Bit Error Rate Alarm, page 3-7

• Configuring Alarm Profiles, page 3-9

• Enabling SNMP Traps, page 3-11

Default Catalyst 2955 Switch Alarm Configuration

Table 3-3 shows the default Catalyst 2955 switch alarms configuration.

Table 3-3 Default Catalyst 2955 Switch Alarm Configuration

Alarm Default Setting

Global Power Supply Alarm Enabled in switch single power mode. No alarm.

In dual power supply mode, the default alarm notification is a system message to the console.

Primary Temperature Alarm Enabled for switch temperature range 95

The primary switch temperature alarm is associated with the major relay.

Secondary Temperature Alarm Disabled.

Port Link Fault Alarm Disabled on all interfaces.

Port not Forwarding Alarm Disabled on all interfaces.

Port is not Operating Alarm Enabled on all interfaces.

FCS Bit Error Rate Alarm Disabled on all interfaces.

C maximum to -20oC minimum.

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Chapter 3 Configuring Catalyst 2955 Switch Alarms

Configuring the Power Supply Alarm

This section describes how to configure the power supply alarm on your switch. It contains this configuration information:

• Setting the Power Mode, page 3-5

• Setting the Power Supply Alarm Options, page 3-5

Setting the Power Mode

The Catalyst 2955 switch has two DC power inputs. By default, the system operates in the single power mode. You can use the power-supply dual global configuration command to set the dual mode operation. In dual-power mode, a second power supply gives power to the switch if the primary power supply fails.

Beginning in privileged EXEC mode, follow these steps to set the switch to dual power mode operation:

Command Purpose

Step 1

Step 2

Step 3

Step 4

Step 5

configure terminal Enter global configuration mode.

power-supply dual Set the system to dual mode operation.

end Return to privileged EXEC mode.

show alarm settings Verify the configuration.

copy running-config startup-config (Optional) Save your entries in the configuration file.

Configuring Catalyst 2955 Switch Alarms

Use the no power-supply dual command to disable this alarm by setting the switch back to single power mode operation.

Setting the Power Supply Alarm Options

Use the alarm facility power-supply global configuration command to associate the power supply alarm to a relay. You can also configure all alarms and traps associated with the power supply alarm to be sent to syslog and the SNMP server.

Beginning in privileged EXEC mode, follow these steps to associate the power supply alarm to a relay:

Command Purpose

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Step 7

configure terminal Enter global configuration mode.

alarm facility power-supply relay

Associate the power supply alarm to the major or minor relay.

{major | minor}

alarm facility power-supply notifies Configure sending power supply alarm traps to an SNMP server.

alarm facility power-supply syslog Configure sending power supply alarm traps to a syslog server.

end Return to privileged EXEC mode.

show alarm settings Verify the configuration.

copy running-config startup-config (Optional) Save your entries in the configuration file.

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Configuring Catalyst 2955 Switch Alarms

To disable sending the alarm to a relay, to syslog, or to an SNMP server, use the no alarm facility power-supply relay, no alarm facility power-supply notifies, or no alarm facility power-supply syslog global configuration commands.

Note Before you can use the notifies command to send alarm traps to an SNMP server, you must first set up

the SNMP server by using the snmp-server enable traps alarms global configuration command. See the “Enabling SNMP Traps” section on page 3-11.

This example sets the power-supply monitoring alarm to the minor relay.

Switch(config) # alarm facility power-supply relay minor

Configuring the Switch Temperature Alarms

The temperature thresholds for the primary temperature alarm cannot be changed, but you can change the association of the primary temperature alarm from the major relay to the minor relay. You can also set a lower maximum temperature threshold for the secondary temperature alarm and associate the alarm with either the major or minor relay.

Chapter 3 Configuring Catalyst 2955 Switch Alarms

This section describes how to configure the temperature alarms on your switch. It contains this configuration information:

• Setting a Secondary Temperature Threshold for the Switch, page 3-6

• Associating the Temperature Alarms to a Relay, page 3-7

Setting a Secondary Temperature Threshold for the Switch

In global configuration mode, you can use the alarm facility temperature secondary command to set a lower temperature threshold for the secondary temperature monitoring alarm. You can also use the alarm facility temperature secondary command to associate the secondary temperature alarm to either the major or minor alarm relay.

Beginning in privileged EXEC mode, follow these steps to set a lower temperature threshold:

Command Purpose

Step 1

Step 2

Step 3

Step 4

Step 5

configure terminal Enter global configuration mode.

alarm facility temperature secondary threshold

Set the secondary temperature threshold value. Enter values from 40 to 95 to set threshold from 40

C to 95oC.

end Return to privileged EXEC mode.

show alarm settings Verify the configuration.

copy running-config startup-config (Optional) Save your entries in the configuration file.

3-6

Use the no alarm facility temperature secondary threshold global configuration command to disable the secondary temperature threshold alarm.

This example disables the secondary temperature alarm.

Switch(config) # no alarm facility temperature secondary 45

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Chapter 3 Configuring Catalyst 2955 Switch Alarms

Associating the Temperature Alarms to a Relay

By default, the primary temperature alarm is associated to the major relay. You can use the alarm facility temperature command to associate the primary temperature alarm to the minor relay, to an SNMP trap,

to a syslog message, or to associate the secondary temperature alarm to the major or minor relay, an SNMP trap, or a syslog message.

Beginning in privileged EXEC mode, follow these steps to associate the secondary temperature alarm to a relay:

Command Purpose

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Step 7

configure terminal Enter global configuration mode.

alarm facility temperature

Associate the primary or secondary temperature alarm to a relay

{primary | secondary} relay {major | minor}

alarm facility temperature {primary | secondary} notifies

alarm facility temperature {primary | secondary} syslog

Configure sending primary or secondary temperature alarm traps to an SNMP server.

Configure sending primary or secondary temperature alarm traps to a syslog server.

end Return to privileged EXEC mode.

show alarm settings Verify the configuration.

copy running-config startup-config (Optional) Save your entries in the configuration file.

Configuring Catalyst 2955 Switch Alarms

Note Before you can use the notifies command to send alarm traps to an SNMP server, you must first set up

the SNMP server by using the snmp-server enable traps alarms global configuration command. See the “Enabling SNMP Traps” section on page 3-11.

Use the no alarm facility temperature secondary to disable the secondary temperature alarm.

This example sets the secondary temperature alarm to the minor relay, with a lower high temperature threshold value of 45

C. All alarm and traps associated with this alarm will be sent to a syslog server

and an SNMP server.

Switch(config) # alarm facility temperature secondary 45 Switch(config) # alarm facility temperature secondary relay minor Switch(config) # alarm facility temperature secondary syslog Switch(config) # alarm facility temperature secondary notifies

This example sets the first (primary) temperature alarm to the major relay. All alarms and traps associated with this alarm will be sent to a syslog server.

Switch(config) # alarm facility temperature primary syslog Switch(config) # alarm facility temperature primary relay major

Configuring the FCS Bit Error Rate Alarm

This section describes how to configure the FCS bit error rate alarm on your switch:

• Setting the FCS Error Threshold, page 3-8

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• Setting the FCS Error Hysteresis Threshold, page 3-8

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Configuring Catalyst 2955 Switch Alarms

Setting the FCS Error Threshold

The switch generates an FCS bit error rate alarm when the actual FCS bit error rate is close to the configured FCS bit error rate. Use the fcs-threshold interface configuration command to set the FCS error threshold.

Beginning in privileged EXEC mode, follow these steps to set the bit error rate value for a port:

Command Purpose

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

configure terminal Enter global configuration mode.

interface interface-id Enter the interface to be configured, and enter interface configuration mode.

fcs-threshold value Set the FCS error rate.

end Return to privileged EXEC mode.

show fcs-threshold Verify the setting.

copy running-config startup-config (Optional) Save your entries in the configuration file.

Chapter 3 Configuring Catalyst 2955 Switch Alarms

For value, the range is 6 to 11 to set a maximum bit error rate of 10

By default, the FCS bit error rate is 10

-8

-6

to 10

-11

Use the no fcs-threshold interface configuration command to return to the default FCS threshold value.

This example shows how to set the FCS bit error rate for a port to 10

Switch# configure terminal Switch(config)# interface fastethernet0/1 Switch(config-if) # fcs-threshold 10

Setting the FCS Error Hysteresis Threshold

The hysteresis setting prevents the toggle of an alarm when the actual bit error rate fluctuates near the configured bit error rate. Use the alarm facility fcs-hysteresis global configuration command to set the FCS error hysteresis threshold.

Note The FCS hysteresis threshold is applied to all ports of a Catalyst 2955 switch.

Beginning in privileged EXEC mode, follow these steps to set the FCS error hysteresis threshold for a switch:

Command Purpose

Step 1

Step 2

Step 3

Step 4

Step 5

configure terminal Enter global configuration mode.

alarm facility fcs-hysteresis

percentage

Set the hysteresis percentage for the switch.

For percentage, the range is 1 to 10. The default value is 10 percent.

end Return to privileged EXEC mode.

show running config Verify the configuration.

copy running-config startup-config (Optional) Save your entries in the configuration file.

-10

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Chapter 3 Configuring Catalyst 2955 Switch Alarms

Use the no alarm facility fcs-hysteresis command to set the FCS error hysteresis threshold to its default value.

Note The show running config command displays any FCS error hysteresis that is not the default value.

This example shows how to set the FCS error hysteresis at 5 percent.

Switch(config) # alarm facility fcs-hysteresis 5

Configuring Alarm Profiles

This section describes how to configure alarm profiles on your switch. It contains this configuration information:

• Creating or Modifying an Alarm Profile, page 3-9

• Attaching an Alarm Profile to a Specific Port, page 3-10

Creating or Modifying an Alarm Profile

Configuring Catalyst 2955 Switch Alarms

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Step 7

Step 8

Step 9

You can use the alarm profile global configuration command to create an alarm profile or to modify an existing profile. When you create a new alarm profile, none of the alarms are enabled.

Note The only alarm enabled in the defaultPort profile is the Port is not Operating alarm.

Beginning in privileged EXEC mode, follow these steps to create an alarm profile:

Command Purpose

configure terminal Enter global configuration mode.

alarm profile name Create the new profile or identify an existing profile, and then enter alarm

profile configuration mode.

alarm alarm-id Add or modify alarm parameters for a specific alarm (see Table 3-4). The

values are 1 to 4. You an enter more than one alarm ID separated by a space.

notifies alarm-id (Optional) Configure the alarm to send an SNMP trap to an SNMP server.

relay-major alarm-id relay-minor alarm-id

(Optional) Configure the alarm to send an alarm trap to the major relay.

(Optional) Configure the alarm to send an alarm trap to the minor relay.

syslog alarm-id (Optional) Configure the alarm to send an alarm trap to a syslog server.

end Return to privileged EXEC mode.

show alarm profile name Verify the configuration.

copy running-config startup-config (Optional) Save your entries in the configuration file.

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To delete an alarm profile, use the no alarm profile name global configuration command.

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Configuring Catalyst 2955 Switch Alarms

This example creates or modifies the alarm profile fastE for the fastEthernetPort with link-down (alarmList ID 3) and an FCS error rate of 30 percent (alarmList ID 4) alarms enabled. The link-down alarm is connected to the minor relay, and the FCS error rate alarm is connected to the major relay. These alarms also send notifications to an SNMP server and send system messages to a syslog server.

Switch(config)# alarm profile fastE Switch(config-alarm- prof)# alarm 3 4 Switch(config-alarm- prof)# relay major 4 Switch(config-alarm- prof)# relay minor 3 Switch(config-alarm- prof)# notifies 3 4 Switch(config-alarm- prof)# syslog 3 4

Note Before you can use the notifies command to send alarm traps to an SNMP server, you must first set up

the SNMP server by using the snmp-server enable traps alarms global configuration command. See the “Enabling SNMP Traps” section on page 3-11.

Table 3-4 lists the alarmList IDs and their corresponding alarm definitions. For a description of these

alarms, see the “Port Status Monitoring Alarms” section on page 3-3.

Table 3-4 AlarmList ID Number Alarm Descriptions

Chapter 3 Configuring Catalyst 2955 Switch Alarms

AlarmList ID Alarm Description

1 Link fault

2 Port not forwarding

3 Port not operating

4 FCS error rate exceeds threshold

Attaching an Alarm Profile to a Specific Port

In interface configuration mode, you can use the alarm-profile command to attach an alarm profile to a specific port.

Beginning in privileged EXEC mode, follow these steps to attach an alarm profile to a port:

Command Purpose

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

configure terminal Enter global configuration mode.

interface port interface Enter the number of the switch port to be configured, and the switch enters

interface configuration mode.

alarm-profile name Attach the specified profile to the interface.

end Return to privileged EXEC mode.

show alarm profile Verify the configuration.

copy running-config startup-config (Optional) Save your entries in the configuration file.

3-10

To detach an alarm profile from a specific port, use the no alarm-profile name interface configuration command.

This example attaches an alarm profile named fastE to a port.

Switch(config)# interface fastethernet 0/2 Switch(config-if)# alarm profile fastE

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Chapter 3 Configuring Catalyst 2955 Switch Alarms

This example detaches an alarm profile named fastE from a port.

Switch(config)# interface FastEthernet 0/2 Switch(config-if)# no alarm profile fastE

Enabling SNMP Traps

Use the snmp-server enable traps alarms global configuration command to enable the switch to send alarm traps.

Note Before using alarm profiles to set the switch to send SNMP alarm trap notifications to an SNMP server,

you must first enable SNMP by using the snmp-server enable traps alarms global configuration command.

Beginning in privileged EXEC mode, follow these steps to enable the switch to send alarm traps:

Command Purpose

Step 1

Step 2

Step 3

Step 4

Step 5

configure terminal Enter global configuration mode.

snmp-server enable traps alarms Enable the switch to send SNMP traps.

end Return to privileged EXEC mode.

show alarm settings Verify the configuration.

copy running-config startup-config (Optional) Save your entries in the configuration file.

Displaying Catalyst 2955 Switch Alarms Status

To display the global and port alarm status, use one or more of the privileged EXEC commands in

Table 3-5:

Table 3-5 Commands for Displaying Global and Port Alarm Status

Command Purpose

show alarm description port Displays an alarm number and its text description.

show alarm profile [name] Displays all alarm profiles in the system or a specified profile.

show alarm settings Displays all global alarm settings in the switch.

show env {all | power | temperature} Displays the status of environmental facilities on the Catalyst 2955 switch.

show alarm status [critical | info | major | minor]

Displays generated alarms in the switch.

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Displaying Catalyst 2955 Switch Alarms Status

Chapter 3 Configuring Catalyst 2955 Switch Alarms

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CHAPTER

Assigning the Switch IP Address and Default Gateway

This chapter describes how to create the initial switch configuration (for example, assign the switch IP address and default gateway information) for the Catalyst 2950 or Catalyst 2955 switch by using a variety of automatic and manual methods. It also describes how to modify the switch startup configuration only on the Catalyst 2950 Long-Reach Ethernet (LRE) switches.

Note For complete syntax and usage information for the commands used in this chapter, see the command

reference for this release and the Cisco IOS IP and IP Routing Command Reference, Release 12.1.

This chapter consists of these sections:

• Understanding the Boot Process, page 4-1

• Assigning Switch Information, page 4-2

• Checking and Saving the Running Configuration, page 4-11

• Modifying the Startup Configuration, page 4-11 (available only on the Catalyst 2950 LRE switch)

• Scheduling a Reload of the Software Image, page 4-16 (available only on the Catalyst 2950 LRE

switch)

Understanding the Boot Process

To start your switch, you need to follow the procedures in the hardware installation guide about installing and powering on the switch, and setting up the initial configuration (IP address, subnet mask, default gateway, secret and Telnet passwords, and so forth) of the switch.

The normal boot process involves the operation of the boot loader software, which performs these activities:

• Performs low-level CPU initialization. It initializes the CPU registers, which control where physical

memory is mapped, its quantity, its speed, and so forth.

• Performs power-on self-test (POST) for the CPU subsystem. It tests the CPU DRAM and the portion

of the flash device that makes up the flash file system.

• Initializes the flash file system on the system board.

• Loads a default operating system software image into memory and boots the switch.

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Assigning Switch Information

The boot loader provides access to the flash file system before the operating system is loaded. Normally, the boot loader is used only to load, uncompress, and launch the operating system. After the boot loader gives the operating system control of the CPU, the boot loader is not active until the next system reset or power on.

The boot loader also provides trap-door access into the system if the operating system has problems so serious that it cannot be used. The trap-door mechanism provides enough access to the system so that if it is necessary, you can format the flash file system, re-install the operating system software image by using the XMODEM Protocol, recover from a lost or forgotten password, and finally restart the operating system. For more information, see the “Recovering from a Software Failure” section on page 31-2, the

“Recovering from Lost or Forgotten Passwords on Non-LRE Catalyst 2950 Switches” section on page 31-2, the “Recovering from Lost or Forgotten Passwords on Catalyst 2950 LRE Switches” section on page 31-4, and the “Recovering from Lost or Forgotten Passwords on Catalyst 2955 Switches” section on page 31-8.

Before you can assign switch information, make sure you have connected a PC or terminal to the console port, and configured the PC or terminal-emulation software baud rate and character format to match these of the switch console port:

• Baud rate default is 9600.

• Data bits default is 8.

Chapter 4 Assigning the Switch IP Address and Default Gateway

• Stop bits default is 1.

• Parity settings default is none.

Note If you are using Express Setup, do not connect any devices to the switch before starting Express Setup.

See your switch hardware installation guide for more information.

Note The Catalyst 2955 switches do not support Express Setup.

Assigning Switch Information

You can assign IP information through the switch Express Setup program, through the command-line-interface (CLI)-based setup program, through a DHCP server, or manually by using the CLI. If you are an experienced user familiar with the switch configuration steps, manually configure the switch. Otherwise, use one of the setup programs.

Note The Catalyst 2955 switches do not support Express Setup.

Non-LRE Catalyst 2950 switches running a release prior to Cisco IOS Release 12.1(14)EA1 and Catalyst 2950 LRE switches running a release prior to Cisco IOS Release 12.1(19)EA1 do not support Express Setup.

4-2

Use the switch Express Setup or CLI-based setup program if you want to be prompted for specific IP information. With these programs, you can also configure a default gateway, a host name, and a switch (enable secret) password. You also have the option of assigning a Telnet password (to provide security during remote management) and enabling Simple Network Management Protocol (SNMP). The

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Chapter 4 Assigning the Switch IP Address and Default Gateway

CLI-based setup program also allows you to configure your switch as a command or member switch of a cluster or as a standalone switch. For more information about the Express Setup and CLI-based setup programs, see the hardware installation guide for your switch.

Use a DHCP server for centralized control and automatic assignment of IP information after the server is configured.

Note If you are using DHCP, do not respond to any of the questions in the setup program until the switch

receives the dynamically assigned IP address and reads the configuration file.

This section has this configuration information:

• Default Switch Information, page 4-3

• Understanding DHCP-Based Autoconfiguration, page 4-3

• Configuring DHCP-Based Autoconfiguration, page 4-5

• Manually Assigning IP Information, page 4-10

Assigning Switch Information

Default Switch Information

Table 4-1 shows the default switch information.

Table 4-1 Default Switch Information

Feature Default Setting

IP address and subnet mask No IP address or subnet mask are defined.

Default gateway No default gateway is defined.

Enable secret password No password is defined.

Hostname The factory-assigned default host name is Switch.

Telnet password No password is defined.

Cluster command switch functionality Disabled.

Cluster name No cluster name is defined.

Understanding DHCP-Based Autoconfiguration

DHCP provides configuration information to Internet hosts and internetworking devices. This protocol consists of two components: one for delivering configuration parameters from a DHCP server to a device and a mechanism for allocating network addresses to devices. DHCP is built on a client-server model, in which designated DHCP servers allocate network addresses and deliver configuration parameters to dynamically configured devices. The switch can act as both a DHCP client and a DHCP server.

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Note The DHCP server feature is only available on Catalyst 2955 switches.

During DHCP-based autoconfiguration, your switch (DHCP client) is automatically configured at startup with IP address information and a configuration file.

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Assigning Switch Information

With DHCP-based autoconfiguration, no DHCP client-side configuration is needed on your switch. However, you need to configure the DHCP server for various lease options associated with IP addresses. If you are using DHCP to relay the configuration file location on the network, you might also need to configure a TFTP server and a Domain Name System (DNS) server.

The DHCP server for your switch can be on the same LAN or on a different LAN than the switch. If the DHCP server is running on a different LAN, you should configure a DHCP relay device between your switch and the DHCP server. A relay device forwards broadcast traffic between two directly connected LANs. A router does not forward broadcast packets, but it forwards packets based on the destination IP address in the received packet.

DHCP-based autoconfiguration replaces the BOOTP client functionality on your switch.

DHCP Client Request Process

When you boot your switch, the DHCP client is invoked and requests configuration information from a DHCP server when the configuration file is not present on the switch.

DHCP autoconfiguration does not occur under these conditions:

• When a configuration file is present and the service config global configuration command is

disabled on the switch.

Chapter 4 Assigning the Switch IP Address and Default Gateway

• When a configuration file is present and the service config global configuration command is enabled

on the switch. In this case, the switch broadcasts TFTP requests for the configuration file.

Figure 4-1 shows the sequence of messages that are exchanged between the DHCP client and the DHCP

server.

Figure 4-1 DHCP Client and Server Message Exchange

DHCPDISCOVER (broadcast)

Switch A

DHCPOFFER (unicast)

DHCPREQUEST (broadcast)

DHCPACK (unicast)

DHCP server

51807

The client, Switch A, broadcasts a DHCPDISCOVER message to locate a DHCP server. The DHCP server offers configuration parameters (such as an IP address, subnet mask, gateway IP address, DNS IP address, a lease for the IP address, and so forth) to the client in a DHCPOFFER unicast message.

In a DHCPREQUEST broadcast message, the client returns a formal request for the offered configuration information to the DHCP server. The formal request is broadcast so that all other DHCP servers that received the DHCPDISCOVER broadcast message from the client can reclaim the IP addresses that they offered to the client.

The DHCP server confirms that the IP address has been allocated to the client by returning a DHCPACK unicast message to the client. With this message, the client and server are bound, and the client uses configuration information received from the server. The amount of information the switch receives depends on how you configure the DHCP server. For more information, see the “DHCP Server

Configuration Guidelines” section on page 4-5.

4-4

If the configuration parameters sent to the client in the DHCPOFFER unicast message are invalid (a configuration error exists), the client returns a DHCPDECLINE broadcast message to the DHCP server.

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The DHCP server sends the client a DHCPNAK denial broadcast message, which means that the offered configuration parameters have not been assigned, that an error has occurred during the negotiation of the parameters, or that the client has been slow in responding to the DHCPOFFER message (the DHCP server assigned the parameters to another client).

A DHCP client might receive offers from multiple DHCP or BOOTP servers and can accept any of the offers; however, the client usually accepts the first offer it receives. The offer from the DHCP server is not a guarantee that the IP address is allocated to the client; however, the server usually reserves the address until the client has had a chance to formally request the address. If the switch accepts replies from a BOOTP server and configures itself, the switch broadcasts, instead of unicasts, TFTP requests to obtain the switch configuration file.

Configuring DHCP-Based Autoconfiguration

These sections describe how to configure DHCP-based autoconfiguration.

• DHCP Server Configuration Guidelines, page 4-5

• Configuring the TFTP Server, page 4-6

• Configuring the DNS, page 4-6

Assigning Switch Information

• Configuring the Relay Device, page 4-7

• Obtaining Configuration Files, page 4-8

• Example Configuration, page 4-9

If your DHCP server is a Cisco device, or if you are configuring the switch as a DHCP server, see the “IP Addressing and Services” section in the Cisco IOS IP and IP Routing Configuration Guide for Cisco IOS Release 12.1 for additional information about configuring DHCP.

DHCP Server Configuration Guidelines

Follow these guidelines if you are configuring a device as a DHCP server:

The switch can act as both the DHCP client and the DHCP server. By default, the Cisco IOS DHCP server and relay agent features are enabled on your switch.

Note The DHCP server feature is only available on Catalyst 2955 switches.

You should configure the DHCP server with reserved leases that are bound to each switch by the switch hardware address.

If you want the switch to receive IP address information, you must configure the DHCP server with these lease options:

• IP address of the client (required)

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• Subnet mask of the client (required)

• DNS server IP address (optional)

• Router IP address (default gateway address to be used by the switch) (required)

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Assigning Switch Information

If you want the switch to receive the configuration file from a TFTP server, you must configure the DHCP server with these lease options:

• TFTP server name (required)

• Boot filename (the name of the configuration file that the client needs) (recommended)

• Host name (optional)

Depending on the settings of the DHCP server, the switch can receive IP address information, the configuration file, or both.

If you do not configure the DHCP server with the lease options described previously, it replies to client requests with only those parameters that are configured. If the IP address and subnet mask are not in the reply, the switch is not configured. If the router IP address or TFTP server name are not found, the switch might send broadcast, instead of unicast, TFTP requests. Unavailability of other lease options does not affect autoconfiguration.

Configuring the TFTP Server

Based on the DHCP server configuration, the switch attempts to download one or more configuration files from the TFTP server. If you configured the DHCP server to respond to the switch with all the options required for IP connectivity to the TFTP server, and if you configured the DHCP server with a TFTP server name, address, and configuration filename, the switch attempts to download the specified configuration file from the specified TFTP server.

Chapter 4 Assigning the Switch IP Address and Default Gateway

If you did not specify the configuration filename, the TFTP server, or if the configuration file could not be downloaded, the switch attempts to download a configuration file by using various combinations of filenames and TFTP server addresses. The files include the specified configuration filename (if any) and these files: network-config, cisconet.cfg, hostname.config, or hostname.cfg, where hostname is the switch’s current hostname. The TFTP server addresses used include the specified TFTP server address (if any) and the broadcast address (255.255.255.255).

For the switch to successfully download a configuration file, the TFTP server must contain one or more configuration files in its base directory. The files can include these files:

• The configuration file named in the DHCP reply (the actual switch configuration file).

• The network-confg or the cisconet.cfg file (known as the default configuration files).

• The router-confg or the ciscortr.cfg file (These files contain commands common to all switches.

If you specify the TFTP server name in the DHCP server-lease database, you must also configure the TFTP server name-to-IP-address mapping in the DNS-server database.

If the TFTP server to be used is on a different LAN from the switch, or if it is to be accessed by the switch through the broadcast address (which occurs if the DHCP server response does not contain all the required information described previously), a relay must be configured to forward the TFTP packets to the TFTP server. For more information, see the “Configuring the Relay Device” section on page 4-7. The preferred solution is to configure the DHCP server with all the required information.

Configuring the DNS

Normally, if the DHCP and TFTP servers are properly configured, these files are not accessed.)

4-6

The DHCP server uses the DNS server to resolve the TFTP server name to an IP address. You must configure the TFTP server name-to-IP address map on the DNS server. The TFTP server contains the configuration files for the switch.

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You can configure the IP addresses of the DNS servers in the lease database of the DHCP server from where the DHCP replies will retrieve them. You can enter up to two DNS server IP addresses in the lease database.

The DNS server can be on the same or on a different LAN as the switch. If it is on a different LAN, the switch must be able to access it through a router.

Configuring the Relay Device

You must configure a relay device, also referred to an a relay agent, when a switch sends broadcast packets that require a response from a host on a different LAN. Examples of broadcast packets that the switch might send are DHCP, DNS, and in some cases, TFTP packets. You must configure this relay device to forward received broadcast packets on an interface to the destination host.

If the relay device is a Cisco router, enable IP routing (ip routing global configuration command), and configure helper addresses by using the ip helper-address interface configuration command.

For example, in Figure 4-2, configure the router interfaces as follows:

On interface 10.0.0.2:

router(config-if)# ip helper-address 20.0.0.2 router(config-if)# ip helper-address 20.0.0.3 router(config-if)# ip helper-address 20.0.0.4

Assigning Switch Information

On interface 20.0.0.1

router(config-if)# ip helper-address 10.0.0.1

Figure 4-2 Relay Device Used in Autoconfiguration

Switch

(DHCP client)

10.0.0.1

20.0.0.2 20.0.0.3

DHCP server TFTP server DNS server

Cisco router

(Relay)

10.0.0.2

20.0.0.1

20.0.0.4

49068

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Assigning Switch Information

Obtaining Configuration Files

Depending on the availability of the IP address and the configuration filename in the DHCP reserved lease, the switch obtains its configuration information in these ways:

• The IP address and the configuration filename is reserved for the switch and provided in the DHCP

reply (one-file read method).

The switch receives its IP address, subnet mask, TFTP server address, and the configuration filename from the DHCP server. The switch sends a unicast message to the TFTP server to retrieve the named configuration file from the base directory of the server, and upon receipt, it completes its boot-up process.

• The IP address and the configuration filename is reserved for the switch, but the TFTP server

address is not provided in the DHCP reply (one-file read method).

The switch receives its IP address, subnet mask, and the configuration filename from the DHCP server. The switch sends a broadcast message to a TFTP server to retrieve the named configuration file from the base directory of the server, and upon receipt, it completes its boot-up process.

• Only the IP address is reserved for the switch and provided in the DHCP reply. The configuration

filename is not provided (two-file read method).

Chapter 4 Assigning the Switch IP Address and Default Gateway

The switch receives its IP address, subnet mask, and the TFTP server address from the DHCP server. The switch sends a unicast message to the TFTP server to retrieve the network-confg or cisconet.cfg default configuration file. (If the network-confg file cannot be read, the switch reads the cisconet.cfg file.)

The default configuration file contains the host names-to-IP-address mapping for the switch. The switch fills its host table with the information in the file and obtains its host name. If the host name is not found in the file, the switch uses the host name in the DHCP reply. If the host name is not specified in the DHCP reply, the switch uses the default Switch as its host name.

After obtaining its host name from the default configuration file or the DHCP reply, the switch reads the configuration file that has the same name as its host name (hostname-confg or hostname.cfg, depending on whether network-confg or cisconet.cfg was read earlier) from the TFTP server. If the cisconet.cfg file is read, the filename of the host is truncated to eight characters.

If the switch cannot read the network-confg, cisconet.cfg, or the hostname file, it reads the router-confg file. If the switch cannot read the router-confg file, it reads the ciscortr.cfg file.

Note The switch broadcasts TFTP server requests if the TFTP server is not obtained from the DHCP replies,

if all attempts to read the configuration file through unicast transmissions fail, or if the TFTP server name cannot be resolved to an IP address.

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Example Configuration

Figure 4-3 shows a sample network for retrieving IP information by using DHCP-based autoconfiguration.

Figure 4-3 DHCP-Based Autoconfiguration Network Example

Assigning Switch Information

Switch 1

00e0.9f1e.2001

Cisco router

10.0.0.10

DHCP server DNS server TFTP server

Switch 2

00e0.9f1e.2002

10.0.0.1

Switch 3

00e0.9f1e.2003

10.0.0.2 10.0.0.3

(tftpserver)

Switch 4

00e0.9f1e.2004

111394

Table 4-2 shows the configuration of the reserved leases on the DHCP server.

Table 4-2 DHCP Server Configuration

Switch-1 Switch-2 Switch-3 Switch-4

Binding key

00e0.9f1e.2001 00e0.9f1e.2002 00e0.9f1e.2003 00e0.9f1e.2004

(hardware address)

IP address 10.0.0.21 10.0.0.22 10.0.0.23 10.0.0.24

Subnet mask 255.255.255.0 255.255.255.0 255.255.255.0 255.255.255.0

Router address 10.0.0.10 10.0.0.10 10.0.0.10 10.0.0.10

DNS server address 10.0.0.2 10.0.0.2 10.0.0.2 10.0.0.2

TFTP server name tftpserver or 10.0.0.3 tftpserver or 10.0.0.3 tftpserver or 10.0.0.3 tftpserver or 10.0.0.3

Boot filename

switcha-confg switchb-confg switchc-confg switchd-confg (configuration file) (optional)

Host name (optional) switcha switchb switchc switchd

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DNS Server Configuration

The DNS server maps the TFTP server name tftpserver to IP address 10.0.0.3.

TFTP Server Configuration (on UNIX)

The TFTP server base directory is set to /tftpserver/work/. This directory contains the network-confg file used in the two-file read method. This file contains the host name to be assigned to the switch based on its IP address. The base directory also contains a configuration file for each switch (switcha-confg, switchb-confg, and so forth) as shown in this display:

prompt> cd /tftpserver/work/ prompt> ls network-confg switcha-confg

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Assigning Switch Information

switchb-confg switchc-confg switchd-confg prompt> cat network-confg ip host switch1 10.0.0.21 ip host switch2 10.0.0.22 ip host switch3 10.0.0.23 ip host switch4 10.0.0.24

DHCP Client Configuration

No configuration file is present on Switch A through Switch D.

Configuration Explanation

In Figure 4-3, Switch A reads its configuration file as follows:

• It obtains its IP address 10.0.0.21 from the DHCP server.

• If no configuration filename is given in the DHCP server reply, Switch A reads the network-confg

file from the base directory of the TFTP server.

• It adds the contents of the network-confg file to its host table.

• It reads its host table by indexing its IP address 10.0.0.21 to its host name (switcha).

Chapter 4 Assigning the Switch IP Address and Default Gateway

• It reads the configuration file that corresponds to its host name; for example, it reads switch1-confg

from the TFTP server.

Switches B through D retrieve their configuration files and IP addresses in the same way.

Manually Assigning IP Information

Beginning in privileged EXEC mode, follow these steps to manually assign IP information to VLANs or ports:

Command Purpose

Step 1

Step 2

Step 3

Step 4

Step 5

configure terminal Enter global configuration mode.

interface vlan vlan-id Enter interface configuration mode, and enter the VLAN to which the IP

information is assigned. The range is 1 to 4094 when the enhanced software image is installed and 1 to 1001 when the standard software image is installed.

ip address ip-address subnet-mask Enter the IP address and subnet mask.

exit Return to global configuration mode.

ip default-gateway ip-address Enter the IP address of the next-hop router interface that is directly

connected to the switch where a default gateway is being configured. The default gateway receives IP packets with unresolved destination IP addresses from the switch.

Step 6

Step 7

4-10

Once the default gateway is configured, the switch has connectivity to the remote networks with which a host needs to communicate.

Note When your switch is configured to route with IP, it does not need

to have a default gateway set.

end Return to privileged EXEC mode.

show interfaces vlan vlan-id Verify the configured IP address.

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Checking and Saving the Running Configuration

Command Purpose

Step 8

Step 9

show ip redirects Verify the configured default gateway.

copy running-config startup-config (Optional) Save your entries in the configuration file.

To remove the switch IP address, use the no ip address interface configuration command. If you are removing the address through a Telnet session, your connection to the switch will be lost. To remove the default gateway address, use the no ip default-gateway global configuration command.

For information on setting the switch system name, protecting access to privileged EXEC commands, and setting time and calendar services, see Chapter 7, “Administering the Switch.”

Checking and Saving the Running Configuration

You can check the configuration settings you entered or changes you made by entering the show running-config privileged EXEC command: For information about the output of this command, see the

Cisco IOS Configuration Fundamental Command Reference for Release 12.1.

To store the configuration or changes you have made to your startup configuration in flash memory, enter the copy running-config startup-config privileged EXEC command. This command saves the configuration settings that you made. If you fail to do this, your configuration will be lost the next time you reload the system. To display information stored in the NVRAM section of flash memory, use the show startup-config or more startup-config privileged EXEC command.

For more information about alternative locations from which to copy the configuration file on the Catalyst 2950 LRE switches, see Appendix B, “Working with the Cisco IOS File System, Configuration

Files, and Software Images.”

Modifying the Startup Configuration

This section describes how to modify the switch startup configuration only on a Catalyst 2950 LRE switch. It contains this configuration information:

• Default Boot Configuration, page 4-12

• Automatically Downloading a Configuration File, page 4-12

• Specifying the Filename to Read and Write the System Configuration, page 4-12

• Booting Manually, page 4-13

• Booting a Specific Software Image, page 4-13

• Controlling Environment Variables, page 4-14

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Modifying the Startup Configuration

Default Boot Configuration

Table 4-3 shows the default boot configuration.

Table 4-3 Default Boot Configuration

Feature Default Setting

Operating system software image The switch attempts to automatically boot the system using information in the BOOT

environment variable. If the variable is not set, the switch attempts to load and execute the first executable image it can by performing a recursive, depth-first search throughout the flash file system.

The software image is stored in a directory that has the same name as the image file (excluding the .bin extension).

In a depth-first search of a directory, each encountered subdirectory is completely searched before continuing the search in the original directory.

Configuration file Configured switches use the config.text file stored on the system board in flash

memory.

A new switch has no configuration file.

Automatically Downloading a Configuration File

You can automatically download a configuration file to your switch by using the DHCP-based autoconfiguration feature. For more information, see the “Understanding DHCP-Based

Autoconfiguration” section on page 4-3.

Specifying the Filename to Read and Write the System Configuration

By default, the Cisco IOS software uses the file config.text to read and write a nonvolatile copy of the system configuration. However, you can specify a different filename that will be loaded during the next boot cycle.

Beginning in privileged EXEC mode, follow these steps to specify a different configuration filename:

Command Purpose

Step 1

Step 2

configure terminal Enter global configuration mode.

boot config-file flash:/file-url Specify the configuration file to load during the next boot cycle.

For file-url, specify the path (directory) and the configuration filename.

Step 3

Step 4

Step 5

4-12

Filenames and directory names are case sensitive.

end Return to privileged EXEC mode.

show boot Verify your entries.

The boot config-file global configuration command changes the setting of the CONFIG_FILE environment variable.

copy running-config startup-config (Optional) Save your entries in the configuration file.

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To return to the default setting, use the no boot config-file global configuration command.

Booting Manually

By default, the switch automatically boots; however, you can configure it to manually boot.

Beginning in privileged EXEC mode, follow these steps to configure the switch to manually boot during the next boot cycle:

Command Purpose

Step 1

Step 2

Step 3

Step 4

configure terminal Enter global configuration mode.

boot manual Enable the switch to manually boot during the next boot cycle.

end Return to privileged EXEC mode.

show boot Verify your entries.

Modifying the Startup Configuration

The boot manual global command changes the setting of the MANUAL_BOOT environment variable.

Step 5

copy running-config startup-config (Optional) Save your entries in the configuration file.

To disable manual booting, use the no boot manual global configuration command.

Booting a Specific Software Image

By default, the switch attempts to automatically boot the system using information in the BOOT environment variable. If this variable is not set, the switch attempts to load and execute the first executable image it can by performing a recursive, depth-first search throughout the flash file system. In a depth-first search of a directory, each encountered subdirectory is completely searched before continuing the search in the original directory. However, you can specify a specific image to boot.

The next time you reboot the system, the switch is in boot loader mode, shown by the switch: prompt. To boot the system, use the boot filesystem:/file-url boot loader command.

• For filesystem:, use flash: for the system board flash device.

• For file-url, specify the path (directory) and the name of the

bootable image.

Filenames and directory names are case sensitive.

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Modifying the Startup Configuration

Beginning in privileged EXEC mode, follow these steps to configure the switch to boot a specific image during the next boot cycle:

Command Purpose

Step 1

Step 2

Step 3

Step 4

configure terminal Enter global configuration mode.

boot system filesystem:/file-url Configure the switch to boot a specific image in flash memory during the

end Return to privileged EXEC mode.

show boot Verify your entries.

Chapter 4 Assigning the Switch IP Address and Default Gateway

next boot cycle.

• For filesystem:, use flash: for the system board flash device.

• For file-url, specify the path (directory) and the name of the bootable

image.

Filenames and directory names are case sensitive.

The boot system global command changes the setting of the BOOT environment variable.

During the next boot cycle, the switch attempts to automatically boot the system using information in the BOOT environment variable.

Step 5

copy running-config startup-config (Optional) Save your entries in the configuration file.

To return to the default setting, use the no boot system global configuration command.

Controlling Environment Variables

You enter the boot loader mode only through a switch console connection configured for 9600 bps. Unplug the switch power cord, and press the switch Mode button while reconnecting the power cord. Release the Mode button a second or two after the LED above port 1X turns off. Then the boot loader switch: prompt appears.

The switch boot loader software provides support for nonvolatile environment variables, which can be used to control how the boot loader, or any other software running on the system, behaves. Boot loader environment variables are similar to environment variables that can be set on UNIX or DOS systems.

Environment variables that have values are stored in the flash file system in various files as shown in

Table 4-4.

Table 4-4 Environment Variables Storage Location

Environment Variable Location (file system:filename)

BAUD, ENABLE_BREAK, CONFIG_BUFSIZE, CONFIG_FILE, MANUAL_BOOT, PS1

BOOT, BOOTHLPR, HELPER, HELPER_CONFIG_FILE flash:system_env_vars

flash:env_vars

4-14

Each line in these files contains an environment variable name and an equal sign followed by the value of the variable. A variable has no value if it is not listed in this file; it has a value if it is listed in the file even if the value is a null string. A variable that is set to a null string (for example, “ ”) is a variable with a value. Many environment variables are predefined and have default values.

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Modifying the Startup Configuration

Environment variables store two kinds of data:

• Data that controls code, which does not read the Cisco IOS configuration file. For example, the name

of a boot loader helper file, which extends or patches the functionality of the boot loader can be stored as an environment variable.

• Data that controls code, which is responsible for reading the Cisco IOS configuration file. For

example, the name of the Cisco IOS configuration file can be stored as an environment variable.

You can change the settings of the environment variables by accessing the boot loader or by using Cisco IOS commands. It is not necessary to alter the setting of the environment variables.

Note For complete syntax and usage information for the boot loader commands and environment variables,

see the command reference for this release.

Table 4-5 describes the function of the most common environment variables.

Table 4-5 Environment Variables

Variable Boot Loader Command Cisco IOS Global Configuration Command

MANUAL_BOOT set MANUAL_BOOT yes

boot manual

Decides whether the switch automatically or manually boots.

Valid values are 1, yes, 0, and no. If it is set to no or 0, the boot loader attempts to automatically boot the system. If it is set to anything else, you must manually boot the switch from the boot loader mode.

BOOT set BOOT filesystem:/file-url ...

A semicolon-separated list of executable files to try to load and execute when automatically booting. If the BOOT environment variable is not set, the system attempts to load and execute the first executable image it can find by using a recursive, depth-first search through the flash file system. If the BOOT variable is set but the specified images cannot be loaded, the system attempts to boot the first bootable file that it can find in the flash file system.

Enables manually booting the switch during the next boot cycle and changes the setting of the MANUAL_BOOT environment variable.

The next time you reboot the system, the switch is in boot loader mode. To boot the system, use the boot flash:filesystem:/file-url boot loader command, and specify the name of the bootable image.

boot system filesystem:/file-url

Specifies the software image to load during the next boot cycle. This command changes the setting of the BOOT environment variable.

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Scheduling a Reload of the Software Image

Table 4-5 Environment Variables (continued)

Variable Boot Loader Command Cisco IOS Global Configuration Command

CONFIG_FILE set CONFIG_FILE flash:/file-url

Changes the filename that the software uses to read and write a nonvolatile copy of the system configuration.

CONFIG_BUFSIZE set CONFIG_BUFSIZE size

Changes the buffer size that the software uses to hold a copy of the configuration file in memory. The configuration file cannot be larger than the buffer size allocation. The range is from 4096 to 524288 bytes.

boot config-file flash:/file-url

Specifies the filename that the software uses to read and write a nonvolatile copy of the system configuration. This command changes the CONFIG_FILE environment variable.

boot buffersize size

Specifies the size of the file system-simulated NVRAM in flash memory. The buffer holds a copy of the configuration file in memory. This command changes the setting of the CONFIG_BUFSIZE environment variable.

You must reload the switch by using the reload privileged EXEC command for this command to take effect.

Scheduling a Reload of the Software Image

You can schedule a reload of the software image to occur only an LRE switch at a later time (for example, late at night or during the weekend when the switch is used less), or you can synchronize a reload network-wide (for example, to perform a software upgrade on all switches in the network).

Note A scheduled reload must take place within approximately 24 days.

Configuring a Scheduled Reload

To configure your switch to reload the software image at a later time, use one of these commands in privileged EXEC mode:

• reload in [hh:]mm [text]

This command schedules a reload of the software to take affect in the specified minutes or hours and minutes. The reload must take place within approximately 24 days. You can specify the reason for the reload in a string up to 255 characters in length.

• reload at hh:mm [month day | day month] [text]

This command schedules a reload of the software to take place at the specified time (using a 24-hour clock). If you specify the month and day, the reload is scheduled to take place at the specified time and date. If you do not specify the month and day, the reload takes place at the specified time on the current day (if the specified time is later than the current time) or on the next day (if the specified time is earlier than the current time). Specifying 00:00 schedules the reload for midnight.

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Note Use the at keyword only if the switch system clock has been set (through Network Time

Protocol (NTP), the hardware calendar, or manually). The time is relative to the configured time zone on the switch. To schedule reloads across several switches to occur simultaneously, the time on each switch must be synchronized with NTP.

The reload command halts the system. If the system is not set to manually boot, it reboots itself. Use the

reload command after you save the switch configuration information to the startup configuration (copy running-config startup-config).

If your switch is configured for manual booting, do not reload it from a virtual terminal. This restriction prevents the switch from entering the boot loader mode and thereby taking it from the remote user’s control.

If you modify your configuration file, the switch prompts you to save the configuration before reloading. During the save operation, the system requests whether you want to proceed with the save if the CONFIG_FILE environment variable points to a startup configuration file that no longer exists. If you proceed in this situation, the system enters setup mode upon reload.

This example shows how to reload the software on the switch on the current day at 7:30 p.m:

Switch# reload at 19:30 Reload scheduled for 19:30:00 UTC Wed Jun 5 1996 (in 2 hours and 25 minutes) Proceed with reload? [confirm]

Scheduling a Reload of the Software Image

This example shows how to reload the software on the switch at a future time:

Switch# reload at 02:00 jun 20 Reload scheduled for 02:00:00 UTC Thu Jun 20 1996 (in 344 hours and 53 minutes) Proceed with reload? [confirm]

To cancel a previously scheduled reload, use the reload cancel privileged EXEC command.

Displaying Scheduled Reload Information

To display information about a previously scheduled reload or to determine if a reload has been scheduled on the switch, use the show reload privileged EXEC command.

It displays reload information including the time the reload is scheduled to occur and the reason for the reload (if it was specified when the reload was scheduled).

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Scheduling a Reload of the Software Image

Chapter 4 Assigning the Switch IP Address and Default Gateway

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CHAPTER

Configuring IE2100 CNS Agents

This chapter describes how to configure the Intelligence Engine 2100 (IE2100) Series Cisco Networking Services (CNS) embedded agents on your Catalyst 2950 or Catalyst 2955 switch. To use the feature described in this chapter, you must have the enhanced software image (EI) installed on your switch.

Note For complete syntax and usage information for the commands used in this section, see the Cisco

Intelligence Engine 2100 Series Configuration Registrar Manual, and select Cisco IOS Software

Release 12.2 > New Feature Documentation > 12.2(2)T on Cisco.com.

This chapter consists of these sections:

• Understanding IE2100 Series Configuration Registrar Software, page 5-1

• Understanding CNS Embedded Agents, page 5-5

• Configuring CNS Embedded Agents, page 5-6

• Displaying CNS Configuration, page 5-12

Understanding IE2100 Series Configuration Registrar Software

The IE2100 Series Configuration Registrar is a network management device that acts as a configuration service for automating the deployment and management of network devices and services (see Figure 5-1). Each Configuration Registrar manages a group of Cisco IOS devices (switches and routers) and the services that they deliver, storing their configurations and delivering them as needed. The Configuration Registrar automates initial configurations and configuration updates by generating device-specific configuration changes, sending them to the device, executing the configuration change, and logging the results.

The Configuration Registrar supports standalone and server modes and has these CNS components:

• Configuration service (web server, file manager, and namespace mapping server)

• Event service (event gateway)

• Data service directory (data models and schema)

In standalone mode, the Configuration Registrar supports an embedded CNS Directory Service. In this mode, no external directory or other data store is required. In server mode, the Configuration Registrar supports the use of a user-defined external directory.

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Understanding IE2100 Series Configuration Registrar Software

Figure 5-1 Configuration Registrar Architectural Overview

Service provider network

Chapter 5 Configuring IE2100 CNS Agents

Configuration

registrar

Data service directory

Configuration server

Event service

Web-based user interface

Order entry

configuration management

These sections contain this conceptual information:

• CNS Configuration Service, page 5-2

• CNS Event Service, page 5-3

• What You Should Know About ConfigID, DeviceID, and Host Name, page 5-3

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CNS Configuration Service

The CNS Configuration Service is the core component of the Configuration Registrar. It consists of a configuration server that works with CNS configuration agents located on the switch. The CNS Configuration Service delivers device and service configurations to the switch for initial configuration and mass reconfiguration by logical groups. Switches receive their initial configuration from the CNS Configuration Service when they start up on the network for the first time.

The CNS Configuration Service uses the CNS Event Service to send and receive configuration change events and to send success and failure notifications.

The configuration server is a web server that uses configuration templates and the device-specific configuration information stored in the embedded (standalone mode) or remote (server mode) directory.

Configuration templates are text files containing static configuration information in the form of CLI commands. In the templates, variables are specified using lightweight directory access protocol (LDAP) URLs that reference the device-specific configuration information stored in a directory.

The configuration agent can perform a syntax check on received configuration files and publish events to indicate the success or failure of the syntax check. The configuration agent can either apply configurations immediately or delay the application until receipt of a synchronization event from the configuration server.

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CISCO WS-C2950-12, Catalyst 2950 User Manual

Specifications and Main Features

Frequently Asked Questions

User Manual

CONTENTS

Audience

Purpose

Preface

Conventions

Related Publications

Obtaining Documentation

Cisco.com

Product Documentation DVD

Ordering Documentation

Documentation Feedback

Cisco Product Security Overview

Reporting Security Problems in Cisco Products

Obtaining Technical Assistance

Cisco Technical Support & Documentation Website

Submitting a Service Request

Obtaining Additional Publications and Information

Definitions of Service Request Severity

Features

Overview

Ease of Use and Ease of Deployment

Performance

Manageability

Redundancy

VLAN Support

Security

Quality of Service and Class of Service

Monitoring

LRE Features (available only on Catalyst 2950 LRE switches)

Management Options

Management Interface Options

Advantages of Using Network Assistant and Clustering Switches

Network Configuration Examples

Design Concepts for Using the Switch

Small to Medium-Sized Network Configuration

Collapsed Backbone and Switch Cluster Configuration

Hotel Network Configuration

Service-Provider Central-Office Configuration

Large Campus Configuration

Multidwelling Network Using Catalyst 2950 Switches

Where to Go Next

Long-Distance, High-Bandwidth Transport Configuration

Using the Command-Line Interface

Cisco IOS Command Modes

Getting Help

Abbreviating Commands

Using no and default Forms of Commands

Understanding CLI Messages

Using Command History

Changing the Command History Buffer Size

Using Editing Features

Recalling Commands

Disabling the Command History Feature

Enabling and Disabling Editing Features

Editing Commands through Keystrokes

Editing Command Lines that Wrap

Searching and Filtering Output of show and more Commands

Accessing the CLI

Configuring Catalyst 2955 Switch Alarms

Understanding Catalyst 2955 Switch Alarms

Global Status Monitoring Alarms

FCS Error Hysteresis Threshold

Port Status Monitoring Alarms

Triggering Alarm Options

Configuring the Power Supply Alarm

Setting the Power Mode

Setting the Power Supply Alarm Options

Configuring the Switch Temperature Alarms

Setting a Secondary Temperature Threshold for the Switch

Associating the Temperature Alarms to a Relay

Configuring the FCS Bit Error Rate Alarm

Setting the FCS Error Threshold

Setting the FCS Error Hysteresis Threshold

Configuring Alarm Profiles

Creating or Modifying an Alarm Profile

Attaching an Alarm Profile to a Specific Port