3COM Link 1000 User Manual

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SuperStack® II Switch 1000

User Guide

Agent Software Version 3.1

http://www.3com.com/

Document No. DUA1690-0AAA05 Published June 1997

3Com Corporation ■ 5400 Bayfront Plaza ■ Santa Clara, California ■ 95052-8145

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Unless otherwise indicated, 3Com registered trademarks are registered in the United States and may or may not be registered in other countries.

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Other brand and product names may be registered trademarks or trademarks of their respective holders.

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ONTENTS

BOUT THIS GUIDE

Introduction 1 How to Use This Guide 1 Conventions 2 Related Documentation 2

ETTING STARTED

About the Switch 1000 1-1

Summary of Features 1-1 Port Connections 1-2

10BASE-T Ports 1-2 100BASE-TX Port 1-2 Plug-in Module 1-2 Transceiver Module 1-2 Backbone Port 1-2

Switch Operation and Features 1-3

How Does the Switch Compare to a Bridge? 1-3 Forwarding of Packets 1-3 Intelligent Flow Management 1-4 Full Duplex 1-4 Security 1-5 Resilient Links 1-5 Virtual LANs 1-5 Spanning Tree Protocol 1-5 PACE 1-6

Switch 1000 on Your Network 1-6

Server Connections 1-6 Network Configuration Examples 1-6 Network Segmentation I 1-7 Network Segmentation II 1-8 Desktop Switching 1-9

Unit Overview — Front 1-10

10BASE-T Ports 1-11 100BASE-TX Port 1-11 LEDs 1-11

Unit Overview — Rear 1-12

Power Socket 1-13 Unit Serial Number 1-13 Redundant Power System Socket 1-13 Reset Button 1-13 Console Port 1-13 Plug-in Module Slot 1-13 Transceiver Module Slot 1-13

Ethernet Address 1-13 Unit Defaults 1-14 Managing the Switch 1000 1-14 Quick Start For SNMP Users 1-15

Entering an IP Address for the Switch 1-15

NSTALLATION AND SETUP

Following Safety Information 2-1 Positioning the Switch 1000 2-1

Configuration Rules for Fast Ethernet 2-2 Configuration Rules with Full Duplex 2-2 Installing the Switch 1000 2-4

Rack Mounting 2-4 Stacking the Switch and Other Units 2-4

Wall Mounting 2-5 Powering-up the Switch 2-6 Connecting a Redundant Power System (RPS) 2-6 Connecting Equipment to the Console Port 2-7

Connecting a VT100 Terminal 2-7

Connecting a VT100 Terminal Emulator 2-7

Connecting a Workstation Running SLIP 2-8

ETTING UP FOR MANAGEMENT

Methods of Managing the Switch 1000 3-1

Using the VT100 Management Interface 3-1

Using Telnet 3-2 Managing Over The Network 3-2

IP Addresses 3-2

Obtaining a Registered IP Address 3-3

Navigating the VT100 Screens 3-4

Screen Conventions 3-4

Keyboard Shortcuts 3-5

Correcting Text Entry 3-5 Setting Up the Switch for Management 3-6

Logging On 3-7

After Logging On 3-8 Switch Management Setup 3-9 Logging Off 3-12 Auto Logout 3-12

ANAGING THE SWITCH

Setting Up Users 4-2 Creating a New User 4-3 Deleting a User 4-4 Editing User Details 4-5 Assigning Local Security 4-6 Choosing a Switch Management Level 4-7 Setting Up the Switch Unit 4-9 Setting Up the Switch Ports 4-12 Setting Up the Switch Database (SDB) 4-16

The Database View 4-17 Searching the Switch Database 4-18

By MAC Address 4-18

By Port 4-18 Adding an Entry into the SDB 4-18 Deleting an Entry from the SDB 4-18 Specifying that an Entry is Permanent 4-18

Setting Up Resilient Links 4-19

Configuring Resilient Links 4-20 Creating a Resilient Link Pair 4-21 Deleting a Resilient Link 4-21 Viewing the Resilient Setup 4-22

Setting Up Traps 4-24 Setting Up the Console Port 4-25 Resetting the Switch 4-27 Initializing the Switch 4-28 Upgrading Software 4-29

DVANCED MANAGEMENT

Virtual LANs (VLANs) 5-1

What are VLANs? 5-1 Benefits of VLANs 5-1

1000

How VLANs Ease Change and Movement 5-2 How VLANs Control Broadcast Traffic 5-2

How VLANs Provide Extra Security 5-2 An Example 5-2 VLANs and the Switch 5-3

The Default VLAN and Moving Ports From the Default

VLAN 5-3 Connecting VLANs to a Router 5-3 Connecting Common VLANs Between Switch Units

5-3 Using AutoSelect VLAN Mode 5-3 Using Non-routable Protocols 5-5 Using Unique MAC Addresses 5-5 Extending VLANs into an ATM Network 5-5

VLAN Configurations 5-5

Example 1 5-5 Example 2 5-6 Example 3 5-7

Setting Up VLANs on the Switch 5-8

Assigning a Port to a VLAN When Using Port VLAN

Mode 5-10 Specifying a Backbone Port 5-10 Specifying that a Port is a VLT Port 5-10

Setting Up VLANs Using AutoSelect VLAN Mode 5-11

Specifying Information About the VLAN Server 5-11 Specifying AutoSelect VLAN Mode 5-11

Spanning Tree Protocol 5-12

What is STP? 5-12 How STP Works 5-14

STP Initialization 5-14 STP Stabilization 5-14 STP Reconfiguration 5-14 An Example 5-15

STP Configurations 5-16

Enabling STP on the Switch 5-17 Configuring STP on the Switch 5-18

Configuring the STP Parameters of VLANs 5-18 Configuring the STP Parameters of Ports 5-20

RMON 5-22

What is RMON? 5-22 About the RMON Groups 5-23

Statistics 5-23 History 5-23 Alarms 5-23 Hosts 5-23 Hosts Top N 5-23 Matrix 5-24 Filter 5-24 Capture 5-24 Events 5-24

Benefits of RMON 5-25

How RMON Improves Your Efficiency 5-25 How RMON Allows Proactive Management 5-25

How RMON Reduces the Traffic Load 5-25 RMON and the Switch 5-26 RMON Features of the Switch 5-26 About Alarm Actions 5-28 About Default Alarm Settings 5-29 About the Audit Log 5-29

TATUS MONITORING AND STATISTICS

Summary Statistics 6-2 Port Statistics 6-3 Port Traffic Statistics 6-4 Port Error Analysis 6-6 Status Monitoring 6-8

Fault Log 6-9 Remote Polling 6-10

Modem Cable D-2 RJ45 Pin Assignments D-2

AFETY INFORMATION

Important Safety Information A-1

Power Supply and Fuse A-3 Sockets for Redundant Power System (RPS) A-3 RJ45 Ports A-3 Fiber Ports A-3

L’information de Sécurité Importante A-4

La Source de Courant et Le Fusible A-5 Socle Pour Alimentation Multiple A-5 Les Ports RJ45 A-6 Les Ports Fibre A-6

Wichtige Sicherheitsinformationen A-7

Stromversorgung und Sicherung A-8 Steckdose für Redundant Power System (RPS) A-8 RJ45 Anschlußen A-8 Glasfaser Anschlußen A-8

CREEN ACCESS RIGHTS

ROUBLE-SHOOTING

LEDs C-1 Using the VT100 Interface C-2 Using the Switch C-3

WITCH

ECHNICAL SUPPORT

Online Technical Services F-1

Support from Your Network Supplier F-3 Support from 3Com F-3 Returning Products for Repair F-4

NDEX

3COM C

1000 T

World Wide Web Site F-1 3Com Bulletin Board Service F-1

Access by Analog Modem F-1

Access by Digital Modem F-2 3ComFacts Automated Fax Service F-2 3ComForum on CompuServe Online Service F-2

LOSSARY

ORPORATION LIMITED WARRANTY

LECTRO-MAGNETIC COMPATIBILITY

ECHNICAL SPECIFICATIONS

OUTS

PIN-

Null Modem Cable D-1 PC-AT Serial Cable D-1

BOUT

About This Guide provides an overview of this guide, describes the guide conventions, tells you where to look for specific information and lists other publications that may be useful.

Introduction

This guide provides the information you need to install and configure the SuperStack 24 Port (3C16900A) and the SuperStack II Switch 1000 12 Port (3C16901A) with v3.1 agent software. The functionality of both units is identical, although the local management screens reflect the different number of ports. Where appropriate, these differences are noted.

The guide is intended for use by network administrators who are responsible for installing and setting up network equipment; consequently, it assumes a basic working knowledge of Local Area Networks.

If the information in the Release Notes shipped with your product differs from the information in this guide, follow the Release Notes.

Throughout this guide, the SuperStack II Switch 1000 is referred to as the Switch 1000 or Switch.

HIS

UIDE

II Switch 1000

How to Use This Guide

This table shows where to find specific information in this guide.

If you are looking for... Turn to...

An overview of the Switch 1000 Chapter 1 Information about installing the Switch 1000 into

your network Information about the methods you can use to man-

age the Switch 1000 Information about managing the Switch 1000 Chapter 4 Information about more advanced management fea-

tures; for example VLANs, Spanning Tree and RMON Information about monitoring the status of the

Switch 1000 Safety information Appendix A Information about the access rights for each VT100

screen Trouble-shooting information Appendix C Information about the pin-outs relating to the Switch

1000 Information about the Technical Specifications of the

Switch 1000 Information about the Technical Support available

from 3Com

Chapter 2

Chapter 3

Chapter 5

Chapter 6

Appendix B

Appendix D

Appendix E

Appendix F

2 A

BOUT THIS GUIDE

Conventions

Tab le 1 and Tab le 2 list conventions that are used

throughout this guide.

Table 1

Convention Description

Screen displays

The words “enter” and “type”

[Key] names Key names appear in text in one of two ways:

Menu commands

and

Words in type

Words in

bold-face

Text Conventions

buttons

italicized

type

This typeface represents information as it appears on the screen

When you see the word “enter” in this guide, you must type something, and then press the Return or Enter key. Do not press the Return or Enter key when an instruction simply says “type.”

Referred to by their labels, such as “the

■

Return key” or “the Escape key” Written with brackets, such as [Return] or

■

[Esc].

If you must press two or more keys simultaneously, the key names are linked with a plus sign (+). Example:

Press [Ctrl]+[Alt]+[Del].

Menu commands or button names appear in italics. Example:

From the

Italics emphasize a point or denote new terms at the place where they are defined in the text.

Bold text denotes key features.

Help

menu, select

Contents

Table 2

Icon Notice Type Alerts you to...

Notice Icons

Information note

Caution Risk of personal injury, system damage,

Warning Risk of severe personal injury

Important features or instructions

or loss of data

About the Switch 1000

Part of 3Com’s SuperStack® II range of products, the Switch 1000 is designed to overcome the common problem of insufficient bandwidth for today’s growing network applications, while providing low-cost, high performance networking with little need for configuration. Use the Switch 1000 to provide your users with greater bandwidth, faster throughput and high speed links.

The SuperStack II Switch 1000 is a revision of the LinkSwitch 1000.

Summary of Features

The Switch 1000 has the following features:

12 or 24 Ethernet 10BASE-T ports

■

Fast Ethernet 100BASE-TX port

■

Plug-in Module slot (Asynchronous Transfer

■

Mode (ATM) and Fast Ethernet) Transceiver Module slot (10Mbps Ethernet)

■

Support for up to 500 endstations, unlimited sta-

■

tions on backbone port Four forwarding modes for packets

■

TARTED

Full duplex on all fixed Ethernet and Fast Ethernet

■

ports, and Fast Ethernet Plug-in Module ports Security

■

Resilient Links

■

Support for 16 Virtual LANs (VLANs)

■

Spanning Tree Protocol (STP) per VLAN

■

PACE (Priority Access Control Enabled) for sup-

■

porting multimedia applications over Ethernet 3Com’s SuperStack II architecture:

■

Connects to Redundant Power System

■

Integrated network management

■

19-inch rack or stand-alone mounting

■

SmartAgent support:

■

IP and IPX management over SNMP

■

RMON

■

Repeater and Bridge MIB

■

Broadcast storm control

■

Easy software upgrades

■

BOOTP for automatic IP address configuration

■

Local management

■

Intelligent Flow Management for congestion

■

control

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Port Connections

10BASE-T Ports

The Switch has 12 or 24 10BASE-T ports configured as MDIX (cross-over), which provide a full 10Mbps bandwidth to attached endstations. Maximum segment length is 100m (328ft) over grade 3, 4, or 5 twisted pair cable.

As these ports are configured as MDIX (cross-over), you need to use a cross-over cable to connect to devices whose ports are MDIX-only. Most of the 10BASE-T ports in 3Com devices are MDIX-only.

100BASE-TX Port

The Switch has a single Fast Ethernet 100BASE-TX port configured as MDIX (cross-over), which provides a 100Mbps connection to, for example, a local server. The maximum segment length is 100m (328ft) over grade 5 twisted pair cable.

As this port is configured as MDIX (cross-over), you need to use a cross-over cable to connect to devices whose ports are MDIX-only. Most of the 100BASE-TX ports in 3Com devices are MDIX-only.

Transceiver Module

A slot at the rear of the unit allows you to install any of the 3Com 10Mbps Ethernet Transceiver Modules. When a Transceiver Module is fitted, port 1 automatically switches to become the Transceiver Module port. The Transceiver Module can provide a 10Mbps link to the rest of your network.

Backbone Port

The Switch allows you to specify any port to be a

backbone port

■

Frames with unknown addresses received by the

with the following attributes:

Switch are forwarded to the port.

■

Addresses received on the port are not stored in the Switch Database (the database which contains the device addresses received by the Switch).

A backbone port is typically used to connect the Switch to the backbone of large networks (over 500 MAC addresses). For information about how to specify a backbone port for a new or initialized Switch, refer to “

page 4-9

Setting Up the Switch Unit” on

Plug-in Module

A slot at the rear of the unit can take a Plug-in Module, providing an additional high-speed port. This could be used, for example, to provide a Fast Ethernet or Asynchronous Transfer Mode (ATM) backbone connection to the rest of your network.

You can specify one backbone port for each VLAN defined on the Switch. For more information about how to specify a backbone port for a VLAN, refer to

Setting Up VLANs on the Switch” on page 5-8.

“

About the Switch 1000 1-3

Switch Operation and Features

How Does the Switch Compare to a Bridge?

The table below shows how Switch 1000 operation compares to that of a conventional IEEE 802.1d bridge.

IEEE 802.1d Bridge Switch 1000

Address Learning

Forwarding Mode

Operation when packet buffers full

Spanning Tree Action on

Unknown Destination Address

Database size

All ports All ports except back-

Store and forward Fast Forward, Frag-

Discard packets Invoke Intelligent

Supported Optional

Flood all ports Forward to backbone

4000 addresses 500 addresses

bone port

ment Free, Store and forward, or Intelligent

Flow Management to suppress transmissions at source

port, or forward to all ports

Forwarding of Packets

The table below shows how a packet is processed when it arrives at the Switch 1000.

Packet Source Destination

Any port EXCEPT backbone (Unicast packet)

Any port EXCEPT backbone (Multi/Broadcast packet)

Backbone port (Unicast packet)

Backbone port (Multi/Broadcast packet)

Address

Unknown Forward to back-

Same port as source address

Another port (not backbone)

Not applicable Forward to all ports

Unknown Filter

Known port (not backbone)

Not applicable Forward to all ports

Action

bone port only, or forward to all ports

Filter

Forward to specific port only

(including backbone) in the same VLAN as source port

Forward to known port only

within specific VLAN

In all other ways, Switch 1000 and bridge operation is identical.

You can configure the Switch to forward packets with an unknown destination address to all ports in the same VLAN as the source port. Refer to “

Setting Up the Switch Unit” on page 4-9 for more informa-

tion.

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To best suit your networking requirements, the Switch 1000 allows you to select one of four frame forwarding modes:

■

Fast Forward

— Frames are forwarded as soon as the destination address is received and verified. The forwarding delay, or latency, for all frames in this mode is just 40µs, but with the lack of checking time any error frames received are propagated through the switch.

■

Fragment Free

— A minimum of 64 bytes of the received frame is buffered prior to the frame being forwarded. This ensures that collision fragments are not propagated through the network. The forwarding delay, or latency, for all frames in this mode is 64µs.

■

Store and Forward

— Received packets are buffered in their entirety prior to forwarding. This ensures that only good frames are passed to their destination. The forwarding delay for this mode varies between 64µs and 1.2ms, depending on frame length. In Store and Forward mode, latency is measured as the time between receiving the last bit of the frame and transmitting the first bit. For the Switch 1000, this is 8µs.

■

Intelligent

— The Switch monitors the amount of error traffic on the network and changes the forwarding mode accordingly. If the Switch detects less than 18 errors a second, it operates in Fast Forward mode. If the Switch detects 18 or more errors a second, it operates in Store and Forward mode until the number of errors a second returns to zero.

For more information about selecting forwarding modes, refer to “

page 4-9

Setting Up the Switch Unit” on

Intelligent Flow Management

Intelligent Flow Management (IFM) is a system for controlling congestion on your network. Congestion can be caused by one or more devices sending traffic to an already busy port on the Switch 1000. If a port on the Switch 1000 is connected to another switch or endstation, IFM prevents packet loss and inhibits the device from generating more packets until the period of congestion ends.

IFM should be enabled on a port if it is connected to another switch, or an endstation. IFM should be disabled on a port connected to a repeater.

For more information about enabling IFM, refer to

Setting Up the Switch Ports” on page 4-12.

“

Full Duplex

The Switch 1000 provides full duplex support for all its fixed ports, and Fast Ethernet Plug-in Module ports. Full duplex allows frames to be transmitted and received simultaneously and, in effect, doubles the potential throughput of a link. In addition, full duplex also supports 100BASE-FX cable runs of up to 2km (6562ft).

Full duplex can be enabled on all the relevant ports, all the Fast Ethernet ports, or on individual ports. It is not supported by the Transceiver Module.

About the Switch 1000 1-5

For more information about enabling full duplex, refer to “

Setting Up the Switch Unit” and “Setting

Up the Switch Ports” in Chapter 4.

Security

The Switch 1000 contains advanced security features which guard against users connecting unauthorized endstations to your network. When security is enabled on a port, it enters single address learning mode. In this mode, the port learns a single Ethernet address; once this is learned, the port is disabled if a different address is seen on the port. Until security is disabled, no other address can be learned.

For more information about security, refer to “

Set-

ting Up the Switch Ports” on page 4-12.

Resilient Links

The Resilient Link feature in the Switch 1000 enables you to protect critical links and prevent network downtime should those links fail.

Setting up resilience ensures that should a main communication link fail, a standby duplicate link immediately and automatically takes over the task of the main link. Each main and standby link pair is referred to as a resilient link pair.

For more information about resilient links, refer to

Setting Up Resilient Links” on page 4-19.

“

Virtual LANs

The Switch 1000 has a Virtual LAN (VLAN) feature which allows you to build your network segments without being restricted by physical connections. A VLAN is defined as a group of location- and topology-independent devices that communicate as if they are on the same physical LAN. Implementing VLANs on your network has three main advantages:

It eases the change and movement of devices on

■

IP networks. If an endstation in VLAN 1 is moved to a port in another part of the network, you only need to specify that the new port is in VLAN 1.

It helps to control broadcast traffic. If an endsta-

■

tion in VLAN 1 transmits a broadcast frame, then only VLAN 1 devices receive the frame.

It provides extra security. Devices in VLAN 1 can

■

only communicate with devices in VLAN 2 using a router.

For more information about setting up VLANs on the Switch, refer to “

Virtual LANs (VLANs)” on page

5-1.

Spanning Tree Protocol

The Switch 1000 supports the Spanning Tree Protocol (STP) which is a bridge-based system for providing fault tolerance on networks. STP allows you to implement parallel paths for network traffic, and ensure that:

Redundant paths are disabled when the main

■

paths are operational.

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Redundant paths are enabled if the main traffic paths fail.

Switch 1000 on Your Network

For more information about STP, refer to “

Spanning

Tree Protocol” on page 5-12.

PACE

The Switch 1000 supports PACE (Priority Access Control Enabled) technology, which allows multimedia traffic to be carried over standard Ethernet and Fast Ethernet LANs. PACE provides two features:

■

Implicit Class of Service

— When multimedia traffic is transmitted, it is given a higher priority than other data and is therefore forwarded ahead of other data when it arrives at the Switch. The Implicit Class of Service feature minimizes latency through the Switch and protects the quality of multimedia traffic.

■

Interactive Access

— When two-way multimedia traffic passes over an Ethernet network, interference can occur because access to the bandwidth is unequally allocated to traffic in one direction. The Interactive Access feature allocates the available bandwidth equally in both directions, therefore increasing the quality of the traffic.

For more information about setting up PACE on the Switch, refer to “

Setting Up the Switch Ports” in Chapter 4.

“

Setting Up the Switch Unit” and

Server Connections

When connecting servers to the Switch 1000, use the following rules to ensure that the Switch is operating at maximum efficiency:

■

Ideally, any local server should be connected to the Switch using a 100Mbps port.

■

If that is not possible, connect the local server to a dedicated 10Mbps port.

■

If that is not possible and the local server is connected to a repeated segment where the traffic is mainly local to that segment, disable Intelligent Flow Management (IFM) on the port to which the repeater is connected.

If your network is running a peer-to-peer protocol (for example, Windows 95) and you have multiple endstations connected to the Switch via a repeater, we recommend that you disable IFM on the port to which the repeater is connected.

Network Configuration Examples

The following illustrations show some examples of how the Switch can be placed on your network.

Examples of how the Switch 1000 can be used in a VLAN-based network are given in Chapter 5

Network Segmentation I

This example shows how the Switch 1000 fits into a large corporate network with a Fast Ethernet infrastructure. A Switch is positioned on each floor and servers are centralized in the basement.

Switch 1000 on Your Network 1-7

Figure 1-1

The Switch 1000 in a large corporate network

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Network Segmentation II

This example shows the Switch 1000 in a second workgroup situation. This setup could be that of a small office within a large corporation, or part of a larger corporate network. Most of the switch ports have multiple endstations.

Figure 1-2

The Switch 1000 in a workgroup

Desktop Switching

This example shows Switch 1000 used for a group of heavy-traffic users in a large corporate network. Here switching is brought to the desktop with a single endstation per switch port. A local server is connected using the 100Mbps Fast Ethernet link.

Switch 1000 on Your Network 1-9

Figure 1-3

The Switch 1000 as a desktop switch

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Unit Overview — Front

Figure 1-4

Switch 1000 front view: 3C16901A

top

, 3C16900A

bottom

Unit Overview — Front 1-11

10BASE-T Ports

The Switch has 12 or 24 10BASE-T RJ45 ports configured as MDIX (cross-over), which provide a full 10Mbps bandwidth to attached endstations. The maximum segment length is 100m (328ft) over category 3, 4, or 5 UTP cable.

As these ports are configured as MDIX (cross-over), you need to use a cross-over cable to connect to devices whose ports are MDIX-only. Most of the 10BASE-T ports in 3Com devices are MDIX-only.

100BASE-TX Port

The Switch has a single Fast Ethernet 100BASE-TX RJ45 port configured as MDIX (cross-over), which provides a 100Mbps connection to, for example, a local server. The maximum segment length is 100m (328ft) over category 5 UTP or STP cable.

As this port is configured as MDIX (cross-over), you need to use a cross-over cable to connect to devices whose ports are MDIX-only. Most of the 100BASE-TX ports in 3Com devices are MDIX-only.

LEDs

The table below describes the LED behavior on the Switch. For more details about corrective action in the event of a problem, refer to “

C-1.

LEDs” on page

LED Color Indicates

TCVR Yellow Port 1 is a Transceiver Module fitted to the

Port Status LEDs

Packet Yellow Frames are being transmitted/received on the

Status Green Link is present; port is enabled.

Green flashing Link is present; port is disabled.

Off Link is not present.

Plug-in Module Status LEDs

Packet Yellow Frames are being transmitted/received on the

Status Green Link is present; port is enabled.

Green flashing Link is present; port is disabled.

Green flashing (long on, short off)

Yellow Plug-in Module has failed its Power On Self

Yellow flashing Plug-in Module is not recognized.

Off Link is not present or Plug-in Module is not

Unit Status LEDs

Power

MGMT

Green Switch is powered-up.

Green Switch is operating normally.

Green flashing Switch or Plug-in Module is either down-

Yellow Switch has failed its Power On Self Test.

Yellow flashing Plug-in Module has failed its Power On Self

rear of the unit.

port.

Plug-in Module port.

Refer to the “

OC-3c Module User Guide”

Test (if the MGMT LED is flashing yellow), or the agent software of the Plug-in Module is not installed correctly.

installed in the Switch.

loading software or initializing (which includes a Power On Self Test).

Tes t.

SuperStack II Switch ATM

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Figure 1-5

Switch 1000 rear view

Unit Overview — Rear 1-13

Power Socket

The Switch 1000 automatically adjusts to the supply voltage. The fuse is suitable for both 110V A.C. and 220–240V A.C. operation. For information on replacing fuses, refer to Appendix A

Unit Serial Number

You may need this serial number for fault reporting purposes.

Redundant Power System Socket

Use one of these sockets to connect a SuperStack II Redundant Power System (RPS) to the unit. You can use either socket. Refer to “

dant Power System (RPS)” on page 2-6.

Connecting a Redun-

Reset Button

Using the reset button simulates a power-off/on cycle. This has the same effect as carrying out a reset via the VT100 interface; refer to “

Switch” on page 4-27.

Console Port

Connect a terminal to the console port to carry out remote or local out-of-band configuration and management. The console port is set to auto-baud, 8 data bits, no parity, and 1 stop bit.

Resetting the

Plug-in Module Slot

Use this slot to install a Plug-in Module. The Module can be used to provide a high speed link to the rest of your network. 3Com provides a range of Plug-in Modules; contact your supplier for availability.

When a Plug-in Module is not installed, ensure the blanking plate is secured in place.

Transceiver Module Slot

Use this slot to connect a Transceiver Module and provide a 10Mbps link to the rest of the network. Port 1 is automatically switched from the front 10BASE-T port to the Transceiver Module port when a Module is installed. 3Com provides a range of Transceiver Modules; contact your supplier for availability.

When a Transceiver Module is not installed, ensure the blanking plate is secured in place.

Ethernet Address

This label shows the unique Ethernet (or MAC) address assigned to the unit.

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Unit Defaults

The following table shows the factory defaults for the Switch 1000 features.

Port Status Forwarding Mode Intelligent Flow

Management Duplex Mode Virtual LANs

PACE Spanning Tree (STP) Power On Self Test

(POST) System Alarm

(broadcast bandwidth used)

System Alarm (errors per 10,000 packets)

System Alarm (bandwidth used)

System Alarm (percentage of frames forwarded)

Enabled

Fast Forward

Enabled

Half duplex on all relevant ports

All ports use Port VLAN Mode and belong to the Default VLAN (VLAN 1)

Disabled

Normal (Fast Boot)

Enabled

■

High threshold: 20% — Notify and Blip

■

Low threshold: 10% — No action

Enabled

■

High threshold: 2% — Notify

■

Low threshold: 1% — No action

Enabled

■

High threshold: 85% — No action

■

Low threshold: 50% — No action

Enabled

■

High threshold: 85% — No action

■

Low threshold: 50% — No action

Managing the Switch 1000

The menu-driven interface built into the Switch 1000 is known as the VT100 interface. You can access it using a VT100 terminal, or a PC using terminal emulation software. You can connect the terminal directly to the Switch or through a modem. You can also access the VT100 interface remotely using Telnet running over the TCP/IP protocol.

Remote management is also possible using a Network Manager from 3Com’s Transcend range. The management protocol is SNMP (Simple Network Management Protocol) and any SNMP-based management facility can manage the unit if the Management Information Base (MIB) is installed correctly in the management workstation. The Switch 1000 supports SNMP over both IP and IPX protocols.

product

Quick Start For SNMP Users

This section describes how to get started if you want to use an SNMP Network Manager to manage the Switch. It assumes you are already familiar with SNMP management.

If you are using IP and you have a BOOTP server

■

set up correctly on your network, the IP address for the Switch is detected automatically and you can start managing the Switch without any further configuration.

If you are using the IPX protocol, the Switch

■

1000 is allocated an IPX address automatically. You can start the SNMP Network Manager and begin managing the Switch.

If you are using IP without a BOOTP server, you

■

must enter the IP address of the Switch before the SNMP Network Manager can communicate with the device. To do this, refer to “

IP Address for the Switch” below.

Entering an

Quick Start For SNMP Users 1-15

At the Main Banner screen, press [Return] to dis-

play the Logon screen. Log on using the default user name

admin

(no password is required). Select

OK. The Main Menu is displayed. From this menu, select

the MANAGEMENT SETUP option. The Switch Management Setup screen is displayed.

On the Management Setup screen, fill in the follow-

ing fields:

Device IP Address

■

Device SubNet Mask (if necessary)

■

Default Router (if necessary)

■

For further information on the Management Setup screen, refer to “

Setting Up the Switch for Manage-

ment” on page 3-6.

If you need the Switch 1000 to send SNMP traps to

the Network Manager, you may need to set up the address of the Network Manager in the Trap Table. Refer to “

Setting Up Traps” on page 4-24.

If you need more information about IP and IPX, refer

Managing Over The Network” on page 3-2.

to “

Entering an IP Address for the Switch

Connect a terminal to the console port of the

Switch 1000, refer to “

Connecting a VT100 Terminal” on page 2-7. The terminal should be config-

ured to 9600 line speed (baud rate), 8 data bits, no parity, and 1 stop bit.

Press [Return] one or more times until the Main

Banner screen appears.

3Com Network Managers such as Transcend Enterprise Manager for Windows may automatically configure the Switch 1000 to send traps to them. Please read the documentation supplied with your network management software.

When you have finished with the Management

Setup screen, select OK.

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ETTING STARTED

NSTALLATION AND

Following Safety Information

Before installing or removing any components from the Switch, or carrying out any maintenance procedures, you must read the safety information provided in Appendix A

of this guide.

Positioning the Switch 1000

The Switch is suited for use in the office where it can be wall-mounted, mounted in a standard 19-inch equipment rack, or free standing. Alternatively, the unit can be rack-mounted in a wiring closet or equipment room. A wall-mounting / rack-mounting kit, containing two mounting brackets and six screws, is supplied with the Switch.

When deciding where to position the unit, ensure that:

ETU

Cabling is away from:

■

Sources of electrical noise such as radios,

■

transmitters and broadband amplifiers. Power lines and fluorescent lighting fixtures.

■

Water or moisture cannot enter the case of the

■

unit. Air-flow around the unit and through the vents in

■

the side of the case is not restricted. We recommend that you provide a minimum 25mm (1in.) clearance.

No objects are placed on top of the unit.

■

Units are not stacked more than four high if

■

free-standing.

You are able to meet the configuration rules

■

detailed in the following section. The unit is accessible and cables can be con-

■

nected easily.

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NSTALLATION AND SETUP

Configuration Rules for Fast Ethernet

The topology rules for 100Mbps Fast Ethernet are slightly different to those for 10Mbps Ethernet. Figure 2-1 illustrates the key topology rules and provides examples of how they allow for large-scale Fast Ethernet networks.

The key topology rules are:

■

Maximum UTP cable length is 100m (328ft) over category 5 cable.

■

A 412m (1352ft) fiber run is allowed for connecting switch to switch, or endstation to switch, using half-duplex 100BASE-FX.

■

A total network span of 325m (1066ft) is allowed in single-repeater topologies (one hub stack per wiring closet with a fiber run to the collapsed backbone). For example, a 225m (738ft) fiber downlink from a repeater to a router or switch, plus 100m (328ft) UTP run from a repeater out to the endstations.

With full duplex, the Ethernet topology rules are the same, but the Fast Ethernet rules are:

■

Maximum UTP cable length is 100m (328ft) over category 5 cable

■

A 2km (6562ft) fiber run is allowed for connecting switch-to-switch, or endstation-to-switch

Configuration Rules with Full Duplex

The Switch provides full duplex support for all its fixed Ethernet and Fast Ethernet ports, and Fast Ethernet Plug-in Module ports. Full duplex allows frames to be transmitted and received simultaneously and, in effect, doubles the potential throughput of a link.

Configuration Rules with Full Duplex 2-3

Figure 2-1

Fast Ethernet configuration rules

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NSTALLATION AND SETUP

Installing the Switch 1000

Rack Mounting

The Switch is 1.5U high and fits in most standard 19-inch racks.

CAUTION: Disconnect all cables from the Switch before continuing. Remove all self adhesive pads from the underside of the unit, if fitted.

Place the unit the right way up on a hard flat surface, with the front facing towards you.

Locate a mounting bracket over the mounting holes on one side of the unit, as shown in Figure 2-2.

Insert the three screws and fully tighten with a suitable screwdriver.

Repeat steps 2 and 3 for the other side of the unit.

Insert the unit into the 19-inch rack and secure with suitable screws (not provided). Ensure that ventilation holes are not obstructed.

Connect network cabling.

Stacking the Switch and Other Units

If the units are free standing, up to four units can be placed on top of one another. If mixing a variety of SuperStack II Switch and Hub units, the smaller units must be positioned at the top.

The Switch is supplied with four self-adhesive rubber pads. Apply the pads to the underside of the unit, stick one in the marked area at each corner of the unit. Place the units on top of each other, ensuring that the pads of the upper unit line up with the recesses of the lower unit.

Figure 2-2

Fitting a bracket for rack mounting

Wall Mounting

A single Switch can be wall-mounted.

Installing the Switch 1000 2-5

CAUTION:

Disconnect any cables from the unit before continuing. Remove self-adhesive pads from the underside of the unit if they have been previously fitted.

Place the Switch the right way up on a hard flat sur-

face, with the front facing towards you. Locate a mounting bracket over the mounting

holes on one side of the unit, as shown in Figure 2-3.

Insert the two screws and tighten with a suitable

screwdriver. Repeat for the other side of the unit.

Ensure that the wall you are going to use is smooth,

flat, dry and sturdy. Attach a piece of plywood, approximately 305mm x 510mm x 12mm (12in. x 20in. x 0.5in.) securely to the wall if necessary, and mount the Switch as follows:

Position the base of the unit against the wall (or

plywood) ensuring that the ventilation holes face sidewards. Mark on the wall the position of the screw holes in both wall brackets. Drill the four holes.

Figure 2-3

Fitting a bracket for wall mounting

Using suitable fixings and screws (not provided),

attach the Switch unit securely to the wall or plywood.

Connect network cabling.

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NSTALLATION AND SETUP

Powering-up the Switch

Connect the power cord to the IEC socket on the rear of the Switch, and to your mains socket.

The Switch has no ON/OFF switch; the only method of connecting or disconnecting mains power is through the power cord.

The Switch enters a Power On Self Test (POST). The time taken for the test to complete is dependent on the type of POST configured (refer to “

Management Setup” on page 3-9 for details of how

to configure the type of POST). For a new Switch that is being installed for the first time, power-up takes approximately 13 seconds.

Check the status LEDs to ensure the Switch is operating correctly (refer to “

Switch

LEDs” on page 1-11).

Connecting a Redundant Power System (RPS)

You can connect a SuperStack® II Redundant Power System (RPS) to the Switch.

At +5V, the current requirement for the Switch is

4.8A, including any Transceiver Module that might be fitted, but excluding a Plug-in Module. Check the documentation supplied with your Plug-in Module for power consumption figures.

For most configurations, you need only one Superstack II RPS output, and this can be connected to either of the two sockets on the rear of the unit.

If the current consumption of the Switch plus any Plug-in Module exceeds the capability of the RPS (8.5A), you need a SuperStack II Advanced RPS with one Advanced RPS 100W Module.

If the RPS is used incorrectly, its Output Fault LED lights yellow.

You should check the documentation supplied with the RPS or Advanced RPS to see if the outputs can be used in parallel.

Connecting Equipment to the Console Port

The Switch console port settings are set to:

8 data bits

■

no parity

■

1 stop bit

■

The terminal connected to the console port on the Switch must be configured with the same settings. This procedure is described in the documentation supplied with the terminal. If you have enabled auto-configuration for the Switch, the terminal’s line speed (baud rate) is detected automatically.

Connection to the console port can be direct for local management, or through a modem for remote management. The maximum baud rate the auto-configuration detects is 19,200 baud.

Appropriate cables are available from your local supplier. If you need to make your own cables, pin-outs are detailed in Appendix D

Connecting Equipment to the Console Port 2-7

Connecting a VT100 Terminal

To connect a VT100 terminal directly to the console port on the Switch, you need a standard null modem cable:

Connect one end of the cable to the console port

on the Switch, and the other to the console port on the VT100 terminal.

Ensure that your terminal is set to:

8 data bits

■

no parity

■

1 stop bit

■

If auto-configuration is enabled for the Switch, the terminal’s line speed (baud rate) is detected automatically.

Connecting a VT100 Terminal Emulator

Ensure that the workstation is running a suitable

terminal emulation package. There are many available; contact your local supplier for further details.

If you are using a PC, you need a null modem

cable with an appropriate connector. Connect one end of the cable to the workstation, and the other end to the console port on the Switch.

Ensure that your workstation is set to:

8 data bits

■

no parity

■

1 stop bit

■

If auto-configuration is enabled for the Switch, the workstation’s line speed (baud rate) is detected automatically.

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NSTALLATION AND SETUP

Connecting a Workstation Running SLIP

You can communicate with the Switch via the console port from a workstation running SLIP (Serial Line Internet Protocol). In this way, you can perform out-of-band management using Telnet or SNMP.

Cables required for this connection depend on the type of workstation you are using. You must configure the workstation to run SLIP. Refer to the documentation supplied with the workstation for more details.

You must configure the console port of the Switch to accept SLIP and set up the SLIP parameters (address and subnet mask). Refer to “

agement Setup” on page 3-9.

You may need a 5-wire cable when running SLIP. Two of the wires are required for Flow Control.

Switch Man-

ETTING

FOR

Methods of Managing the Switch 1000

You can manage the Switch in four ways:

Using the VT100 interface by connecting a VT100

■

terminal (or workstation with terminal emulation software) to the Switch console port.

Using the VT100 interface over a TCP/IP network

■

using a workstation running VT100 terminal emulation and Telnet.

Using the VT100 interface by connecting a work-

■

station running SLIP to the Switch console port. Using an SNMP Network Manager over a net-

■

work running either the IP or IPX protocol. Each Network Manager provides its own user interface to the management facilities.

Using the VT100 Management Interface

The menu-driven user interface built into the Switch is known as the VT100 or Local Manage- ment interface. The VT100 management interface provides a forms-based structure with pre-defined security levels, enabling access to be restricted to particular users. The Switch can support up to four management user sessions concurrently (for example one console port and three Telnet connections).

ANAGEMENT

You can establish VT100 management communication with the Switch through two different interfaces:

■

Via the Console Port

local management interface using a VT100 terminal, or PC using suitable terminal emulation software. The terminal can be connected directly to the Switch, or through a modem. You can also connect a management workstation running SLIP to the console port, which allows you to use out-of-band Telnet. The workstation can be connected directly or remotely, through a modem. This method provides a way of managing the Switch in situations where the LAN is not providing a reliable service, where the Network Manager does not have direct LAN connectivity, or when a Network Manager does not support SNMP.

■

Via a Network Connection

agement facility is also accessible via Telnet over a network running the TCP/IP protocol. The management available through Telnet is exactly the same as that of a locally connected terminal. The Telnet application requires a VT100 terminal, or PC using suitable terminal emulation software.

— You can access the

— The local man-

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Using Telnet

Any Telnet facility that emulates a VT100 terminal should be able to communicate with the Switch over a TCP/IP network. Up to three active Telnet sessions can access the Switch concurrently. If a connection to a Telnet session is lost inadvertently, the connection is closed by the Switch after 2–3 minutes of inactivity.

Before you can start a Telnet session you must set up the IP parameters described in “

ment Setup” on page 3-9.

3: S

ETTING UP FOR MANAGEMENT

Switch Manage-

Managing Over The Network

Any Network Manager running the Simple Network Management Protocol (SNMP) can manage the Switch, provided the MIB (Management Information Base) is installed correctly on the management workstation.

Each Network Manager provides its own user interface to the management facilities. 3Com's Transcend facilities for managing the Switch.

range of Network Managers all have

To open the Telnet session, you must specify the IP address of the device you want to manage. Check the user manual supplied with the Telnet facility if you are unsure how to do this.

Once the connection is established, the main banner of the VT100 management interface is displayed and you can log on.

The Switch supports SNMP over both IP and IPX protocols.

IP Addresses

If you are uncertain about IP addresses that may be assigned to your devices, contact your network administrator first.

To operate correctly, each device on your network must have a unique IP address. IP addresses have the format n.n.n.n where n is a decimal number between 0 and 255. An example IP address is:

191.128.40.120

The IP address can be split into two parts:

■

The first part (191.128 in the example) identifies the network on which the device resides.

■

The second part (40.120 in the example) identifies the device within the network.

If your network is internal to your organization only, you may use any arbitrary IP address. We suggest you use addresses in the series 191.100.X.Y, where X and Y are numbers between 1 and 254. Use 191.101.X.Y for the SLIP address.

If your network has a connection to the external IP network, you will need to apply for a registered IP address. This system ensures that every IP address used is unique; if you do not have a registered IP address, you may be using an identical address to someone else and your network will not operate correctly.

Obtaining a Registered IP Address

InterNIC Registration Services is the organization responsible for supplying registered IP addresses. The following contact information is correct at the time of publication:

Network Solutions Attn: InterNIC Registration Service 505, Huntmar Park Drive Herndon VA 20170 U.S.A.

Managing Over The Network 3-3

Telephone: (1) (703) 742 4777

If you have access to the Internet, you can find further information about InterNIC by entering the following URL into your web browser:

http:/ /www. inte rnic .net

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Navigating the VT100 Screens

Screen Conventions

To differentiate types of information, the VT100 screens use the following conventions:

Type of information

Choice Field

Entry Field [

Button

List Box

Shown on screen

Description

as...

♦text♦

Text enclosed with markers is a list from which you can select one option only. Press [Space] to cycle through the options. Press [Down Arrow] or [Return] to move to the next field.

text

] Text enclosed in square brackets on the screen is a

you to enter text, numeric data or hexadecimal data from the keyboard. Password fields are hidden, which means that the text you type is not shown on the screen. In some cases a text entry field has a default entry. If you wish to replace the default, simply enter a new value for this field; the default entry is erased. Press [Down Arrow] or [Return] to move to the next field.

Text for a button is always shown in uppercase letters. A button carries out an action, for example, OK or CANCEL. To operate a button, move the cursor to the button and press [Return].

monitor manager security

A list box allows you to select one or more items from a list. There are several keys that allow you to use a list box.

■

[Return] moves the cursor to the next field and actions your selections.

■

[Space] toggles through the options in a choice field or selects and deselects an entry in the list box. List box selections are highlighted.

■

[Down Arrow] moves item by item down the list box until it reaches the end of the list. At the end of the list it moves the cursor to the next field.

■

[Ctrl] + [U] moves the cursor one page up the list box.

■

[Ctrl] + [D] moves the cursor one page down the list box.

text entry

field. A text entry field allows

Navigating the VT100 Screens 3-5

Keyboard Shortcuts

There are several special characters or combinations of characters that allow you to make shortcuts.

[Tab] allows you to move from one field to the next, on any screen, without making any changes.

[Return] moves you to the next field on a form after you have made changes to the data in a field.

[Left Arrow] moves you to the previous field on the screen or the next character in an editable field.

[Right Arrow] moves you to the next field on the screen or the previous character in an editable field.

[Ctrl] + [R] refreshes the screen.

[Ctrl] + [B] moves the cursor to the next button.

[Ctrl] + [P] aborts the current screen and returns you to the previous screen.

[Ctrl] + [N] actions the inputs for the current screen and moves to the next screen.

Correcting Text Entry

Use [Delete] on a VT100 terminal or [Backspace] on a PC. This moves the cursor one space to the left and deletes a character.

If you are using Telnet or a terminal emulation program you may find that some of the Control keys do not operate or that they activate other functions. Check carefully in the manual accompanying your Telnet or terminal emulation software before using the Control keys.

[Ctrl] + [K] displays a list of the available key strokes.

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Setting Up the Switch for Management

The following sections describe how to get started if you want to use an SNMP Network Manager to manage the Switch. It assumes you are already familiar with SNMP management. If not, we recommend the following publication:

“The Simple Book”

by Marshall T. Rose ISBN 0-13-812611-9 Published by Prentice Hall

■

If you are using IP and you have a BOOTP server set up correctly on your network, the IP address for the Switch is detected automatically and you can start managing the Switch without any further configuration.

■

If you are using the IPX protocol, the Switch is allocated an IPX address automatically. You can start the SNMP Network Manager and begin managing the Switch.

■

If you are using IP without a BOOTP server, you must enter the IP address of the Switch before the SNMP Network Manager can communicate with the device. To do this, take the following steps:

Figure 3-1

At your terminal, press [Return] two or more times until the Switch 1000 Main Banner is displayed (shown in Figure 3-1). The console port detects the line speed (baud rate) from these keystrokes and defaults to:

■

Data bits, parity and stop bit values cannot be changed.

At the Main Banner, press [Return] to display the Logon screen.

Main Banner

auto-baud 8 data bits no parity 1 stop bit

Logging On

At the Logon screen displayed in Figure 3-2, enter your user name and password (note that they are both case-sensitive):

If you have been assigned a user name and pass-

■

word, enter those details. If you are logging on for the first time (after

■

installation or initialization), use a default user name and password to match your access requirements. The defaults are shown in Table 3-1. If you are setting up the Switch for management, we suggest that you log on first as

admin

Setting Up the Switch for Management 3-7

Figure 3-2

Logon screen

Tab le 3 -1

User Name Default

monitor monitor monitor — this user can view, but not

manager manager manager — this user can access and

security security security — this user can access and

admin (no password) security — this user can access and

Default Users

Access Level

Password

change all manageable parameters

change the operational parameters but not special/security features

change all manageable parameters

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After Logging On

When you have successfully logged on to the Switch, the Main Menu screen is displayed as shown in Figure 3-3. From here, you can select the options needed to manage the unit. Refer to the screen map on page 4-1

If you have installed an ATM OC-3c Module into the Switch, the Main Menu screen contains an ATM CONFIGURATION option. Refer to the “SuperStack II Switch ATM OC-3c Module User Guide” for more information.

Access to options depends on the access level you have been assigned. Access rights to the VT100 screens for the Switch are listed in Appendix B

Figure 3-3

Main Menu screen

If you are a user with

security

access level, and are using the management facility for the first time, we suggest that you:

■

Assign a new password for your user, using the Edit User screen, as described in “

Editing User

Details” on page 4-5.

■

Log on as each of the other default users, and change their passwords using the Edit User screen.

■

Create any new users, in addition to the default ones. To do this, you assign each user a name, password and security level, as described in “

Cre-

ating a New User” on page 4-3.

Switch Management Setup

The Management Setup screen allows you to configure IP, IPX and SLIP parameters for the Switch. This screen also allows you to display screens for setting up the console port and traps.

To access the Setup screen, from the Main Menu screen, select the MANAGEMENT SETUP option. The Setup screen appears as shown in Figure 3-4.

If you change some of the following parameters, the Switch must be reset for the change to take effect. Reset the Switch by selecting OK and pressing the Reset button on the rear of the unit. Refer

Unit Overview — Rear” on page 1-12.

to “

The screen shows the following:

MAC Address

This read-only field shows the MAC address of the Switch unit, which is required for management.

Power On Self Test Type

field allows you to determine the type of self-test that the Switch carries out when it is powered-up. If the field is set to

Normal,

Fast Boot — a basic confidence check lasting approximately 13 seconds. When the Switch performs a Fast Boot, it carries out the following tests:

Checksum test of boot and system areas of Flash

■

memory System memory tests

■

MAC address verification test

■

System timer test

■

Normal / Extended

This

the Switch performs a

Figure 3-4

■

If the field is set to an Extended test which may take up to 70 seconds to complete. When the Switch performs an Extended test, it carries out the Fast Boot tests and more extensive tests on system memeory and ASIC memory. The default setting for the field is

Setting Up the Switch for Management 3-9

Management Setup screen

CAM (Contents Addressable Memory) tests Console port tests Internal packet forwarding tests ASIC (Application Specific Integrated Circuit) tests ASIC memory tests Switch–Plug-in Module interface test Plug-in Module packet forwarding tests Plug-in Module ASIC tests Plug-in Module ASIC memory tests

Extended

, the Switch performs

Normal

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ETTING UP FOR MANAGEMENT

If you suspect that there is a problem with the Switch that has not been detected by the Normal tests, set this field to Extended and reset the Switch (refer to “

Resetting the Switch” on page 4-27).

If you set the Switch to perform an Extended test, the Switch must be disconnected from the rest of your network when it is powered-up. The Switch fails an Extended test if it receives any network traffic during the test.

Device IP Address

If you are using IP, a unique IP address must be specified in this field. If you do not know the IP address of the Switch, consult your network administrator. You must reset the Switch after changing this parameter.

Device SubNet Mask

If you are using IP, enter a

suitable network mask. For a Class B IP address,

255.255.0.0 is suitable. For more information, contact your network administrator. You must reset the Switch after changing this parameter.

Default Router

If a default router exists on your network, enter the IP address of the router. You must reset the Switch after changing this parameter.

BOOTP Select

Enabled / Disabled

If BOOTP is enabled and you have a BOOTP server on your network, an IP address is automatically mapped to the Switch when it is first powered up. In addition to mapping an IP address, BOOTP can also assign the subnet mask and default router. Using a BOOTP server avoids having to configure devices individually.

SLIP Address

If you are using SLIP, enter an address that has a network part different to the network address of the Switch. For more information, contact your network administrator. You must reset the Switch after changing this parameter.

SLIP SubNet Mask

Enter a suitable SubNet Mask. For a Class B address, 255.255.0.0 is suitable. For more information, contact your network administrator. You must reset the Switch after changing this parameter.

There are four entries under the following four fields; one for each data link layer protocol that can be used by IPX:

IPX Network

This read-only field shows the address of the network for this protocol. This address is learned automatically from the local IPX router or NetWare File Server, and you do not need to change it.

This read-only field shows the node address

Node

of the Switch which is learned automatically.

Status

Enabled / Disabled

If this field is set to Enabled, you have access to the medium-access protocol. Set this field to Disabled if you wish to prevent access for security reasons.

Data Link Protocol

This read-only field shows the

name of the IPX data link layer protocol.

Setting Up the Switch for Management 3-11

SETUP TRAPS

Select this button to display the setup screen for trap parameters. Trap setup is described in “

CONSOLE PORT

Setting Up Traps” on page 4-24.

Select this button to display the setup screen for console port parameters. Console port setup is described in “

Setting Up the Console

Port” on page 4-25.

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Logging Off

If you have finished using the VT100 management interface, select the LOGOFF option from the bottom of the Main Menu screen. If you accessed the VT100 management interface using a Telnet session or modem connection, the connection is closed automatically.

Auto Logout

There is a built-in security timeout on the VT100 interface. If you do not press any keys for 3 minutes, the management facility warns you that the inactivity timer is about to expire. If you do not press a key within 10 seconds, the timer expires and the screen is locked; any displayed statistics continue to be updated. When you next press any key, the display changes to the Auto Logout screen.

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ETTING UP FOR MANAGEMENT

Figure 3-5

Auto Logout screen

The Auto Logout screen (shown in Figure 3-5

) requests you to enter your password again. If the password is correctly entered, the screen that was active when the timer expired is displayed. If you make a mistake entering your password, you are returned to the Logon screen.

ANAGING

WITCH

1000

Chapters 4, 5 and 6 describe all management facilities for the Switch 1000. While following steps in these chapters, you may find the screen map below useful:

If an ATM OC-3c Module is installed in the Switch, extra screens are available. Refer to the “SuperStack Guide” for more information.

II Switch ATM OC-3c Module User

Figure 4-1

Screen map

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4: M

Setting Up Users

From the Main Menu, select USER ACCESS LEVELS. The User Access Levels screen appears as shown in

Figure 4-2

From this screen you can access:

■

LOCAL SECURITY screen

set up access levels for users on the Switch.

■

CREATE USER screen

create up to 10 users in addition to the default users set up on the Switch.

■

DELETE USERS screen

delete users from the Switch. The default users cannot be deleted.

■

EDIT USER screen

your own password and community string. You cannot change details for other users.

ANAGING THE SWITCH

— This allows you to

— This allows you to change

1000

Figure 4-2

User Access Levels screen

Creating a New User

These steps assume the User Access Levels screen is displayed.

Select the CREATE USER option. The Create User

screen is displayed, as shown in Figure 4-3 Fill in the fields and assign an access level for the

new user. When the form is complete, select OK.

Creating a New User 4-3

The Create User screen shows the following fields:

User Name

Type in the name of this new user. The name can consist of up to 10 characters and is case-sensitive.

Password

Type in the password for this new user. The password can consist of up to 10 characters and is case-sensitive. For security reasons, the password is not displayed on screen.

Access Level

Assign an access level for this new

user, as follows:

monitor

■

— access to view, but not change, a subset of the manageable parameters of the Switch

secure monitor

■

manager

■

— access to all the manageable param-

— as

monitor

eters of the Switch, except security features

Figure 4-3

■

Community String

identical to the user name is generated. You can change this to any text string of 32 characters or less. The community string is only needed for SNMP access. If you are using a remote SNMP Network Manager, the community string specified in the Network Manager’s database must be the same as that for the device.

If you enter a community string that is greater than 32 characters, it is truncated to 32 characters.

Create User screen

specialist security

— as

— access to all manageable parameters

of the Switch

manager

By default, a community string

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Deleting a User

These steps assume the User Access Levels screen is displayed.

Select the DELETE USERS option. The Delete Users screen is displayed, as shown in Figure 4-4

Use the spacebar to highlight the user that you want to delete. Note that you cannot delete default users or the current user (that is, yourself).

Select DELETE USERS.

ANAGING THE SWITCH

1000

Figure 4-4

Delete Users screen

Editing User Details

These steps assume the User Access Levels screen is displayed.

Select the EDIT USER option. The Edit User screen is

displayed, as shown in Figure 4-5 Fill in the fields as required.

When you have completed the changes, select OK.

The Edit User screen shows the following fields:

Editing User Details 4-5

User Name

This read-only field shows the name of the user. This field cannot be changed; if you need to change the user name, you must delete this user and create a new one.

Old Password

To change the user’s password, enter

the current password in this field.

New Password

This field allows you to enter a new

password for the user.

Confirm Password

This field allows you to

re-enter the new password.

Community String

This field allows you to enter a

community string for the user.

If you forget your password while logged out of the Switch VT100 interface, contact your local technical support representative who will advise on your next course of action.

Figure 4-5

Edit User screen

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Assigning Local Security

The Local Security screen shows a matrix of options for access method (Console Port, Remote Telnet, Community-SNMP) and access level.

These steps assume the User Access Levels screen is displayed.

Select the LOCAL SECURITY option. The Local Security screen is displayed, as shown in Figure 4-6

Fill in the fields as required.

When you have filled in the form, select OK.

Access options are:

1000

Figure 4-6

Local Security screen

Console Port

Enabled / Disabled

To prevent access to the management facilities via the console port, disable access to the facility for each access level. Console port access for

Security

is enabled and cannot be changed. This prevents accidental disabling of all access levels from management.

Remote Telnet

Enabled / Disabled

Telnet is an insecure protocol. You may want to disable all access to the management facilities via Telnet if there is important or sensitive data on your network.

Community-SNMP

Enabled / Disabled

The Switch can be managed via SNMP using a remote Network Manager. Community-SNMP does have some simple security features, but it is an insecure protocol. You may want to disable all access to the management facilities if there is important or sensitive data on your network.

Choosing a Switch Management Level

The Switch Management screen allows you to:

Choose between managing a port, the unit, or a

■

VLAN Display screens for setting up the Switch

■

Display a screen for managing the Switch Data-

■

base Display screens for managing resilient links

■

Display screens for managing STP

■

Display screens showing statistics

■

From the Main Menu, select SWITCH MANAGEMENT. The Switch Management screen is displayed, as shown in Figure 4-7

Figure 4-7

Choosing a Switch Management Level 4-7

Switch Management screen for Port level (3C16900A)

Management Level

choose

Figure 4-7

Port

, the screen is displayed similar to

, and all options at the foot of the screen

Port / Unit / VLAN

relate to an individual port. If you choose screen appears similar to Figure 4-8 relate to the Switch unit. If you choose screen appears similar to Figure 4-9

If you

Unit

, the

, and all options

VLAN

, the

, and all options

relate to VLANs.

Port ID

1 / 2 / 3 / ... 24 / 25 / 26

1 / 2 / 3 / ... 12 / 13 / 14

(3C16900A)

(3C16901A) If you choose to manage the Switch at port level, enter the particular port number into this field before selecting the next screen. For 3C16900A, ports 1–24 are the 10BASE-T ports, port 25 is the Plug-in Module port at the rear of the unit, and port 26 is the 100BASE-TX port.

Figure 4-8

For 3C16901A, ports 1–12 are the 10BASE-T ports, port 13 is the Plug-in Module port at the rear of the unit, and port 14 is the 100BASE-TX port.

Switch Management screen for Unit level

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1000

Use this button to display screens for managing Spanning Tree Protocol (STP) information for the level of management you have chosen (port or VLAN). Refer to “

Spanning Tree Protocol” on page

5-12.

STP is not supported over Asynchronous Transfer Mode (ATM). Consequently, if you specify that you want to manage the Plug-in Module and the Switch has an ATM OC-3c Module installed, the STP button is not displayed.

SERVER

Use this button to display the VLAN Server screen, used for entering the IP address and community string of a VLAN server. For more information about VLAN servers, refer to “

Virtual LANs

(VLANs)” on page 5-1.

STATS

Use this button to display statistics screens for the level of management you have chosen (port or unit). Refer to Chapter 6

SDB

Use this button to display the Unit Database

View screen, which is used to manage the Switch Database. Refer to “

The Database View” on page

4-17.

RESILIENCE

Use this button to display resilient link management screens for the level of management you have chosen (port or unit). Refer to “

Setting

Up Resilient Links” on page 4-19.

You cannot set up resilient links if the Switch uses Spanning Tree (STP). Consequently, the RESILIENCE button is not displayed if STP is enabled.

Figure 4-9

SETUP

the level of management you have chosen (port, unit or VLAN). For information about the Port Setup and Unit Setup screens, refer to “

the Switch Ports” and “Setting Up the Switch Unit”

in this chapter. For information about the VLAN Setup screen, refer to “

Switch” on page 5-8.

Switch Management screen for VLAN level

Use this button to display setup screens for

Setting Up

Setting Up VLANs on the

Setting Up the Switch Unit

With the Switch Management screen displayed, choose the management level SETUP button.

The Unit Setup screen is displayed as shown in

Figure 4-10

. The screen shows the following:

Unit

, then select the

Setting Up the Switch Unit 4-9

Unit Name

This read-only field shows the type of

device.

sysName

This field takes its name from the MIB II System Group object. You can edit the first 30 characters of this field to make the name more meaningful. This name is displayed on the Main Banner when you first access the VT100 screens, and is also accessible to an SNMP Network Manager.

Forwarding Mode

Store and Forward / Intelligent

Fast Forward / Fragment Free /

This field allows you

to set the forwarding mode for the Switch:

Fast Forward

■

— Frames are forwarded as soon as the destination address is received and verified. The forwarding delay, or latency, for all frames in this mode is just 40µs but with the lack of checking time, error frames are propagated onto the network.

Fragment Free

■

— A minimum of 512 bits of the received frame is buffered prior to the frame being forwarded. This ensures that collision fragments are not propagated through the network. The forwarding delay, or latency, for all frames in this mode is 64µs.

Figure 4-10

Store and Forward

■

ered in their entirety prior to forwarding. This ensures that only good frames are passed to their destination. The forwarding delay for this mode varies between 64µs and 1.2ms, depending on frame length. In this mode the latency, measured as the time between receiving the last bit of the frame and transmitting the first bit, is 8µs.

Intelligent

■

of error traffic on the network and changes the forwarding mode accordingly. If the Switch detects less than 18 errors a second, it operates in Fast Forward mode. If the Switch detects more than 18 errors a second, it operates in Store and Forward mode until the number of errors returns to zero.

Intelligent Forwarding

Forward

state if the Forwarding Mode is set to Intelligent.

Unit Setup screen (3C16900A)

— Received packets are buff-

— The Switch monitors the amount

Fast Forward / Store and

This read-only field shows the forwarding

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Enable / Disable

PACE

This field allows you to enable or disable PACE (Priority Access Control Enabled) for all ports on the Switch. PACE allows multimedia traffic to be carried over standard Ethernet and Fast Ethernet LANs by providing two features:

■

Implicit Class of Service

■

Interactive Access

Interactive Access should only be enabled on ports that connect to a single endstation, switch, bridge or router. You should disable Interactive Access on a port if it is connected to a repeater. Also, Interactive Access should only be enabled at one end of the link.

For more information about disabling Interactive Access for a port, refer to “

Setting Up the Switch

Ports” on page 4-12.

VLAN Configuration Mode

Port / AutoSelect

This field allows you to specify how ports on the Switch are placed in VLANs:

■

Port

— The ports use Port VLAN Mode, which means that they are manually placed in the required VLAN. This is the default mode.

■

AutoSelect

— The ports use AutoSelect VLAN Mode, which means that they are automatically placed in the required VLAN by referring to a

VLAN Server database in 3Com’s Transcend Enterprise Manager software.

For more information, refer to “

Using AutoSelect

VLAN Mode” on page 5-3.

Bridging Mode

bone

This field allows you to set the bridging mode,

Forward To All / Forward To Back-

which controls how packets with unknown addresses are processed:

■

Forward To All

— The Switch forwards packets with an unknown address to all ports in the same VLAN as the source port. This setting should only be used if your network has less than 500 MAC addresses.

■

Forward To Backbone

— The Switch forwards packets with an unknown address to the backbone port defined for the VLAN of the source port. This is the default setting.

For more information about VLANs and backbone ports, refer to “

Virtual LANs (VLANs)” on page 5-1.

Setting Up the Switch Unit 4-11

SDB Ageing Time

This field allows you to specify the ageing time (hours:minutes) for all non-permanent entries in the Switch Database of the unit. You can set an ageing time in the range 0 minutes to 277 hours, with a default of 30 minutes. If you enter 0:00, ageing is turned off. For more information about ageing times, refer to “

Setting Up the

Switch Database (SDB)” on page 4-16.

Spanning Tree

Enable / Disable

This field allows you to enable or disable the Spanning Tree Protocol (STP) on the Switch. For more information about STP, refer to “

Spanning Tree Protocol” on page

5-12.

Duplex Mode

Ports / Full Duplex on all Ports

Half Duplex / Full Duplex on 100M

This field allows you to set the duplex mode of ports that have Unit Default specified in the Duplex Mode field of the Port Setup screen. The default setting is Half Duplex. For more information about Duplex Mode, refer to

Setting Up the Switch Ports” on page 4-12.

“

1 / 2 / 3 / ... 24 / 25 / 26

Backbone Port

(3C16900A)

1 / 2 / 3 /...12 / 13 / 14

(3C16901A) If the Bridging Mode field is set to Forward to Backbone, and all the ports on the Switch belong to VLAN 1 and use Port VLAN Mode, then this field allows you to specify a backbone port for the Switch. In all other situations, the field is not displayed.

For more information about VLANs, refer to “

Virtual LANs (VLANs)” on page 5-1. For more informa-

tion about backbone ports and their role in VLAN functionality, refer to “

Setting Up VLANs on the

Switch” on page 5-8.

Default RMON Host/Matrix

Enable / Disable

This field allows you to enable (start) Hosts and Matrix RMON sessions on the Default VLAN, or disable (stop) existing sessions if they are no longer required. The default setting for this field is Disable. For more information about RMON sessions, refer to

RMON” on page 5-22.

“

Plug-in Module Type

This read-only field displays the type of Plug-in Module fitted to the rear of the unit, or displays Not Fitted.

Transceiver Module Type

This read-only field shows the type of Transceiver Module fitted to the rear of the unit, or displays Not Fitted.

Power Supply

Internal / External

This read-only field displays External if the Switch is receiving power from a Redundant Power System. In all other cases, this field displays Internal.

On a new or initialized Switch, all ports belong to VLAN 1 and use Port VLAN Mode.

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Setting Up the Switch Ports

With the Switch Management screen displayed, choose the management level appropriate port, then select the SETUP button.

The Port Setup screen is displayed as shown in

Figure 4-11

If the port is an ATM OC-3c Module port, the ATM Port Setup screen is displayed. For more information, refer to the “SuperStack II Switch ATM OC-3c Module User Guide”.

The screen shows the following:

Port ID

you have chosen to set up.

Media Type

type of the link connected to this port.

Port Speed

and duplex mode of the link. HD indicates half duplex, FD indicates full duplex.

Port State

enable or disable the port. To prevent unauthorized access, we recommend that you disable any unused ports.

Link State

field shows the state of the link:

■

Present

■

Not Available

This read-only field shows the ID of the port

This read-only field shows the media

This read-only field shows the speed

Enable / Disable

Present / Not Available

— The port is operating normally

— The link has been lost

1000

Port

. Choose the

This field allows you to

This read-only

Figure 4-11

Lost Links

times the link has been lost since the Switch was last reset. If the number in this field is not zero, you should check your cables and replace any that may be damaged.

If the port is directly connected to an endstation, the Lost Links counter increments each time the endstation goes through a power-off/on cycle.

Intelligent Flow Management

This field allows you to enable or disable Intelligent Flow Management (IFM). IFM minimizes packet loss which can occur with conventional switches.

IFM should be disabled if the port is connected to a repeated segment where the traffic is mainly local to that segment. Refer to “

Chapter 1

Port Setup screen (10BASE-T port)

This read-only field shows the number of

Enable / Disable

Server Connections” in

Setting Up the Switch Ports 4-13

IFM is not available on a port which has full duplex enabled:

If the Duplex Mode field in this screen is set to

■

Full Duplex, the Intelligent Flow Management field is not displayed

In all other cases where the port has full duplex

■

enabled, IFM has no effect

Security

Enable / Disable

When Security is enabled, the port enters single address learning mode. The Switch removes all addresses currently stored in the Switch Database against the port. The Switch then learns the source address from the first packet it receives on the port since Security was enabled.

Once the first address is learnt, no other endstation is permitted to access the network through the port. If an endstation with a different address attempts to transmit packets onto the network through the port, the port is automatically disabled and a trap is generated. The port remains disabled until it is enabled from the Port Setup screen or via SNMP management.

A more comprehensive set of security features is available through SNMP network management.

Disable Interactive Access

Yes / N o

This field allows you to disable the Interactive Access feature of PACE (Priority Access Control Enabled) on the current port. You should disable Interactive Access on a port if:

The port is connected to a repeater

■

The port is connected to a device with Interac-

■

tive Access enabled

For more information about the Interactive Access feature, refer to “

page 4-9

VLT Mode

Setting Up the Switch Unit” on

Enable / Disable

This field allows you to specify whether the port is a VLT (Virtual LAN Trunk) port. A Virtual LAN Trunk (or VLT) is a Switch-to-Switch link which carries traffic for all the VLANs on each Switch. To create a VLT, the ports on both ends of the link must be VLT ports. For more information about VLTs, refer to “

VLANs and the

Switch” on page 5-3.

If the port uses AutoSelect VLAN Mode (refer to the VLAN Configuration Mode field), you cannot specify that the port is a VLT port.

Security is not available on backbone ports. If the port has been defined as a backbone port, the Security field is not displayed.

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Half Duplex / Full Duplex / Unit

This field allows you to specify the duplex

mode of the port:

■

Full Duplex

— Full duplex allows frames to be transmitted and received simultaneously and, in effect, doubles the potential throughput of a link. In addition, full duplex also supports 100BASE-FX cable runs of up to 2km. You should only enable full duplex on a point to point link between the Switch and another device with full duplex support.

Full duplex is not supported on the Transceiver Module port.

■

Half Duplex

— You should use half duplex if the port connects to a shared Ethernet or Fast Ethernet LAN segment, or if the device at the other end of a point-to-point link does not support full duplex.

■

Unit Default

— The duplex mode of the port is defined by the Duplex Mode field in the Unit Setup screen. This is the default setting.

VLAN Configuration Mode

Unit Default

This field allows you to specify how the

Port / AutoSelect /

port is placed in a VLAN:

■

Port

— The port uses Port VLAN Mode, which means that the port is manually placed in the required VLAN.

1000

■

AutoSelect

— The port uses AutoSelect VLAN Mode, which means that the port is automatically placed in the required VLAN by referring to a VLAN Server database in 3Com’s Transcend Enterprise Manager software.

■

Unit Default

— The port uses Port VLAN Mode or AutoSelect VLAN Mode depending on the contents of the VLAN Configuration Mode field in the Unit Setup screen. This is the default setting.

For more information, refer to “

Using AutoSelect

VLAN Mode” on page 5-3.

Broadcast Storm Control

The Switch automatically creates an alarm on each of its ports to monitor the level of broadcast traffic on each port. The Broadcast Storm Control fields allow you to specify thresholds for the level of broadcast traffic on a port, and specify an action to take place if the threshold is exceeded.

Rising Threshold%

This field allows you to specify the percentage of broadcast traffic on the current port which triggers the alarm for the port. The default is 20%.

Falling Threshold%

This field allows you to specify the percentage of broadcast traffic on the current port required to reset the alarm for the port. The falling threshold prevents the rising threshold events being triggered continuously. The default is 10%.

Setting Up the Switch Ports 4-15

Rising Action

disable port/notify / blip / blip port/notify

none / event / disable port /

Use this field to specify the action for the alarm to take when it reaches the rising threshold:

none

■

— no action takes place

event

— an SNMP trap is generated

disable port disable port/notify

— the port is disabled

— the port is disabled and an

SNMP trap is generated

blip

— the broadcast and multicast traffic on the

■

port is blocked for five seconds

blip port/notify

■

— the broadcast and multicast traffic on the port is blocked for five seconds, and an SNMP trap is generated

user defined

is displayed in the Rising Action field, an unrecognized action has been specified using a MIB browser. You cannot select this option.

none / event / enable /

Falling Action

event + enable

Use this field to specify the action for the alarm to take when it reaches the falling threshold:

none

■

— no action takes place

event

— an SNMP trap is generated

enable

— the port is enabled

event + enable

— the port is enabled and an

SNMP trap is generated

user defined

is displayed in the Rising Action field, an unrecognized action has been specified using a MIB browser. You cannot select this option.

You should be aware of the following points when using Broadcast Storm Control:

The Switch takes 5–7 seconds to recognize that a

■

broadcast storm is occurring. Broadcast Storm Control calculates the average

■

broadcast bandwidth over the previous 20-second interval. The average is based on four samples taken at 5-second intervals.

When the average value exceeds the rising

■

threshold value, the rising action is triggered. The action is not triggered again until the average broadcast bandwidth falls below the falling threshold level.

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1000

Setting Up the Switch Database (SDB)

The Switch maintains a database of device addresses that it receives on its ports. It uses the information in this database to decide whether a frame should be forwarded or filtered. The database holds up to a maximum of 500 entries; each entry consists of the MAC address of the device and an identifier for the port on which it was received.

If you have set up Traps for the Switch, notification that the database is becoming full is provided by two traps:

■

Database is 90% full

■

Database is 100% full

These traps indicate that the maximum number of devices which can be connected to the Switch has been reached. You cannot connect any more devices to the Switch. Additional devices can, however, be connected to the rest of the network.

Entries are added into the Switch Database in two ways:

■

The Switch can learn entries. That is, the unit updates the SDB with the source MAC address, and the port identifier on which the source MAC address is seen. Addresses are not learned on the backbone port. Learning is affected by security (refer to the description for the Security field on page 4-13

■

The system administrator can enter and update entries using a MIB browser, an SNMP Network Manager or the Switch Database screen described in the following sections.

There are three types of entries in the SDB:

■

Ageing entries

— Initially, all entries in the database are ageing entries. Entries in the database are removed (aged out) if, after a period of time (ageing time), the device has not transmitted. This prevents the database from becoming full with obsolete entries by ensuring that when a device is removed from the network, its entry is deleted from the database. Ageing entries are deleted from the database if the Switch is reset or a power-off/on cycle occurs. For more information about setting an ageing time, refer to “

ting Up the Switch Unit” on page 4-9.

■

Non-ageing entries

— If the ageing time is set to 0:00, all ageing entries in the database are defined as non-ageing entries. This means that they do not age, but they are still deleted if the Switch is reset or a power off/on cycle occurs. For more information about setting an ageing time, refer to “

Setting Up the Switch Unit” on page

4-9.

■

Permanent entries

— Permanent entries do not age, and they are retained in the database if the Switch is reset or a power-off/on cycle occurs.

Set-

The Database View

The Unit Database View screen, as shown in

Figure 4-12

, allows you to view and configure the

Switch Database.

To access the Unit Database View screen, display the Switch Management screen, choose the management level

Unit

The Unit Database View screen shows the following:

Setting Up the Switch Database (SDB) 4-17

, then select the SDB button.

Database Entries

This read-only field shows the number of entries currently in the SDB. The database holds a maximum of 500 addresses.

MAC Address

If you highlight an entry in the listbox and press [Return], this field shows the MAC address for the entry.

Port Number

If you highlight an entry in the list-

box, this field shows the port identifier for the entry.

Permanent

This field allows you to specify

Yes / No

that the current entry is permanent. Refer to the previous section “

Setting Up the Switch Database (SDB)” for a description of permanent and ageing

entries.

You cannot specify that the current entry is permanent if the port uses AutoSelect VLAN Mode. For more information about AutoSelect VLAN Mode, refer to “

Using AutoSelect VLAN Mode” on page

5-3.

Figure 4-12

A listbox containing three fields:

Port MAC Address

currently stored in the database.

Permanent

permanent, or No if this entry is ageing or non-ageing.

FIND

database. Refer to “

base” on page 4-18.

REFRESH

it displays the latest information.

Unit Database View screen

The port ID for the entry.

The MAC address for the port

Yes / N o

Shows

Yes

if this entry is

This button lets you locate an entry in the

Searching the Switch Data-

This button refreshes the database so that

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1000

INSERT

This button lets you insert an entry into the database. You cannot insert an entry for a port which uses AutoSelect VLAN Mode.

DELETE

This button allows you to delete entries from the database. You cannot delete an entry if it is associated with a port which uses AutoSelect VLAN Mode.

Searching the Switch Database

You can search the switch database in two ways: by MAC address or port number.

By MAC Address

To locate the port number against which a particular MAC address is entered in the SDB:

In the MAC Address field, type in the MAC address you are trying to locate.

Select FIND. The port ID is displayed in the Port Number field and the entry in the listbox is highlighted with an asterisk (*).

By Port

To locate the MAC addresses entered against a particular port ID in the SDB:

Clear the MAC Address field by moving into the field and pressing [Space].

In the Port Number field, enter the port ID for which you want MAC addresses displayed.

Select FIND. The listbox will show entries in the database for that port only.

Adding an Entry into the SDB

In the MAC Address field, type in the MAC address of the device.

In the Port field, type in the port identifier for this device.

Select whether the entry is permanent or not by specifying Yes or No in the Permanent field.

Select INSERT.

Deleting an Entry from the SDB

In the listbox, highlight the entry you want to delete and press [Return], or type the MAC address into the MAC Address field.

Select DELETE.

Specifying that an Entry is Permanent

In the listbox, highlight the entry you want to make permanent and press [Return], or type the MAC address into the MAC Address field.

In the Permanent field, specify Yes.

Select INSERT.

Setting Up Resilient Links

You can configure a Switch to provide resilient links to another device so that network disruption is minimized if a link fails. A main link and a standby link. You define a resilient link pair by specifying the main port and standby port at one end of the pair.

Figure 4-13

Resilient link pair

resilient link pair

consists of a

Setting Up Resilient Links 4-19

When setting up resilient links, you should note the following:

Up to 13 resilient link pairs can be configured on

■

a 24-port Switch 1000, and up to seven pairs can be configured on a 12-port Switch 1000.

Resilient links cannot be set up if Spanning Tree

■

(STP) is enabled on the Switch. Resilient Links can only be set up on fiber or

■

twisted pair links. The main and standby links in the same pair, however, can use any combination of these media.

A resilient link pair can only be set up if:

■

The ports belong to the same VLAN.

■

The ports have an identical security setting.

■

Neither of the ports forms part of another

■

resilient link pair.

If the main port is VLT (Virtual LAN Trunk) port,

■

the standby port must also be a VLT port.

Under normal network operating conditions, the main link carries your data. The Receive Idle signal of a fiber link or the Test Pulse on an Ethernet twisted pair link is continually monitored by the Switch. If a signal loss is detected, the Switch immediately enables the standby port so that it carries the data. In addition, the main port is disabled.

If a main link has a higher bandwidth than its standby link, traffic is automatically switched back to the main link provided no loss of link is detected for two minutes. Otherwise, you need to manually switch traffic back to the main link.

A resilient link pair must be defined at only one

■

end of the connection. You cannot disable any port that is part of a resil-

■

ient link pair.

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Configuring Resilient Links

With the Switch Management screen displayed, choose the port that will be set up as the main port in the resilient link pair, then select the RESILIENCE button.

The Port Resilience screen is displayed as shown in

Figure 4-14

. This screen allows you to setup, edit

and delete resilient link pairs.

The screen shows the following:

1000

Main Port ID

This read-only field shows the ID of

the main port.

Media Type

Twisted Pair / Fiber

This read-only field

shows the media type connected to the main port.

Link State

Available / Not Available / Not Present

This read-only field shows the connection state of the main port:

■

Available

■

Not Available

■

Not Present

— The port is operating normally

— The resilient link pair is disabled

— The port is not present in the cur-

rent hardware

Standby Port ID

This field shows the current standby port ID and allows you to enter a new port ID. The standby port must be in the same VLAN as the main port.

Media Type

Twisted Pair / Fiber

This read-only field

shows the standby port media type.

Figure 4-14

Link State

This read-only field shows the connection state of the standby port:

■

Available

■

Not Available

■

Not Present

rent hardware

Standby Links Available

ports that you can configure as standby.

Pair State

Not Available

operating state of the resilient link pair:

■

Active

operating normally with both main and standby port capable of carrying traffic.

Port Resilience screen

Available / Not Available / Not Present

— The port is operating normally

— The resilient link pair is disabled

— The port is not present in the cur-

This listbox shows the

Active / Both Failed / Unknown /

This read-only field shows the current

— The resilient link pair is enabled and

Setting Up Resilient Links 4-21

Both Failed

■

— Although the resilient link is correctly configured, both links have failed. This could be due to loose connections or cable damage.

Unknown

■

— The network configuration has changed and the resilient link pair no longer conforms to the rules.

Not Available

■

Active Port

— The resilient link pair is disabled.

Main / Standby

If a main link does

not

have a higher bandwidth than its standby link, traf-

not

fic is

automatically switched back to the main link when it recovers. Use this field to manually switch traffic back to the main link.

Pair Enable

Enabled / Disabled

Use this field to enable or disable the resilient link pair. Before you disable a resilient link pair, you must remove cabling from the ports to avoid creating loops in your network configuration.

Creating a Resilient Link Pair

Ensure that the port nominated as the standby port

is not physically connected to the unit. Ensure both ports have an identical port security

mode configuration and that they are members of the same VLAN.

At the Switch Management screen, select the port

to be configured as the main port in the link. Select the RESILIENCE button at the foot of the screen.

Select the standby port from the Standby Links

Available listbox or enter the port ID in the Standby Port ID field.

Enable the pair in the Pair Enabled field. Select

APPLY. Connect the cabling for the standby port.

Deleting a Resilient Link

To delete the resilient link set up on the port, select the DELETE button at the foot of the screen. The Port Resilience screen closes and the Switch Management screen is displayed.

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ANAGING THE SWITCH

Viewing the Resilient Setup

With the Switch Management screen displayed, choose the management level RESILIENCE button.

The Unit Resilience Summary screen is displayed as shown in Figure 4-15

. This screen shows the current resilient link configuration for the unit, and allows you to access the Port Resilience screen for resilient link pairs.

The following information is displayed:

1000

Unit

and select the

MAIN Port

This read-only field displays the ID of the port configured as the main port for the resilient link pair.

STANDBY Port

This read-only field displays the ID of the port configured as the standby port for the resilient link pair.

Pair State

Available

Active / Both Failed / Unknown / Not

This read-only field displays the current

state of the resilient link pair:

■

Active

— The resilient link pair is enabled and operating normally, with both main and standby ports capable of carrying traffic.

■

Both Failed

— Although the resilient link is correctly configured, both links have failed. Check for any loose connections or cable damage.

■

Unknown

— The network configuration has changed and the resilient link pair no longer conforms to the rules.

■

Not Available

— The resilient link pair is disabled.

Figure 4-15

Active Port

read-only field displays which port in the resilient link pair is currently carrying traffic:

■

Main

with the main port carrying traffic.

■

Standby

standby port is carrying the traffic. You should rectify the fault as soon as possible. If a main port has a higher bandwidth than the standby port, traffic will be automatically switched back provided no loss of link is detected for two minutes. Otherwise, set the Active Port setting in the Port Resilience screen (described on page

4-20) to Main to manually switch traffic back.

■

Both Failed

have failed. This could be due to loose connections or cable damage.

Unit Resilience Summary screen

Main / Standby / Both Failed

This

— The pair is operating in its normal state

— The main port has failed and the

— Both ports of the resilient link pair

Setting Up Resilient Links 4-23

Pair Enable

Enabled / Disabled

This read-only field displays whether the resilient link pair is currently enabled or disabled. You enable or disable a resilient link pair using the Port Resilience screen described in

Configuring Resilient Links” on page 4-20.

“

This button allows you to access the Port Resil-

ience screen for the current resilient link pair.

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Setting Up Traps

Traps are messages sent across the network to an SNMP Network Manager. They alert the network administrator to faults or changes at the Switch device.

Your Network Manager may automatically set up traps in the Switch Trap Table. Check the documentation accompanying your network management software.

ANAGING THE SWITCH

1000

To access the Trap Setup screen, select the SETUP TRAPS button from the Management Setup screen (described in Chapter 3 shown in Figure 4-16

). The Trap Setup screen is

The screen shows the following:

IP or IPX Address

This field allows you to enter the IP or IPX address of the remote network management stations to which traps should be sent.

Community String

This field allows you to enter community strings for each remote Network Manager, allowing a very simple method of authentication between the Switch and the remote Network Manager. The text string can be of 32 characters or less. If you want a Network Manager to receive traps generated by the device, you must enter the community string of the Network Manager into the trap table. The default community string is

public

Figure 4-16

Throttle

delay value for each remote Network Manager. Throttle delays are time periods placed between packets to prevent a remote Network Manager receiving too many traps at once. The unit of throttle is one thousandth of a second. The default value is 100, which gives a delay of one tenth of a second between each packet transmission.

Trap Setup screen

This field allows you to specify a throttle

Setting Up the Console Port

From the Switch Management Setup screen, described in Chapter 3 button. The Console Port Setup screen is displayed as shown in Figure 4-17

If you change any of the console port parameters, you terminate any existing sessions using the console port when you exit the screen. Ensure that the connected equipment’s console port parameters are set to match the new configuration. This allows you to continue to access the management facility from the equipment after you change the console port parameters.

The screen shows the following:

Connection Type

you to select the type of console port connection.

Remote

Select

if you want to manage the Switch through a modem; DCD Control and DSR Control are enabled. For all other cases, this field should be

Local

set to

DCD Control

Enabled / Disabled

applicable to local connection types. It determines if DCD is required for a local connection, and whether the connection is closed if DCD is removed. Refer to your terminal or modem user documentation if you are unsure of the correct setting.

, select the CONSOLE PORT

Local / Remote

This field allows

This field is only

Figure 4-17

DSR Control

applicable to local connection types. It determines if DSR is required for a local connection, and whether the connection is closed if DSR is removed. Refer to your terminal or modem user documentation if you are unsure of the correct setting.

Flow Control

RTS-CTS Unidirectional / RTS-CTS Bidirectional

This field allows you to select the correct flow control option for your terminal or modem. Refer to your terminal or modem documentation if you are unsure of the correct setting.

Auto Config

auto configure the line speed (baud rate) to work with your VT100 terminal. This field allows you to specify whether auto-configuration is enabled.

Setting Up the Console Port 4-25

Console Port Setup screen

Enabled / Disabled

XON/XOFF / NONE /

Enabled / Disabled

This field is only

The Switch can

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1000

Speed

1200 / 2400 / 4800 / 9600 / 19200

This field allows you to select the correct line speed (baud rate) for your terminal or modem. If you have enabled auto-configuration, line speed is set automatically.

Char Size

8 This read-only field shows the character bit (data bit) size for the Switch. You should set your terminal to the same value.

NONE

Parity

This read-only field shows the parity setting for the Switch. You should configure your terminal to the same setting.

Stop Bit

1 This read-only field shows the stop bit setting for the Switch. You should configure your terminal to the same setting.

Resetting the Switch

If you suspect a problem with the Switch, you can reset it.

From the Main Menu, select the RESET option.

The Reset screen is displayed as shown in

Figure 4-18

Select OK.

Resetting the Switch in this way is similar to performing a power-off/on cycle. No setup information is lost.

Figure 4-18

Resetting the Switch 4-27

Reset screen

CAUTION:

Performing a reset may cause some of the data being transmitted at that moment to be lost.

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ANAGING THE SWITCH

Initializing the Switch

This screen allows you to perform a reset as described in the previous section, and in addition, returns non-volatile data stored on the unit to its factory defaults (shown on page 1-14 the IP address is not cleared. You should only initialize the Switch if:

■

The configuration of the device no longer suits your network

■

Other efforts to solve problems have not succeeded

To initialize the Switch:

From the Main Menu, select the INITIALIZE option. The Initialize screen appears as shown in

Figure 4-19

Select OK.

CAUTION: Use the Initialize option with great care. The Switch configuration is cleared from memory and cannot be recovered. After initialization, all user information is lost and only default users are available. All ports are set to their default values, and are therefore enabled and available to all users.

1000

). Note that

Figure 4-19

■

VLT ports fail and you are not able to manage the Switch if your management station communicates via the VLT. To avoid this:

Remove the VLT configuration from both ends of the VLT link before you initialize the Switch. Note that the port furthest from your management station should have its VLT configuration removed first.

Reconfigure the VLT once the initialization is complete.

Initialize screen

When initializing the Switch, take particular note of the following:

■

Network loops occur if you have set up resilient links. Before initializing the Switch, ensure you have disconnected the cabling for all your standby links.

Upgrading Software

When 3Com issues a new version of agent software for the Switch, you can obtain it from the 3Com’s information delivery systems described in “

Technical Services” on page F-1.

For upgrading the ATM OC-3c Module software, refer to the “SuperStack II Switch ATM OC-3c Module User Guide”.

You use the Software Upgrade screen to download new software images. The protocol used for downloading software images is TFTP running over UDP/IP or IPX.

CAUTION:

the following:

The download only works over the network; it

■

does not work through the console port. The download does not work over a Virtual LAN

■

Trunk (VLT) if you have a Boot software version lower than version 2.0.

The download does not work over an ATM link.

■

If a software download over IPX fails, enter the MAC or Ethernet address of your server into the Switch Database via the Unit Database View screen and then attempt the download again. Refer to

Searching the Switch Database” on page 4-18.

“

Before attempting to download, note

Online

Figure 4-20

To upgrade Switch management software: From the Main Menu, select the SOFTWARE

UPGRADE option. The Software Upgrade screen is displayed, as

shown in Figure 4-20 From the Destination field, select Switch (this is the

default). In the File Name field, enter the name of the file

that contains the software image to be downloaded to the Switch.

You must place the image file where it is accessible to the TFTP load request. Check with your system administrator if you are unsure of where to place the image file.

In the Server Address field, enter the IP or IPX

address of the server containing the software image to be loaded.

Upgrading Software 4-29

Software Upgrade screen

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ANAGING THE SWITCH

1000

During the download, the MGMT LED flashes green and the screen is locked. When the download is complete, the Switch is reset.

DVANCED

Virtual LANs (VLANs)

Setting up Virtual Local Area Networks (VLANs) on the Switch 1000 provides you with less timeconsuming network administration and more efficient network operation.

ANAGEMENT

With VLANs, you can define your network according to:

■

Departmental groups

have one VLAN for the Marketing department, another for the Finance department, and another for the Development department.

— For example, you can

The following sections explain more about the concept of VLANs and explain how they can be implemented on the Switch 1000.

What are VLANs?

A VLAN is defined as a group of location- and topology-independent devices that communicate as if they are on the same physical LAN. This means that LAN segments are not restricted by the hardware which physically connects them; the segments are defined by flexible user groups that you create using software.

■

Hierarchical groups

have one VLAN for directors, another for managers, and another for general staff.

■

Usage Groups

one VLAN for users of e-mail, and another for users of multimedia.

Benefits of VLANs

Implementing VLANs on your network has three main advantages:

It eases the change and movement of devices on

■

IP networks It helps to control broadcast traffic

■

It provides extra security

■

— For example, you can

— For example, you can have

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How VLANs Ease Change and Movement

With traditional IP networks, network administrators spend much of their time dealing with moves and changes. If users move to a different IP subnet, the IP addresses of each endstation must be updated manually.

With a VLAN setup, if an endstation in VLAN 1 is moved to a port in another part of the network, you only need to specify that the new port is in VLAN 1. This is something that can be done auto-

matically if you have 3Com’s Transcend

Enterprise

Manager for Windows (v6.0 and above).

How VLANs Control Broadcast Traffic

With traditional networks, congestion can be caused by broadcast traffic which is directed to all network devices whether they require it or not. VLANs increase the efficiency of your network because each VLAN can be set up to contain only those devices which need to communicate with each other.

How VLANs Provide Extra Security

An Example

Figure 5-1 shows a network configured with three

VLANs — one for each of the departments who access the network. The membership of VLAN 1 is restricted to ports 1, 2, 3, 4 and 5 of Switch A; membership of VLAN 2 is restricted to ports 4, 5, 6, 7 and 8 of Switch B while VLAN 3 spans both Switches containing ports 6, 7, 8 of Switch A and 1, 2, 3 of Switch B.

In this simple example, each of these VLANs can be seen as a ments that are not constrained by their physical location.

Specific configurations using the Switch are shown later in this chapter.

broadcast domain

— physical LAN seg-

Devices within each VLAN can only communicate with devices in the same VLAN. If a device in VLAN 1 needs to communicate with devices in VLAN 2, the traffic must cross a router.

Figure 5-1

The concept of VLANs

Virtual LANs (VLANs) 5-3

VLANs and the Switch

The Switch 1000 supports VLANs which consist of a set of switch ports. Each switch port can only belong to one VLAN at a time, regardless of the device to which it is attached.

Each Switch 1000 can support up to 16 VLANs. However, you can have more than 16 VLANs in your entire network by connecting the 16 Switch VLANs to other VLANs using a router.

The Default VLAN and Moving Ports From the Default VLAN

On each Switch, VLAN 1 is the Default VLAN of the Switch; it has two properties:

It contains all the ports on a new or initialized

■

Switch It is the only VLAN which allows an SNMP Net-

■

work Manager to access the management agent of the unit

By default, if a device is attached to a port in the Default VLAN and you want to move the device into another VLAN, you need to use the VLAN Setup screen to place the port in that VLAN. For more information about the VLAN Setup screen, refer to

Setting Up VLANs on the Switch” on page 5-8.

“

Connecting VLANs to a Router

If the devices in a VLAN need to talk to devices in a different VLAN, each VLAN requires a connection to a router. Communication between VLANs can only take place if they are all connected to the router. A

VLAN not connected to a router is an isolated VLAN. You need one port for each VLAN connected to the router.

Connecting Common VLANs Between Switch Units

If you want to connect the VLANs on the Switch 1000 with the same VLANs on another Switch unit, you can set up one link per VLAN. Alternatively, you can set up a single link for all the VLANs by creating a

Virtual LAN Trunk

(VLT). A VLT is a Switch-to-Switch link which carries traffic for all the VLANs on each Switch. To set up a VLT, you configure the port at each end of the link.

VLTs can only be used for links between Super-

II Switch 1000, Switch 3000 and Desktop

Stack Switch units. You cannot use VLTs for Switch–router links.

If you specify that a port on one VLAN is a VLT port, that port carries traffic for all the VLANs on the Switch. If you then disable the VLT function on that port, the port only carries traffic for the Default VLAN (VLAN 1).

Using AutoSelect VLAN Mode

By default, all ports on the Switch use Port VLAN Mode — where each switch port is

manually

placed in the required VLAN. The Switch allows some ports to use another mode, AutoSelect VLAN Mode. In this mode, the ports are

automatically

placed in the required VLAN by referring to a VLAN Server database in 3Com’s Transcend Enterprise Manager v6.0 for Windows.

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AutoSelect VLAN Mode works as follows:

When an endstation is connected to a Switch or moves from one port to another, the Switch learns the MAC address of the endstation.

Figure 5-2

If the relevant port uses AutoSelect VLAN Mode, the

Switch learns the endstation’s MAC address

Switch interrogates the VLAN Server to determine the VLAN membership of the endstation.

Figure 5-3

Having obtained the VLAN membership for the end-

Switch interrogates the VLAN Server

station, the Switch places the relevant port in the specified VLAN.

Figure 5-4

Switch places the port in the VLAN

AutoSelect VLAN Mode has an advantage over Port VLAN Mode because once the VLAN Server database is set up correctly, you can move endstations to other ports or other Switch units and the VLAN allocation of each endstation is automatically configured.

If you use AutoSelect VLAN Mode, note the following:

■

You need to specify an IP address and community string for the VLAN Server.

■

You cannot use VLAN 15.

■

If a port has been configured as a backbone port or as a VLT port, the port cannot use AutoSelect VLAN Mode.

■

If a port has a permanent address stored against it in the Switch Database, the port cannot use AutoSelect VLAN Mode.

■

We recommend that you connect each switch port to a single endstation. If you want to connect a port to multiple endstations, specify that the port uses Port VLAN Mode.

Virtual LANs (VLANs) 5-5

For information about how to set up VLANs using AutoSelect VLAN Mode, refer to Chapter 5

page 5-11

For more information about the VLAN Server database, refer to the documentation supplied with 3Com’s Transcend Enterprise Manager.

Using Non-routable Protocols

If you are running non-routable protocols on your network (for example, DEC LAT or NET BIOS), devices within one VLAN are not able to communicate with devices in a different VLAN.

Using Unique MAC Addresses

If you connect a server with multiple network adapters to the Switch, we recommend that you configure each network adapter with a unique MAC address.

Extending VLANs into an ATM Network

If the Switch has an ATM OC-3c Module installed, you can extend the VLANs you have defined in your existing network into an ATM network. For more information, refer to the “

Switch ATM OC-3c Module User Guide”

SuperStack II

Example 1

The example shown in Figure 5-5

illustrates a simple VLAN configuration with a single Switch 1000 whose ports are divided between two VLANs. VLAN 1 is able to talk to VLAN 2 using the connection between each VLAN and the router.

To set up this configuration: Use the VT100 screens or VLAN Server database to:

Place ports 1–6 and 13–18 in VLAN 1.

Place ports 7–12 and 19–24 in VLAN 2.

Connect a port in VLAN 1 to the router.

Connect a port in VLAN 2 to the router.

VLAN Configurations

You can set up VLAN configurations more easily if you use 3Com’s Transcend Enterprise Manager applications for all the management tasks.

Figure 5-5

VLAN configuration with a single Switch 1000 unit

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The example shown in Figure 5-6

illustrates two VLANs spanning two Switch 1000 units. VLAN 1 is able to talk to VLAN 2 using the connection between each VLAN and the router. Ports within the same VLAN but on different Switches communicate using the VLT.

To set up this configuration:

Use the VT100 screens or VLAN Server database to:

Place ports 1–6 and 13–18 of both Switch units in VLAN 1.

Place ports 7–12 and 19–24 of both Switch units in VLAN 2.

Connect port 26 of the higher Switch to Server 1.

Connect port 26 of the lower Switch to Server 2.

Use the VT100 screens or VLAN Server database to:

Place port 26 of the higher Switch in VLAN 2.

Place port 26 of the lower Switch in VLAN 1.

Connect a port on the higher Switch to a port in the lower Switch.

Use the VT100 screens to specify that the Switch-to-Switch port on the higher Switch is a backbone port and a VLT port.

Use the VT100 screens to specify that the Switch-to-Switch port on the lower Switch is a VLT port.

Figure 5-6

Connect a VLAN 1 port on the lower Switch to the router.

Connect a VLAN 2 port on the lower Switch to the router.

VLAN configuration with two Switch 1000 units

Example 3

The example shown in Figure 5-7

illustrates two VLANs spanning three Switch 1000 units and a basement Switch 3000 FX with a Plug-in Module. Each Switch 1000 connects into the basement Switch using a VLT. The attached router allows the two VLANs to communicate with each other.

To set up this configuration: Use the VT100 screens or VLAN Server database to:

Place ports 1–6 and 13–18 of all the Switch 1000

units in VLAN 1. Place ports 7–12 and 19–24 of all the Switch

1000 units in VLAN 2.

Connect a port on each Switch 1000 to a port in

the Switch 3000 FX. Use the VT100 screens to:

Specify that each Switch 1000 port connected to

the Switch 3000 FX is a backbone port.

Virtual LANs (VLANs) 5-7

Specify that each Switch 1000 port connected to

the Switch 3000 FX is a VLT port. Specify that each Switch 3000 FX port con-

nected to a Switch 1000 is a VLT port.

Connect port 1 of the Switch 3000 FX to Server 1.

Connect port 2 of the Switch 3000 FX to Server 2.

Use the VT100 screens or VLAN Server database to:

Place port 1 of the Switch 3000 FX in VLAN 1.

Place port 2 of the Switch 3000 FX in VLAN 2.

Figure 5-7

Connect two spare ports on the Switch 3000 FX to

the router. Use the VT100 screens or VLAN Server database to

specify that one Switch 3000 FX port connected to the router is placed in VLAN 1, and the other is placed in VLAN 2.

VLAN configuration with a basement Switch 3000 FX

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Setting Up VLANs on the Switch

The VLAN Setup screen allows you to:

■

Assign ports to VLANs, if those ports use Port VLAN Mode

■

Define a backbone port for each VLAN

■

View VLAN setup information for the Switch

To access the VLAN Setup screen:

From the Main Menu, select SWITCH MANAGEMENT. The Switch Management screen is displayed.

In the Management Level field, choose

Choose the SETUP button. The VLAN Setup screen is displayed, as shown in Figure 5-8

The screen shows the following:

VLAN

Figure 5-8

VLAN Setup screen

— The port is the backbone port for the

■

VLAN(s) specified in the VLAN Membership field.

A listbox containing three fields:

This field allows you to select the ID of the

Port

port that you want to set up.

VLT / Bp / Standby / ATM / AutoSelect

Typ e

This field displays information about the setup of the port:

VLT

— The port is a VLT port. A Virtual LAN

■

Trunk (or VLT) is a Switch-to-Switch link which carries traffic for all the VLANs on each Switch. For more information about VLTs in general, refer to “

page 5-3

. To specify that a port is a VLT port, refer to “Setting Up the Switch Ports”

page 4-12

VLANs and the Switch” on

A backbone port is used to connect each VLAN to the backbone of your network. Addresses received on the port are not stored in the Switch Database. Frames with unknown addresses received by the Switch are forwarded to the port

Standby

■

— The port is the standby port of a resilient link pair. The main port of the pair is displayed in brackets. For more information about resilient links, refer to “Setting Up Resil-

ient Links” on page 4-19.

ATM

■

— The port is an ATM OC-3c Module

port. For more information, refer to the

SuperStack II Switch ATM OC-3c Module User

“

Guide”

Virtual LANs (VLANs) 5-9

AutoSelect

■

— The port uses AutoSelect VLAN Mode. For more information about AutoSelect VLAN Mode, refer to “

Using AutoSelect VLAN Mode” on page 5-3. For information

about how to configure VLANs using AutoSelect VLAN Mode, refer to “

Setting Up VLANs Using AutoSelect VLAN Mode” on page 5-11.

VLAN Membership

This field displays the ID of

the VLAN(s) to which the port belongs.

Port ID

1 / 2 / 3 /... 12 / 13 / 14 (3C16901A)

1 / 2 / 3 / ... 24 / 25 / 26 (3C16900A)

This field displays the ID of the port currently selected in the listbox.

VLAN ID

1 / 2 / 3 / ... 16

If the port specified in the Port ID field uses Port VLAN Mode, this field allows you to enter the ID of the VLAN to which the port is to be assigned. If the port uses AutoSelect VLAN Mode, you cannot specify the VLAN ID. By default, all ports use Port VLAN Mode and belong to the Default VLAN (VLAN 1). This field is not displayed if the port is a VLT port.

If you are using AutoSelect VLAN Mode, you cannot use VLAN 15. Also, if you are using the Spanning Tree Protocol, you cannot use VLAN 16. In these cases, the relevant VLANs are used internally by the Switch and are therefore not available.

Backbone Port

Yes / No

If the port specified in the Port ID field uses Port VLAN Mode, this field allows you to specify whether the port is a backbone port. If the port uses AutoSelect VLAN Mode or is the standby port of a resilient link pair, you cannot specify that it is a backbone port.

Each VLAN can have one backbone port. By default, all ports belong to the Default VLAN (VLAN 1); because of this, an unconfigured Switch unit can only have one backbone port.

If you specify that an ATM OC-3c Module port is a backbone port, the port becomes a backbone port for all the VLANs on which it is active. It cannot be the backbone port for one VLAN and a standard port for another.

If you fit a Plug-in Module into a Switch with no specified backbone ports, the Module automatically becomes the backbone port for the Default VLAN when you power up or initialize the Switch. If a Switch has no Plug-in Module, but you fit a Transceiver Module, this becomes the backbone port for the Default VLAN when you power up or initialize the Switch.

APPLY

This button applies any changes to the VLAN

database.

ATM LEC Setup

If the port is an ATM OC-3c Module port, this button allows you access the VLAN LEC Setup screen for extending your VLANs into an ATM network. For more information, refer to the “

User Guide”

SuperStack II Switch ATM OC-3c Module

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Assigning a Port to a VLAN When Using Port VLAN Mode

In the Port ID field, enter the ID of the required port.

In the VLAN ID field, enter the ID of the required VLAN.

Select APPLY.

CAUTION: Initially, all Switch ports belong to the Default VLAN (VLAN 1). This VLAN is the only one that allows an SNMP Network Manager to access the management agent of the unit. If you remove all ports from VLAN 1, then an SNMP Network Manager cannot manage the Switch.

Specifying a Backbone Port

In the Port ID field, type the ID of the required port.

In the VLAN ID field, type the ID of the required VLAN.

In the Select Port Type field, select Backbone Port.

Select APPLY.

Specifying that a Port is a VLT Port

To specify that a port is a VLT port, refer to “Set-

ting Up the Switch Ports” on page 4-12.

To create a VLT link, the ports on both ends of the link must be VLT ports.

Setting Up VLANs Using AutoSelect VLAN Mode

To set up VLANs using AutoSelect VLAN Mode, you need to:

Specify information about the VLAN Server

■

Specify that the Switch unit, or individual ports

■

on the unit, use AutoSelect VLAN Mode

Specifying Information About the VLAN Server

The VLAN Server screen allows you to specify information about the VLAN Server. To access the VLAN Server screen:

From the Main Menu, select SWITCH MANAGE-

MENT. The Switch Management screen is displayed. In the Management Level field, choose VLAN.

Choose the SERVER button. The VLAN Server

screen is displayed, as shown in Figure 5-9

The screen shows the following:

Figure 5-9

Throttle

the time delay, in milliseconds, between the transmission of VLAN allocation requests to the Server. The time delay is used to avoid placing an excessive workload on the VLAN Server. The default setting for this field is 50 milliseconds.

VLAN Server screen

0...99999

Virtual LANs (VLANs) 5-11

This field allows you to specify

VLAN Server IP Address

Enter the IP address of

your VLAN Server in this field.

Backup VLAN Server IP Address

This field allows you to enter the IP address of a backup VLAN Server. A backup VLAN Server can be used to supply VLAN allocations when the Switch cannot access the main VLAN Server.

VLAN Server Community String

This field allows you to enter a community string for the VLAN Server(s). The default community string is

public

Poll Period

This read-only field shows the time interval, in seconds, between successive polls of the VLAN Server. The Switch polls the VLAN Server once every poll period to check for any changes.

Specifying AutoSelect VLAN Mode

To specify that the Switch uses AutoSelect VLAN Mode, refer to “Setting Up the Switch Unit”

page 4-9

To specify that a port on the Switch uses AutoSelect VLAN Mode, refer to “Setting Up the

Switch Ports” on page 4-12.

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Spanning Tree Protocol

Using the Spanning Tree Protocol (STP) functionality of your Switch makes your network more fault tolerant.

The following sections explain more about STP and the STP features supported by the Switch.

STP is not currently supported over an Asynchronous Transfer Mode (ATM) network. Therefore, if you have an ATM OC-3c Module installed in your Switch, it does not join the STP system.

What is STP?

STP is a part of the 802.1d bridge specification defined by the IEEE Computer Society. To explain STP more effectively, the Switch 1000 will be defined as a bridge.

work to overload; however, STP allows you to have this configuration because it detects duplicate paths and immediately prevents, or

blocks

, one of them

from forwarding traffic.

Figure 5-11

shows the result of enabling STP on the bridges in the configuration. The STP system has decided that traffic from LAN segment 2 to LAN segment 1 can only flow through Bridges C and A.

If the link through Bridge C fails, as shown in

Figure 5-12

, the STP system reconfigures the network so that traffic from segment 2 flows through Bridge B.

STP is a bridge-based system for providing fault tolerance on networks. STP allows you to implement parallel paths for network traffic, and ensure that:

■

Redundant paths are disabled when the main paths are operational

■

Redundant paths are enabled if the main paths fail

As an example, Figure 5-10

shows a network containing three LAN segments separated by three bridges. With this configuration, each segment can communicate with the others using two paths. This configuration creates loops which cause the net-

Spanning Tree Protocol 5-13

Figure 5-10

Figure 5-11

A network configuration that creates loops.

Traffic flowing through Bridges C and A

Figure 5-12

Traffic flowing through Bridge B

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How STP Works

STP Initialization

Initially, the STP system requires the following before it can configure the network:

■

Communication between all the bridges. This communication is carried out using Bridge Protocol Data Units (BPDUs), which are transmitted in packets with a known multicast address.

■

One bridge to start as a master or Root Bridge, a central point from which the network is configured.

The Root Bridge is selected on the basis of it having the lowest Bridge Identifier value. This is a combination of the unique MAC address of the bridge and a priority component defined for the bridge.

The Root Bridge generates BPDUs on all ports at a regular interval known as the Hello Time. All other bridges in the network have a Root Port. This is the port nearest to the Root Bridge, and it is used for receiving the BPDUs initiated by the Root Bridge.

STP Stabilization

Once the network has stabilized, two rules apply to the network:

Each network segment has one Designated Bridge Port. All traffic destined to pass in the direction of or through the Root Bridge flows through this port. The Designated Bridge Port is the port which has the lowest Root Path Cost for the segment.

The Root Path Cost consists of the path cost of the Root Port of the bridge, plus the path costs across all the Root Ports back to the Root Bridge.

Tab le 5- 1

shows the default path costs for the

Switch 1000.

Table 5-1

Port Type Duplex Cost

100BASE-TX / 100BASE-FX (VLT) Full 5

10BASE-T (VLT) Full 24

100BASE-TX / 100BASE-FX Full 150

10BASE-T Full 650

Default path costs

Half 12

Half 25

Half 300

Half 700

After all the bridges on the network have determined the configuration of their ports, each bridge only forwards traffic between the Root Port and the ports that are the Designated Bridge Ports for each network segment. All other ports are

blocked

which means that they are prevented from forwarding traffic.

STP Reconfiguration

In the event of a network failure, such as a segment going down, the STP system reconfigures the network to cater for the changes. If the topology of your network changes, the first bridge to detect the change

sends out an SNMP trap.

An Example

Figure 5-13

illustrates part of a network. All bridges have a path cost value assigned to each port, identified by PC=xxx (where xxx is the value).

Bridge A is selected by STP as the Root Bridge, because it has the lowest Bridge Identifier. The Designated Bridge Port for LAN A is port 1 on Bridge A. Each of the other four bridges have a Root Port (the port closest to the Root Bridge). Bridge X and Bridge B can offer the same path cost to LAN B. In this case Bridge B's port is chosen as the Designated Bridge Port, because it has the lowest Bridge Identifier. Bridge C's port is chosen as the Designated Bridge Port for LAN C because it offers the lowest Root Path Cost (the route through Bridge C and B costs 200, the route through Bridge Y and B would cost 300). You can set the path cost of a bridge port to influence the configuration of a network with a duplicate path.

Once the network topology is stable, all the bridges listen for special Hello BPDUs transmitted from the Root Bridge at regular intervals. If the STP Max Age time expires (refer to “

Configuring the STP Parameters of VLANs” on page 5-18) before receiving a

Hello BPDU, it assumes that the Root Bridge, or a link between itself and the Root Bridge, has gone down. It then initiates a reconfiguration of the network topology.

Spanning Tree Protocol 5-15

You can adjust timers to determine how quickly a network reconfigures and therefore how rapidly the network recovers from a path failure (refer to “

Configuring the STP Parameters of VLANs” on page 5-18).

Figure 5-13

Port costs in a network

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STP Configurations

Figure 5-14 shows two possible STP configurations

using SuperStack II Switch units:

■

Configuration 1 — Redundancy for Backbone Link

In this configuration, a Switch 1000 and Switch 3000 TX both have STP enabled and are connected by two Fast Ethernet links. STP discovers a duplicate path and disables one of the links. If the enabled link breaks, the disabled link becomes re-enabled, therefore maintaining connectivity.

■

Configuration 2 — Redundancy through Meshed Backbone

In this configuration, four Switch 3000 TX units are connected such that there are multiple paths between each one. STP discovers the duplicate paths and disables two of the links. If an enabled link breaks, one of the disabled links becomes re-enabled, therefore maintaining connectivity.

DVANCED MANAGEMENT

Figure 5-14

STP configurations

Enabling STP on the Switch

To enable STP on your Switch: From the VT100 Main Menu, select SWITCH MAN-

AGEMENT. The Switch Management screen is displayed.

In the Management Level field, choose Unit.

Choose the SETUP button. The Unit Setup screen is

displayed, as shown in Figure 5-15 In the Spanning Tree field, specify Enable.

Choose OK.

You cannot enable STP if you have set up resilient links on any of the Switch ports, or if you are using VLAN 16.

Spanning Tree Protocol 5-17

Figure 5-15

Unit Setup screen

CAUTION:

If STP is enabled on your Switch 1000 and the Switch is connected to another Switch 1000, a Desktop Switch, or a repeater, the Bridging Mode of the Switch must be set to Forward to All. If the Bridging Mode of the Switch 1000 is set to Forward to Backbone, link losses may occur on your network. For more information about setting the Bridging Mode for your Switch, refer to “Setting

Up the Switch Unit” on page 4-9.

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Configuring STP on the Switch

CAUTION: You should not configure any STP parameters unless you have considerable knowledge and experience with STP.

Configuring the STP Parameters of VLANs

The Switch has a completely separate STP system for each VLAN that you have specified. Each VLAN has its own Root Bridge, Root Ports and BPDUs.

The VLAN STP screen allows you to set up and manage an STP system for each VLAN on the Switch. To access the VLAN STP screen:

From the Main Menu, select SWITCH MANAGEMENT. The Switch Management screen is displayed.

In the Management Level field, choose VLAN.

Choose the STP button. The VLAN STP screen is displayed, as shown in Figure 5-16

The VLAN STP screen shows the following:

VLAN ID

1 / 2 / 3 / ... 15

This field allows you to

specify the VLAN to be configured.

If you are using STP, you cannot use VLAN 16. Also, if you are using AutoSelect VLAN Mode, you cannot use VLAN 15. In these cases, the relevant VLANs are used internally by the Switch and are therefore not available.

Figure 5-16

VLAN STP screen

Max Age

6...40

This read-only field shows the time (in seconds) that the Switch waits before trying to re-configure the network. If the Switch has not received a BPDU within the time specified in this

field, it will try to re-configure the network topology.

Designated Root

This read-only field shows the

Bridge Identifier of the designated Root Bridge.

1...10

Hello Time

This read-only field shows the time delay, in seconds, between the transmission of BPDUs from the Switch.

Root Cost

This read-only field shows the path cost

from the Switch to the Root Bridge.

Topology Changes

This read-only field shows the number of network topology changes that have occurred in the current VLAN.

4...30

Forward Delay

This read-only field shows the time (in seconds) that the ports on the Switch spend in the listening and learning states. For more information about these states, refer to “

Configur-

ing the STP Parameters of Ports” on page 5-20.

Root Port

This read-only field shows the Root Port

of the Switch.

Hold Time

This read-only field shows the shortest time interval (in seconds) allowed between the transmission of BPDUs.

Time Since Topology Change

This read-only field shows the time interval since the last topology change was detected.

Bridge Priority

0...65535

This field allows you to specify the priority of the Switch. By changing the priority of the Switch, you can make it more or less likely to become the Root Bridge. The lower the number, the more likely it is that the bridge will be the Root Bridge. The default setting for this field is

65535.

Spanning Tree Protocol 5-19

The time must be greater than, or equal to, 2 x (Hello Time + 1) and less than, or equal to, 2 x (Forward Delay – 1).

1...10

Bridge Hello Time

This field allows you to specify the time delay, in seconds, between the transmission of BPDUs from the Switch when it is the Root Bridge. The default setting for this field is 2 seconds.

4...30

Bridge Forward Delay

This field allows you to specify the time (in seconds) that the ports on the Switch spend in the listening and learning states when the Switch is the Root Bridge. The default setting is 15 seconds. For more information about these states, refer to “

Configuring the STP Parame-

ters of Ports” on page 5-20.

This button applies any changes to the STP

APPLY

system.

Do not change the priority of the Switch unless absolutely necessary.

6...40

Bridge Max Age

This field allows you to specify the time (in seconds) that the Switch waits before trying to re-configure the network when it is the Root Bridge. If the Switch has not received a BPDU within the time specified in this field, it will try to re-configure the STP topology. The default setting for this field is 20 seconds.

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Configuring the STP Parameters of Ports

The Port STP screen allows you to set up and manage the STP parameters of each port on the Switch. To access the Port STP screen:

From the Main Menu, select SWITCH MANAGEMENT. The Switch Management screen is displayed.

In the Management Level field, choose Port.

In the Port ID field, enter the ID of the port to be configured.

Choose the STP button. The Port STP screen is displayed, as shown in Figure 5-17

The screen shows the following:

Port ID

1 / 2 / 3 / ... 24 / 25 / 26 (3C16900A)

1 / 2 / 3 / ... 12 / 13 / 14 (3C16901A)

This read-only field shows the ID of the port to be configured.

STP State

/ Forwarding

Disabled / Listening / Blocking / Learning

This read-only field shows the current

state of the port:

■

Disabled

— A port in this state does not forward packets, and does not participate in STP operation.

■

Listening

— A port in this state is preparing to forward packets, but has temporarily blocked to prevent a loop. During the Listening state, BPDUs are transmitted, received and processed.

Figure 5-17

■

Blocking

packets to prevent more than one active path existing on the network. The port is included in STP calculations, and BPDUs can be transmitted, received and processed.

■

Learning

forward packets, but has temporarily blocked to prevent a loop. During the Learning state, the Switch learns the addresses of all error-free packets. The port is included in STP calculations, and BPDUs can be transmitted, received and processed.

■

Forwarding

packets. BPDUs can also be received and processed.

Designated Port

of the Designated Bridge Port for the current port’s segment.

Port STP screen

— A port in this state does not forward

— A port in this state is preparing to

— A port in this state can forward

This read-only field shows the ID

Spanning Tree Protocol 5-21

Designated Root

This read-only field shows the

Bridge Identifier of the Root Bridge.

Designated Cost

This read-only field shows the path cost from the Root Bridge to the Designated Bridge Port for the current port’s segment.

Designated Bridge

This read-only field shows the Bridge Identifier of the Designated Bridge for the current port’s segment.

Fwd Transitions

This read-only field shows the number of times that the current port has transitioned from the Learning state to the Forwarding state.

Port Enable

Enable / Disable

This field allows you

to enable or disable the current port.

0...255

Priority

This field allows you to specify the priority of the port. By changing the priority of the port, you can make it more or less likely to become the Root Port. The lower the number, the more likely it is that the port will be the Root Port. The default setting for this field is 128.

Fast Start

Enable / Disable

This field allows you to specify whether the port goes directly to the Forwarding state when a device is connected to it. Set this field to Enable if the port is directly connected to an endstation. The default setting for this field is Disable.

CAUTION:

If you set the Fast Start field to Enable when the port is connected to multiple endstations, loops may occur in your network.

Path Cost

0...65535

This field allows you to specify

the path cost of the port.

The Switch automatically assigns the default path costs shown in Ta bl e 5- 1

on page 5-14. If you specify a new path cost in this field, this automatic system is disabled, and you can only re-enable it by initializing the Switch.

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RMON

Using the RMON (Remote Monitoring) capabilities of your Switch allows network administrators to improve their efficiency and reduce the load on their network.

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What is RMON?

RMON is the common abbreviation for the Remote Monitoring MIB (Management Information Base), a system defined by the IETF documents RFC 1271 and RFC 1757, which allows you to monitor LANs remotely.

The following sections explain more about the RMON concept and the RMON features supported by the Switch.

You can only use the RMON features of the Switch if you have an RMON management application, such as the RMON application supplied with 3Com’s Transcend Enterprise Manager.

A typical RMON setup consists of two components:

■

The RMON probe

— An intelligent, remotely-controlled device or software agent that continually collects statistics about a LAN segment or VLAN, and transfers the information to a management workstation on request or when a pre-defined threshold is crossed.

■

The management workstation

— Communicates with the RMON probe and collects the statistics from it. The workstation does not have to be on the same network as the probe and can manage the probe by in-band or out-of-band connections.

RMON 5-23

About the RMON Groups

The IETF define nine groups of Ethernet RMON statistics. This section describes these groups, and details how they can be used.

Statistics

The Statistics group provides traffic and error statistics showing packets, bytes, broadcasts, multicasts and errors on a LAN segment or VLAN.

Information from the Statistics group is used to detect changes in traffic and error patterns in critical areas of your network.

History

The History group provides historical views of network performance by taking periodic samples of the counters supplied by the Statistics group. The group features user-defined sample intervals and bucket counters for complete customization of trend analysis.

The group is useful for analysis of traffic patterns and trends on a LAN segment or VLAN, and to establish baseline information indicating normal operating parameters.

Alarms

The Alarms group provides a versatile, general mechanism for setting thresholds and sampling intervals to generate events on any RMON variable. Both rising and falling thresholds are supported, and thresholds can be on the absolute value of a variable or its delta value. In addition, alarm thresholds may be autocalibrated or set manually.

Alarms are used to inform you of a network performance problem and they can trigger automated action responses through the Events group.

Hosts

The Hosts group specifies a table of traffic and error statistics for each host on a LAN segment or VLAN. Statistics include packets sent and received, octets sent and received, as well as broadcasts, multicasts, and error packets sent.

The group supplies a simple discovery mechanism listing all hosts that have transmitted. The next group, Hosts Top N, requires implementation of the Hosts group.

Hosts Top N

The Hosts Top N group extends the Hosts table by providing sorted host statistics, such as the top 20 nodes sending packets or an ordered list of all nodes according to the errors they sent over the last 24 hours.

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Matrix

The Matrix group shows the amount of traffic and number of errors between pairs of devices on a LAN segment or VLAN. For each pair, the Matrix group maintains counters of the number of packets, number of octets, and error packets between the nodes.

The conversation matrix helps you to examine network statistics in more detail to discover who is talking to whom or if a particular PC is producing more errors when communicating with its file server, for example. Combined with Hosts Top N, this allows you to view the busiest hosts and their primary conversation partners.

Filter

The Filter group provides a mechanism to instruct the RMON probe to capture packets that match a specific criterion or condition.

Capture

The Capture group allows you to create capture buffers on the probe that can be requested and uploaded to the management workstation for decoding and presentation.

Events

The Events group provides you with the ability to create entries in an event log and/or send SNMP traps to the management workstation. Events can originate from a crossed threshold on any RMON variable. In addition to the standard five traps required by SNMP (link up, link down, warm start, cold start, and authentication failure), RMON adds two more: rising threshold and falling threshold.

Effective use of the Events group saves you time; rather than having to watch real-time graphs for important occurrences, you can depend on the Event group for notification. Through the SNMP traps, events can trigger other actions providing a mechanism for an automated response to certain occurrences.

RMON 5-25

Benefits of RMON

Using the RMON features of your Switch has three main advantages:

It improves your efficiency

■

It allows you to manage your network in a more

■

proactive manner It reduces the load on the network and the man-

■

agement workstation

How RMON Improves Your Efficiency

Using RMON probes allows you to remain at one workstation and collect information from widely dispersed LAN segments or VLANs. This means that the time taken to reach a problem site, set up equipment, and begin collecting information is largely eliminated.

How RMON Allows Proactive Management

If they are configured correctly, RMON probes deliver information before problems occur. This means that you can take action before they impact on users. In addition, probes record the behavior of your network, so that you can analyze the causes of problems.

How RMON Reduces the Traffic Load

Traditional network management involves a management workstation polling network devices at regular intervals to gather statistics and identify problems or trends. As network sizes and traffic levels grow, this approach places a strain on the management workstation and also generates large amounts of traffic.

An RMON probe, however, autonomously looks at the network on behalf of the management workstation without affecting the characteristics and performance of the network. The probe reports by exception, which means that it only informs the management workstation when the network has entered an abnormal state.

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RMON and the Switch

RMON requires one probe per LAN segment, and stand-alone RMON probes have traditionally been expensive. Therefore, 3Com’s approach has been to build an inexpensive RMON probe into the SmartAgent of each Switch. This allows RMON to be widely deployed around the network without costing more than traditional network management.

A problem with stand-alone RMON probes is that they are passive; able to monitor and report, but nothing more. Placing probe functionality inside the network device allows integration of RMON with normal device management to allow proactive management.

For example, statistics can be related to individual ports and the Switch can take autonomous actions such as disabling a port (temporarily or permanently) if errors on that port exceed a pre-defined threshold. Also, since a probe needs to be able to see all traffic, a stand-alone probe has to be attached to a non-secure port. Implementing RMON in the Switch means all ports can have security features enabled.

RMON Features of the Switch

Tab le 5 -2 details the RMON support provided by

the Switch.

Table 5-2

RMON Group Support supplied by the Switch Statistics

History

Alarms

RMON support supplied by the Switch

A new or initialized Switch has one Statistics session per port/VLAN.

A new or initialized Switch has three History sessions on the 100BASE-TX port, backbone port and Default VLAN:

■

60-second intervals, 120 historical samples stored

■

30-second intervals, 120 historical samples stored

■

30-minute intervals, 96 historical samples stored

Although up to 700 alarms can be defined for the Switch, a new or initialized Switch has four alarms defined for each port:

■

Bandwidth used

■

Broadcast bandwidth used

■

Percentage of packets forwarded

■

Errors per 10,000 packets

You can modify these alarms using an RMON management application, but you cannot create or delete them.

For more information about the alarms setup on the Switch, refer to “About Alarm Actions” on

page 5-28

on page 5-29

and “About Default Alarm Settings”

3COM Link 1000 User Manual

Specifications and Main Features

Frequently Asked Questions

User Manual

Introduction

How to Use This Guide

Conventions

Related Documentation

About the Switch 1000

Summary of Features

Port Connections

Switch Operation and Features

Switch 1000 on Your Network

Server Connections

Network Configuration Examples

Network Segmentation I

Network Segmentation II

Desktop Switching

Unit Overview — Front

10BASE-T Ports

100BASE-TX Port

LEDs

Power Socket

Unit Serial Number

Redundant Power System Socket

Reset Button

Console Port

Plug-in Module Slot

Transceiver Module Slot

Ethernet Address

Unit Defaults

Managing the Switch 1000

Quick Start For SNMP Users

Entering an IP Address for the Switch

Following Safety Information

Positioning the Switch 1000

Configuration Rules for Fast Ethernet

Configuration Rules with Full Duplex

Installing the Switch 1000

Rack Mounting

Stacking the Switch and Other Units

Wall Mounting

Powering-up the Switch

Connecting a Redundant Power System (RPS)

Connecting Equipment to the Console Port

Connecting a VT100 Terminal

Connecting a VT100 Terminal Emulator

Connecting a Workstation Running SLIP

Methods of Managing the Switch 1000

Using the VT100 Management Interface

Using Telnet

Managing Over The Network

IP Addresses

Navigating the VT100 Screens

Screen Conventions

Keyboard Shortcuts

Correcting Text Entry

Setting Up the Switch for Management

Logging On

Switch Management Setup

Logging Off

Auto Logout

Setting Up Users

Creating a New User

Deleting a User

Editing User Details

Assigning Local Security

Choosing a Switch Management Level

Setting Up the Switch Unit

Setting Up the Switch Ports

Setting Up the Switch Database (SDB)

The Database View

Searching the Switch Database

Adding an Entry into the SDB

Deleting an Entry from the SDB

Specifying that an Entry is Permanent

Setting Up Resilient Links

Configuring Resilient Links

Creating a Resilient Link Pair

Deleting a Resilient Link