Enterasys VH-2402S Management Manual

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9033645-01

VERTICAL HORIZON

VH-2402S

FAST ETHERNET SWITCH

MANAGEMENT GUIDE

Notice

9033645-01 i

NOTICE

Enterasys Networks reserves the right to make changes in specifications and other information contained in this document without prior notice. The reader should in all cases consult Enterasys Networks to determine whether any such changes have been made.

The hardware, firmware, or software described in this manual is subject to change without notice.

IN NO EVENT SHALL ENTERASYS NETWORKS BE LIABLE FOR ANY INCIDENTAL, INDIRECT, SPECIAL, OR CONSEQUENTIAL DAMAGES WHATSOEVER (INCLUDING BUT NOT LIMITED TO LOST PROFITS) ARISING OUT OF OR RELATED TO THIS MANUAL OR THE INFORMATION CONTAINED IN IT, EVEN IF ENTERASYS NETWORKS HAS BEEN ADVISED OF, KNOWN, OR SHOULD HAVE KNOWN, THE POSSIBILITY OF SUCH DAMAGES.

 2000 by Enterasys Networks, Inc. P.O. Box 5005, Rochester, NH 03866-5005

Order Number: 9033645-01 December 2000

Enterasys, Enterasys Networks, and Vertical Horizon are trademarks or registered trademarks of Enterasys Networks, Inc.

Microsoft, Windows, Windows 95, Windows 98, and Windows NT are either trademarks or registered trademarks of Microsoft Corporation.

Netscape and Netscape Navigator are trademarks of Netscape Communications Corporation.

All other product names mentioned in this manual may be trademarks or registered trademarks of their respective companies.

Only qualified personnel should perform installation procedures.

Notice

ii 9033645-01

9033645-01 Table of Contents iii

TABLE OF CONTENTS

1. MANAGEMENT OVERVIEW. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

Configuration Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

Required Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

Console Port (Out-of-Band) Connections . . . . . . . . . . . . . . . . . . . . 1

Remote Management via the Console Port. . . . . . . . . . . . . . . . . . . 2

In-Band Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

2. VH-2402S USER INTERFACE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

User Access . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

Factory Defaults . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Main Menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

System Information Menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Displaying System Information . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

Displaying Switch Version and Module Information. . . . . . . . . . . . 13

Management Setup Menu. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

Changing the Network Configuration . . . . . . . . . . . . . . . . . . . . . . . 15

IP Configuration. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

IP Connectivity Test (Ping) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

HTTP Configuration. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

Configuring the Serial Port. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

Assigning SNMP Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

Console Login Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

Downloading System Software . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

Saving the System Configuration . . . . . . . . . . . . . . . . . . . . . . . . . 25

Configuring Management Access . . . . . . . . . . . . . . . . . . . . . . . . . 26

Configuring the Switch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

Configuring Port Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

Viewing the Current Port Configuration . . . . . . . . . . . . . . . . . . . . . 30

Using the Spanning Tree Algorithm . . . . . . . . . . . . . . . . . . . . . . . . 31

Viewing the Current Spanning Tree Configuration . . . . . . . . . . . . 34

Using a Mirror Port for Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . 38

Configuring Port Trunks. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39

IGMP Multicast Filtering. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41

Configuring Broadcast Storm Control . . . . . . . . . . . . . . . . . . . . . . 43

Configuring Bridge MIB Extensions . . . . . . . . . . . . . . . . . . . . . . . . 44

Configuring Traffic Classes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46

Configuring Virtual LANs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49

Multicast Router Port Information . . . . . . . . . . . . . . . . . . . . . . . . . 54

Static Multicast Router Port Configuration. . . . . . . . . . . . . . . . . . . 55

IGMP Member Port Configuration . . . . . . . . . . . . . . . . . . . . . . . . . 56

Port Security Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57

Monitoring the Switch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58

Displaying Port Statistics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59

Displaying RMON Statistics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60

iv Table of Contents VH-2402S

Displaying the Unicast Address Table . . . . . . . . . . . . . . . . . . . . . 62

Displaying the IP Multicast Registration Table . . . . . . . . . . . . . . . 63

Configuring Static Unicast Addresses. . . . . . . . . . . . . . . . . . . . . . 64

Resetting the System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65

Logging Off the System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65

3. CONFIGURING & MONITORING THE SWITCH . . . . . . . . . . . . . . . . . . . . . 67

Common Tasks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67

Setting Password Protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68

Assigning an IP Address . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69

Checking Network Configuration Status. . . . . . . . . . . . . . . . . . . . . . . . 69

Connecting via Telnet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69

Setting SNMP Management Access . . . . . . . . . . . . . . . . . . . . . . . . . . 70

Viewing Switch Statistics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70

Configuring Port Mirroring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71

Downloading a Software Upgrade . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71

Downloading Via the Serial Port . . . . . . . . . . . . . . . . . . . . . . . . . . 72

Downloading Via TFTP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72

Configuring Spanning Tree Parameters. . . . . . . . . . . . . . . . . . . . . . . . 74

Configuring VLANs. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75

Configuring Class of Service . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75

Configuring Port Operation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76

Configuring the Unicast Address Table . . . . . . . . . . . . . . . . . . . . . . . . 77

Setting a Default Gateway . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78

Configuring BootP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78

Configuring Port Trunks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79

4. SNMP MANAGEMENT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81

The SNMP Protocol . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81

MIB Objects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82

RFC 1213 (MIB-II). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83

RFC 1573 (Interfaces Evolution MIB) . . . . . . . . . . . . . . . . . . . . . . 83

RFC 1643 (Ethernet-Like MIB) . . . . . . . . . . . . . . . . . . . . . . . . . . . 83

RFC 1493 (Bridge MIB). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83

RFC 1757 (RMON MIB) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84

IEEE 802.1Q (Q-MIB) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84

Enterasys Proprietary MIB Extensions . . . . . . . . . . . . . . . . . . . . . 84

Compiling MIB Extensions: Enterasys Website . . . . . . . . . . . . . . . . . . 84

APPENDIX A. SPANNING TREE CONCEPTS . . . . . . . . . . . . . . . . . . . . . . . . 85

General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85

Spanning Tree Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85

Spanning Tree Protocol in a Network. . . . . . . . . . . . . . . . . . . . . . . . . . 86

Spanning Tree Protocol Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . 87

Spanning Tree Protocol Operation. . . . . . . . . . . . . . . . . . . . . . . . . . . . 88

Communicating Between Bridges . . . . . . . . . . . . . . . . . . . . . . . . . 88

Selecting a Root Bridge and Designated Bridges . . . . . . . . . . . . . 88

Selecting Designated Ports. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88

Handling Duplicate Paths . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88

9033645-01 Table of Contents v

Remapping Network Topology . . . . . . . . . . . . . . . . . . . . . . . . . . . 88

APPENDIX B. VIRTUAL LANS (VLANS) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91

VLANs and Frame Tagging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91

VH-2402S VLAN Configuration. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92

Assigning Ports to VLANs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92

Forwarding Tagged/Untagged Frames . . . . . . . . . . . . . . . . . . . . . . . . . 93

Forwarding Traffic with Unknown VLAN Tags . . . . . . . . . . . . . . . . . . . 93

Automatic VLAN Registration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94

APPENDIX C. CLASS OF SERVICE. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95

APPENDIX D. IP MULTICAST FILTERING . . . . . . . . . . . . . . . . . . . . . . . . . . . 97

IGMP Snooping and IP Multicast Filtering . . . . . . . . . . . . . . . . . . . . . . 97

INDEX

vi Table of Contents VH-2402S

9033645-01 Management Overview 1

1. MANAGEMENT OVERVIEW

Configuration Options

For advanced management capability, the VH-SMGMT Vertical Horizon Management Module provides a menu-driven system configuration program. This program can be accessed by a direct or modem connection to the serial port on the Management Module (out-of-band), or by a Telnet connection over the network (in-band).

The Management Module is based on SNMP (Simple Network Management Protocol). This SNMP agent permits a switch stack to be managed from any PC in the network using in-band management software.

The Management Module also includes an embedded HTTP Web agent. This Web agent can be accessed using a standard Web browser from any computer attached to the network. Refer to the Web Management Guide for more information.

The system configuration program and the SNMP agent support management functions such as:

• Enable/disable any port

• Set the communication mode for any port

• Configure SNMP parameters

• Select RMON options

• Display system information or statistics

• Configure the switch to join a Spanning Tree

• Download system firmware

• Restart the system

Required Connections

Console Port (Out-of-Band) Connections

Attach a VT100 compatible terminal or a PC running a terminal emulation program to the serial port on the Management Module. Use the nullmodem cable provided with this package, or use a null-modem connection that is compatible with the console port pin assignments shown in Appendix A of the VH-2402S User Guide.

2 Management Overview VH-2402S

When attaching to a PC, set terminal emulation type to VT100, specify the port used by your PC (i.e., COM 1~4), and then set communications to 8 data bits, 1 stop bit, no parity, and 19200 bps (for initial configuration). Also be sure to set flow control to “none.” (Refer to “Configuring the Serial Port” on page 19 for a complete description of configuration options.)

Remote Management via the Console Port

Configure the Switch Site

Connect the Management Module’s DB9 serial port to the modem’s serial port using standard cabling. For most modems which use a 25-pin port, you will have to provide an RS232 cable with a 9-pin connector on one end and a 25-pin connector on the other end. Set the modem at the switch’s site to force auto-answer mode. The following is a sample initialization string: “ATQ1S0=1&D0&K0&W” as defined below:

Q1 : Inhibit result codes to DTE S0=1 : Auto answer on first ring D0 : Don’t care DTR K0 : Disables DTE/DCE flow control W : Write command to modem memory

Configure the Remote Site

At the remote site, connect the PC’s COM port (COM 1~4) to the modem’s serial port. Set terminal emulation type to VT100, specify the port used by your PC (i.e., COM 1~4), and then set communications to 8 data bits, 1 stop bit, no parity, 19200 bps and no flow control.

In-Band Connections

Prior to accessing the Management Module via a network connection, you must first configure it with a valid IP address, subnet mask, and default gateway using an out-of-band connection or the BootP protocol.

Telnet Connection

Prior to accessing the Management Module via an in-band Telnet connection, you must first configure it with a valid IP address, subnet mask, and default gateway using an out-of-band connection or BootP protocol. After configuring the switch’s IP parameters, you can access the on-board configuration program from anywhere within the attached network.

Use the Network Configuration menu to specify the

maximum number of simultaneous Telnet sessions that

are supported by the system.

9033645-01 Management Overview 3

In-Band Network Connection

The on-board configuration program can be accessed using Telnet from any computer attached to the network. The switch and stack can also be managed by any computer using a Web browser (Internet Explorer 4.0 or above, or Netscape Navigator 4.0 or above), or from a network computer using network management software.

4 Management Overview VH-2402S

9033645-01 VH-2402S User Interface 5

2. VH-2402S USER INTERFACE

Overview

Access is gained to the console menus by connecting a terminal to the console port (with a direct cable connection or over modems), or using Telnet to access the Management Module over the network. These menus allow you to reconfigure the switch, as well as to monitor the status and performance of the switch or the attached stack. The menus have a layout similar to the sample Main Menu shown in Figure 2-1. The information is divided into the following parts:

• Menu Name (includes access privileges)

• Selectable Items

• Screen Prompt for menu selections and entry of field parameters,

and Message Area for display of parameters or error messages.

Figure 2-1. Sample Main Menu

Menu name

Selectable

Items

Screen prompt

and message

area

Vertical Horizon Local Management -- VH-2402S

Main Menu

System Information Menu...

Management Setup Menu...

Device Control Menu...

Network Monitor Menu...

System Restart Menu...

Exit

Use <TAB> or arrow keys to move. <Enter> to select.

6 VH-2402S User Interface VH-2402S

User Access

Once a direct connection to the serial port or a Telnet connection is established, the login screen for the on-board configuration program appears

. You may need to press Enter a few times to display the screen.

The default user names are “admin” and “guest,” with no passwords. The administrator has Read/Write access, which allows you to read and modify switch information. The guest has Read Only access to the management program, which allows you to view switch information, but not modify any operating parameters.

You should define a new administrator password, record it and put it in a safe place. From the Main Menu, select Management Setup Menu / Console Login Configuration, and enter a new password for the default administrator. Passwords can consist of up to 11 alphanumeric characters and are not case sensitive.

To use the console menus, do the following:

1. Use the cursor keys to highlight the desired option.

If the selected item is a submenu title, the submenu is displayed when you press the Enter key.

2. Follow the screen prompts to specify the parameter requested.

If the selected item is a parameter, the system displays a prompt for you to enter a new value. If the value entered is invalid, a message displays, requesting you to enter a valid value.

A user is allowed three attempts to enter the correct

password; on the third failed attempt the current

connection is terminated.

9033645-01 VH-2402S User Interface 7

Factory Defaults

Table 2-1 lists the default settings for switch configuration parameters. Each parameter can be changed via the console menus or Telnet.

Table 2-1. Factory Default Settings

Parameter Default Value

Multicast Filtering

GMRP Disabled

IGMP Multicast Filtering Disabled

Port Configuration

Flow Control Disabled

Speed and Duplex Auto

Admin Enabled

Broadcast Storm Control Enabled - 500 pps

Port Priority

Default Ingress User Priority 0

Spanning Tree Algorithm

Active Aging Time 300

Bridge Priority 32768

Forward Delay 15

Hello Time 2

Max Age 20

Path Cost 4 - 1000Mbps ports

19 - 100Mbps ports 100 - 10Mbps ports

Port Priority 128

Spanning Tree Protocol Enabled

System Configuration

Management VLAN All

BootP Enable Disabled

Password <none>

Screen Timeout 10 min

Send Authentication Fail Traps Enabled

SNMP Community Name public, private

Terminal Baud Rate Auto

User Names admin, guest

8 VH-2402S User Interface VH-2402S

Virtual LANs

Acceptable VLAN Frame Type All

Configurable PVID Tagging Yes

GVRP Disabled

Untagged VLAN Group Assignment 1

VLAN Ingress Filtering False

VLAN Learning SVL

Parameter Default Value

9033645-01 VH-2402S User Interface 9

Main Menu

The Main Menu is the first screen seen after successfully logging into the system. Figure 2-2 shows the Main Menu and the accompanying table describes the Main Menu

Figure 2-2. Main Menu

Vertical Horizon Local Management -- VH-2402S

Main Menu

System Information Menu...

Management Setup Menu...

Device Control Menu...

Network Monitor Menu...

System Restart Menu...

Exit

Use <TAB> or arrow keys to move. <Enter> to select.

Selection Description

System Information Menu

System Information Provides basic system description, including contact

information.

Switch Information Shows hardware/firmware version numbers, power status,

and expansion modules used in the stack.

Management Setup Menu

Network Configuration Includes IP setup, Ping facility, HTTP (Web Agent) setup,

Telnet configuration, and MAC address.

Serial Port Configuration

Sets communication parameters for the serial port, including management mode, baud rate, console time-out, and screen data refresh interval.

SNMP Configuration Activates traps; and configures communities and trap

managers.

Console Login Configuration

Sets user names and passwords for system access, as well as the invalid password threshold and lockout time.

TFTP Download Downloads new version of firmware to update your system

(in-band).

Configuration Save & Restore

Saves the switch configuration to a file on a TFTP server. This file can be later downloaded to restore the configuration.

Management Configuration

Specifies if management access to the switch is available from all VLANs or restricted to one VLAN.

10 VH-2402S User Interface VH-2402S

Device Control Menu

Port Configuration Enables any port, enables/disables flow control, and sets

communication mode to auto-negotiation, full duplex or half duplex.

Port Information Displays operational status, including link state, flow control

method, and duplex mode.

Spanning Tree Configuration

Enables Spanning Tree Algorithm; also sets parameters for hello time, maximum message age, switch priority, and forward delay; as well as port priority and path cost.

Spanning Tree Information

Displays full listing of parameters for the Spanning Tree Algorithm.

Mirror Port Configuration

Sets the source and target ports for mirroring.

Port Trunking Configuration

Specifies ports to group into aggregate trunks.

IGMP Configuration Configures IGMP multicast filtering.

BStorm Control Configuration

Allows you to enable broadcast storm control and set the packet-per-second threshold.

Extented Bridge Configuration

Displays/configures extended bridge capabilities provided by this switch, including support for traffic classes, GMRP multicast filtering, and VLAN extensions.

802.1P Configuration Configures default port priorities and queue assignments.

802.1Q VLAN Base Information

Displays basic VLAN information, such as VLAN version number and maximum VLANs supported.

802.1Q VLAN Current Table Information

Displays VLAN groups and port members.

802.1Q VLAN Static Table Configuration

Configures VLAN groups via static assignments, including setting port members, or restricting ports from being dynamically added to a port by the GVRP protocol.

Port Assignment VLAN Configuration

Displays/configures port-specific VLAN settings, including PVID, ingress filtering, and 802.1Q trunks.

Multicast Router Port Information

Displays the ports on the switch attached to a neighboring multicast router/switch for each VLAN ID.

Static Multicast Router Port Cfg

Assigns ports that are attached to a neighboring multicast router/switch.

IGMP Member Port Configuration

Assigns ports that are attached to hosts who want to receive a specific multicast service.

Port Security Configuration

Allows you to enable and configure port security for the switch.

Network Monitor Menu

Port Statistics Displays statistics on network traffic passing through the

selected port.

RMON Statistics Displays detailed statistical information for the selected port

such as packet type and frame size counters.

Unicast Address Table Provides full address listing, as well as search and clear

functions.

Selection Description

9033645-01 VH-2402S User Interface 11

System Information Menu

Use the System Information Menu to display a basic description of the switch, including contact information, and hardware/firmware versions.

Figure 2-3. System Information Menu

IP Multicast Registration Table

Displays all the multicast groups active on this switch, including multicast IP addresses and corresponding VLAN IDs.

Static Unicast Address Table Configuration

Used to manually configure host MAC addresses in the unicast table.

System Restart Restarts system with options to use POST, or to retain

factory defaults, IP settings, or user authentication settings.

Exit Exits the configuration program.

Vertical Horizon Local Management -- VH-2402S

System Information Menu

System Information ...

Switch Information ...

<OK>

Use <TAB> or arrow keys to move. <Enter> to select.

Selection Description

System Information Provides basic system description, including contact

information.

Switch Information Shows hardware/firmware version numbers, power status, and

expansion modules used in the stack.

Selection Description

12 VH-2402S User Interface VH-2402S

Displaying System Information

Use the System Information screen to display descriptive information about the switch, or for quick system identification as shown in the following figure and table.

Figure 2-4. System Information

Vertical Horizon Local Management -- VH-2402S

System Information

System Description : Vertical Horizon VH-2402S

System Object ID : 1.3.6.1.4.1.52.3.9.1.10.7

System Up Time : 48067 (0 day, 1 hr, 2min, 34 sec)

System Name : DEFAULT SYSTEM NAME

System Contact : DEFAULT SYSTEM CONTACT

System Location : DEFAULT SYSTEM LOCATION

Use <TAB> or arrow keys to move, other keys to make changes.

Parameter Description

System Description System hardware description.

System Object ID MIB II object identifier for switch’s network management

subsystem.

System Up Time Length of time the current management agent has been

running. (Note that the first value is 1/100 seconds.)

System Name

Name assigned to the switch system.

System Contact

Contact person for the system.

System Location

Specifies the area or location where the system resides.

Maximum string length is 99, but the screen only displays 45 characters. You

can use the arrow keys to browse the whole string.

9033645-01 VH-2402S User Interface 13

Displaying Switch Version and Module Information

Use the Switch Information screen to display hardware/firmware version numbers for the main board and agent module, as well as the power status and modules plugged into the system.

Figure 2-5. Switch Information

Vertical Horizon Local Management -- VH-2402S

Switch Information :

Unit 1

Main Board Hardware Version : V3.0 Firmware Version : V1.11 Serial Number : 89-34-33-22-11-00 Port Number : 25 Internal Power Status : Active Redundant Power Status : Inactive Expansion Slot 1 : 1000Base-SX Expansion Slot 2 : Stacking

Agent Module Hardware Version : V3.0 (801 CPU) POST ROM Version : V1.10 Firmware Version : 02.04.01.00 SNMP Agent : Master

Use <TAB> or arrow keys to move. <Enter> to select

Parameter Description

Main Board

Hardware Version Hardware version of the main board.

Firmware Version System firmware version in ROM.

Serial Number MAC address associated with the main board.

Port Number Number of ports in this unit.

Internal Power Status Power status for the switch.

Redundant Power Status

Redundant power status for the switch.

Expansion Slot 1 Shows module type if inserted

(100Base-FX, 1000Base-SX or 1000Base-LX).

Expansion Slot 2. Shows module type if inserted

(100Base-FX, 1000Base-SX, 1000Base-LX or Stacking).

Agent Module

Hardware Version Hardware version of the agent module.

POST ROM Version Power-On Self-Test version number.

Firmware Version Firmware version of the agent module.

SNMP Agent Shows if this module is Master or Backup Master.

14 VH-2402S User Interface VH-2402S

Management Setup Menu

After initially logging onto the system, adjust the communication parameters for your console to ensure a reliable connection (Serial Port Configuration). Specify the IP addresses for the agent module (Network Configuration / IP Configuration), and then set the Administrator and User passwords (Console Login Configuration). Remember to record them in a safe place. Also set the community string which controls access to the onboard SNMP agent via in-band management software (SNMP Configuration). The items provided by the Management Setup Menu are described in the following sections.

Figure 2-6. Management Setup Menu

Vertical Horizon Local Management -- VH-2402S

Management Setup Menu

Network Configuration ... Serial Port Configuration ... SNMP Configuration ... Console Login Configuration ... TFTP Download ... Configuration Save & Restore ... Management Configuration ...

<OK>

Use <TAB> or arrow keys to move. <Enter> to select.

Selection Description

Network Configuration

Includes IP setup, Ping facility, HTTP (Web Agent) setup, Telnet configuration, and MAC address.

Serial Port Configuration

Sets communication parameters for the serial port, including management mode, baud rate, console time-out, and screen data refresh interval.

SNMP Configuration Activates traps; and configures communities and trap managers.

Console Login Configuration

Sets user names and passwords for system access, as well as the invalid password threshold and lockout time.

TFTP Download Downloads new version of firmware to update your system (in-

band).

Configuration Save & Restore

Saves the switch configuration to a file on a TFTP server. This file can be later downloaded to restore the configuration.

Management Configuration

Specifies if management access to the switch is available from all VLANs or restricted to one VLAN.

9033645-01 VH-2402S User Interface 15

Changing the Network Configuration

Use the Network Configuration menu to set the bootup option, configure the switch’s Internet Protocol (IP) parameters, enable the on-board Web Agent, or to set the number of concurrent Telnet sessions allowed. The screen shown below is described in the following table.

Figure 2-7. Network Configuration

Vertical Horizon Local Management -- VH-2402S

Network Configuration

IP Configuration ...

IP Connectivity Test (Ping) ...

HTTP Configuration ...

MAX Number of allowed Telnet sessions (1 -4) : 4

MAC Address : 00-E0-29-52-28-00

Use <TAB> or arrow keys to move. <Enter> to select.

Parameter Description

IP Configuration Screen used to set the bootup option, or configure the switch’s IP

parameters.

IP Connectivity Test Screen used to test IP connectivity to a (Ping) specified device.

HTTP Configuration Screen used to enable the Web Agent.

MAX Number of Allowed Telnet Sessions

The maximum number of Telnet sessions allowed to simultaneously access the agent module.

MAC Address Physical address of the agent module.

16 VH-2402S User Interface VH-2402S

IP Configuration

Use the IP Configuration screen to set the bootup option, or configure the switch’s IP parameters. The screen shown below is described in the following table.

Figure 2-8. IP Configuration

Vertical Horizon Local Management -- VH-2402S

Network Configuration: IP Configuration

Interface Type : Ethernet

IP Address : 10.1.0.1 Subnet Mask : 255.255.0.0 Gateway IP : 10.1.0.254 IP State : USER-CONFIG

Use <TAB> or arrow keys to move, other keys to make changes.

Parameter Default Description

Interface Type Ethernet Indicates IP over Ethernet.

IP Address 10.1.0.1 IP address of the stack you are managing when

accessing the agent module over the network. The agent module supports SNMP over UDP/IP transport protocol. In this environment, all systems on the Internet, such as network interconnection devices and any PC accessing the agent module (or running management software) must have an IP address.

Valid IP addresses consist of four numbers, of 0 to 255, and separated by periods. Anything outside of this format will not be accepted by the configuration program.

Subnet Mask 255.255.0.0 Subnet mask of the agent you have selected. This

mask identifies the host address bits used for routing to specific subnets.

Default Gateway 0.0.0.0 Gateway used to pass trap messages from the

switch’s agent to the management station. Note that the gateway must be defined if the management station is located in a different IP segment.

IP State USER-

CONFIG

Specifies whether IP functionality is enabled via manual configuration, or set by Boot Protocol (BOOTP). Options include:

USER-CONFIG - IP functionality is enabled

based on the default or user specified IP Configuration. (This is the default setting.)

9033645-01 VH-2402S User Interface 17

IP Connectivity Test (Ping)

Use the IP Connectivity Test to see if another site on the Internet can be reached. The screen shown below is described in the following table.

Figure 2-9. IP Connectivity Test

Parameter Default Description

BOOTP Get IP - IP is enabled but will not function

until a BOOTP reply has been received. BOOTP requests will be periodically broadcast by the switch in an effort to learn its IP address. (BOOTP values can include the IP address, default gateway, and subnet mask.)

Vertical Horizon Local Management -- VH-2402S

Network Configuration: IP Connectivity Test (Ping)

IP Address : 200.123.211.109

Test Times : 1 Interval : 3

Success : 0 Failure : 0

[Start]

<OK>

Use <TAB> or arrow keys to move, other keys to make changes.

Parameter Description

IP Address IP address of the site you want to ping.

Test Times The number of ICMP echo requests to send to the specified site.

Range: 1~1000

Interval The interval (in seconds) between pinging the specified site.

Range: 1~10 seconds

Success/Failure The number of times the specified site has responded or not to

pinging.

18 VH-2402S User Interface VH-2402S

HTTP Configuration

Use the HTTP Configuration screen to enable/disable the on-board Web agent, and to specify the TCP port that will provide HTTP service. The screen shown below is described in the following table.

Figure 2-10. HTTP Configuration

Vertical Horizon Local Management -- VH-2402S

Network Configuration : HTTP Configuration

HTTP Server : ENABLED

HTTP Port Number : 80

Use <TAB> or arrow keys to move, <Space> to scroll options.

Parameter Description

HTTP Server Enables/disables access to the on-board Web agent.

HTTP Port Number Specifies the TCP port that will provide HTTP service.

Range : 0~65535 Default : Port 80 (Telnet Port 23 is prohibited.)

9033645-01 VH-2402S User Interface 19

Configuring the Serial Port

You can access the on-board configuration program by attaching a VT100 compatible device to the switch’s serial port. (For more information on connecting to this port, see “Required Connections” on page 1.) The communication parameters for this port can be accessed from the Serial Port Configuration screen shown below and described in the following table.

Figure 2-11. Serial Port Configuration

Vertical Horizon Local Management -- VH-2402S

Serial Port Configuration

Management Mode : CONSOLE MODE

Baudrate : 19200

Databits : 8

Stopbits : 1 Parity : NONE Time-Out (in minutes) : 10 Auto Refresh (in seconds) : 5

Use <TAB> or arrow keys to move, <Space> to scroll options.

Parameter Default Description

Management Mode Console Mode Indicates that the console port settings are for

direct console connection.

Baud Rate Auto The rate at which data is sent between devices.

Options : 2400, 4800, 9600, 19200 bps, and Auto detection

Databits 8 bits Sets the databits of the RS-232 port.

Options : 7, 8

Stopbits 1 bit Sets the stop bits of the RS-232 port.

Options : 1, 2

Parity none Sets the parity of the RS-232 port.

Options : none/odd/even

Time-Out 10 minutes If no input is received from the attached device

after this interval, the current session is automatically closed.

Range : 0 - 100 minutes; 0: disabled

Auto Refresh 5 seconds Sets the interval before a console session will

auto refresh the console information, such as Spanning Tree Information, Port Configuration, Port Statistics, and RMON Statistics.

Range : 5-255 seconds; 0: disabled

20 VH-2402S User Interface VH-2402S

Assigning SNMP Parameters

Use the SNMP Configuration screen to display and modify parameters for the Simple Network Management Protocol (SNMP). The switch includes an on-board SNMP agent which monitors the status of its hardware, as well as the traffic passing through its ports. A computer attached to the network, called a Network Management Station (NMS), can be used to access this information. Access rights to the on-board agent are controlled by community strings. To communicate with the switch, the NMS must first submit a valid community string for authentication. The options for configuring community strings and related trap functions are described in the following sections.

Figure 2-12. SNMP Configuration

Vertical Horizon Local Management -- VH-2402S

SNMP Configuration

Send Authentication Fail Traps : ENABLED

SNMP Communities ...

IP Trap Managers ...

Use <TAB> or arrow keys to move, <Space> to scroll options.

Parameter Description

Send Authentication Fail Traps

Issue a trap message to specified IP trap managers whenever authentication of an SNMP request fails. (The default is enabled.)

SNMP Communities Assigns SNMP access based on specified strings.

IP Trap Managers Specifies management stations that will receive authentication

failure messages or other trap messages from the switch.

9033645-01 VH-2402S User Interface 21

Configuring Community Names

The following figure and table describe how to configure the community strings authorized for management access. Up to 5 community names may be entered.

Figure 2-13. SNMP Communities

Vertical Horizon Local Management -- VH-2402S

SNMP Configuration : SNMP Communities

Community Name Access Status

1. public READ ONLY ENABLED

2. private READ/WRITE ENABLED

Use <TAB> or arrow keys to move, other keys to make changes.

Parameter Description

Community Name A community entry authorized for management access.

Maximum string length : 20 characters

Access Management access is restricted to Read Only or Read/Write.

Status Sets administrative status of entry to enabled or disabled.

Note: The default community strings are “public” with Read Only access, and “private” with Read/Write access.

22 VH-2402S User Interface VH-2402S

Configuring IP Trap Managers

The following figure and table describe how to specify management stations that will receive authentication failure messages or other trap messages from the switch. Up to 5 trap managers may be entered.

Figure 2-14. IP Trap Managers

Vertical Horizon Local Management -- VH-2402S

SNMP Configuration : IP Trap Managers

IP Address Community Name Status

1. 10.1.0.23 public DISABLED

Use <TAB> or arrow keys to move, other keys to make changes.

Parameter Description

IP Address IP address of the trap manager.

Community Name A community specified for trap management access.

Status Sets administrative status of selected entry to enabled or

disabled.

9033645-01 VH-2402S User Interface 23

Console Login Configuration

Use the Management Setup: Console Login Configuration to restrict management access based on specified user names and passwords, or to set the invalid password threshold and timeout. There are only two user types defined, ADMIN (Administrator) and GUEST, but you can set up to five different user names and passwords. Only Administrators have write access for parameters governing the switch. You should therefore assign a user name and password to the default Administrator as soon as possible, and store it in a safe place. (If for some reason your password is lost, or you cannot gain access to the System Configuration Program, contact Enterasys Technical Support for assistance.) The parameters shown on this screen are indicated in the following figure and table.

Figure 2-15. Console Login Configuration

Vertical Horizon Local Management -- VH-2402S

Console Login Configuration

Password Threshold : 3

Lock-out Time (in minutes) : 0

User Type User Name Password

------------------------------------------------

1. ADMIN : admin

2. GUEST : guest

Use <TAB> or arrow keys to move, other keys to make changes.

Parameter Default Description

Password Threshold 3 Sets the password intrusion threshold which limits

the number of failed logon attempts.

Range : 0~65535

Lock-out Time 0 The time (in seconds) the management console

will be disabled, due to an excessive number of failed logon attempts.

Range : 0~65535

Admin* name: admin

password: null

Administrator has access privilege of Read/Write for all screens.

Guest* name: guest

password: null

Guest has access privilege of Read Only for all screens.

* Passwords can consist of up to 11 alphanumeric characters and are not case sensitive.

24 VH-2402S User Interface VH-2402S

Downloading System Software

Using TFTP Protocol to Download Over the Network

Use the TFTP Download menu to load software updates into the switch. The download file should be an VH-2402S file from Enterasys; otherwise the agent will not accept it. The success of the download operation depends on the accessibility of the TFTP server and the quality of the network connection. After downloading the new software, the agent will automatically restart itself. Parameters shown on this screen are indicated in the following figure and table.

Figure 2-16. TFTP Download

Vertical Horizon Local Management -- VH-2402S

TFTP Download

Download Server IP : 0.0.0.0

Agent Software Upgrade : ENABLED

Download Filename : agent-v2.41 Download Mode : PERMANENT

[Process TFTP Download] Download Status : Complete

Use <TAB> or arrow keys to move, other keys to make changes.

Parameter Description

Download Server IP IP address of a TFTP server.

Agent Software Upgrade Indicates that the switch is enabled for software upgrades.

Download Filename The binary file to download to the agent module.

Download Mode Indicates that the download is to permanent flash ROM.

[Process TFTP Download]

Issues a request to the TFTP server to download the specified file.

Download Status Indicates if a download is “Complete” or “In Progress.”

9033645-01 VH-2402S User Interface 25

Saving the System Configuration

Use the Configuration Save & Restore menu to save the switch configuration settings to a file on a TFTP server. The file can be later downloaded to the switch to restore the switch’s settings. The success of the operation depends on the accessibility of the TFTP server and the quality of the network connection. Parameters shown on this screen are indicated in the following figure and table.

Figure 2-17. Configuration Save & Restore

Vertical Horizon Local Management -- VH-2402S

Configuration Upload

Upload Server IP : Upload Filename :

[Process TFTP Upload] Upload status : Complete

Configuration Download

Download Server IP : Download Filename :

[Process TFTP Download] Download status : Complete

Use <TAB> or arrow keys to move, other keys to make changes.

Parameter Description

Configuration Upload

Upload Server IP IP address of a TFTP server.

Upload Filename The name of the file to contain the switch configuration settings.

[Process TFTP Upload]

Issues a request to upload the configuration settings to the specified file on the TFTP server.

Upload Status Indicates if an upload is “Complete” or “In Progress.”

Configuration Download

Download Server IP IP address of a TFTP server.

Download Filename The name of the file that contains the switch configuration

settings you wish to restore.

[Process TFTP Download]

Issues a request to the TFTP server to download the specified file.

Download Status Indicates if a download is “Complete” or “In Progress.”

26 VH-2402S User Interface VH-2402S

Configuring Management Access

Use the Management Configuration menu to define which VLAN has management access to the switch. Parameters shown on this screen are indicated in the following figure and table.

Figure 2-18. Management Configuration

Vertical Horizon Local Management -- VH-2402S

Management Configuration

Management VLAN : ALL

VLAN : 1

Use <TAB> or arrow keys to move, <Space> to scroll options.

Parameter Default Description

Management VLAN All Select ALL to give all VLANs access to switch

management, or ONE to restrict access to a specified VLAN. If you select just one VLAN, you must specify its VLAN ID on the following line.

VLAN 1 Specifies the VLAN ID that has access to switch

management.

9033645-01 VH-2402S User Interface 27

Configuring the Switch

The Device Control menu is used to control a broad range of functions, including port configuration, Spanning Tree support for redundant switches, port mirroring, multicast filtering, and Virtual LANs. Each of the setup screens provided by these configuration menus is described in the following sections.

Figure 2-19. Device Control Menu

Vertical Horizon Local Management -- VH-2402S

Device Control Menu

Port Configuration ... Extended Bridge Configuration ... Port Information ... 802.1P Configuration ... Spanning Tree Configuration ... 802.1Q VLAN Base Information ... Spanning Tree Information ... 802.1Q VLAN Current Table Information ... Mirror Port Configuration ... 802.1Q VLAN Static Table Configuration ... Port Trunking Configuration ... Port Assigment VLAN Configuration ... IGMP Configuration ... Multicast Router Port Information ... BStorm Control Configuration ... Static Multicast Router Port Cfg ... Port GARP Configuration ... IGMP Member Port Configuration ... Port GMRP Configuration ... Port Security Configuration ...

<OK>

Use <TAB> or arrow keys to move. <Enter> to select.

Selection Description

Port Configuration Sets communication parameters for ports.

Port Information Displays current port settings and port status.

Spanning Tree Configuration

Configures the switch, its ports and modules to participate in a local Spanning Tree.

Spanning Tree Information

Displays the current Spanning Tree configuration for the switch, its ports and modules.

Mirror Port Configuration

Sets the source and target ports for mirroring.

Port Trunking Configuration

Specifies ports to group into aggregate trunks.

IGMP Configuration Configures IGMP multicast filtering.

BStorm Control Configuration

Allows you to enable broadcast storm control and set the packetper-second threshold.

Port GARP Configuration*

Configures generic attribute settings used in the spanning tree protocol, VLAN registration, multicast filtering.

Port GMRP Configuration*

Configures GMRP multicast filtering.

Extended Bridge Configuration

Displays/configures extended bridge capabilities provided by this switch, including support for traffic classes, and VLAN extensions.

802.1P Configuration Configures default port priorities and queue assignments.

28 VH-2402S User Interface VH-2402S

802.1Q VLAN Base Information

Displays basic VLAN information, such as VLAN version number and maximum VLANs supported.

802.1Q VLAN Current Table Information

Displays VLAN groups and port members.

802.1Q VLAN Static Table Configuration

Configures VLAN groups via static assignments, including setting port members, or restricting ports from being dynamically added to a port by the GVRP protocol.

Port Assignment VLAN Configuration

Displays/configures port-specific VLAN settings, including PVID, ingress filtering, and 802.1Q trunks.

Multicast Router Port Information

Displays the ports on the switch attached to a neighboring multicast router/switch for each VLAN ID.

Static Multicast Router Port Cfg

Assigns ports that are attached to a neighboring multicast router/ switch.

IGMP Member Port Configuration

Assigns ports that are attached to hosts who want to receive a specific multicast service.

Port Security Configuration

Allows you to enable and configure port security for the switch.

* Not implemented in the current firmware release.

Selection Description

9033645-01 VH-2402S User Interface 29

Configuring Port Parameters

Use the Port Configuration menus to set or display communication parameters for any port or module on the switch.

Figure 2-20. Port Configuration

Vertical Horizon Local Management -- VH-2402S

Port Configuration :

Unit 1 Port 1-12

Port Type Admin Flow Speed and Control Duplex

-------------------------------------------------------------------------

1. 10/100TX ENABLED ENABLED 10-HALF

2. 10/100TX ENABLED ENABLED 100-FULL

3. 10/100TX ENABLED ENABLED AUTO

4. 10/100TX ENABLED ENABLED AUTO

5. 10/100TX ENABLED ENABLED 10-FULL

6. 10/100TX ENABLED ENABLED 100-HALF

7. 10/100TX ENABLED ENABLED AUTO

8. 10/100TX ENABLED ENABLED AUTO

9. 10/100TX ENABLED ENABLED AUTO

10. 10/100TX ENABLED ENABLED AUTO

11. 10/100TX ENABLED ENABLED AUTO

12. 10/100TX ENABLED ENABLED AUTO

Use <TAB> or arrows keys to move. <Space> to scroll options.

Parameter Default Description

Type Shows port type as:

10/100TX : 10Base-T / 100Base-TX 100FX : 100Base-FX 1000SX : 1000Base-SX 1000LX : 1000Base-LX

Admin ENABLED Allows you to disable a port due to abnormal

behavior (e.g., excessive collisions), and then reenable it after the problem has been resolved. You may also disable a port for security reasons.

Flow Control DISABLED Used to enable or disable flow control. Flow

control can eliminate frame loss by “blocking” traffic from end stations or segments connected directly to the switch when its buffers fill. Back pressure is used for half duplex and IEEE 802.3x for full duplex. Note that flow control should not be used if a port is connected to a hub.

Speed and Duplex AUTO Used to set the current port speed, duplex mode,

and auto-negotiation. (Auto-negotiation is not available for 100Base-FX ports.)

30 VH-2402S User Interface VH-2402S

Viewing the Current Port Configuration

The Port Information screen displays the port type, status, link state, and flow control in use, as well as the communication speed and duplex mode. To change any of the port settings, use the Port Configuration menu. The parameters shown in the following figure and table are for the RJ-45 ports.

Figure 2-21. Port Information

Vertical Horizon Local Management -- VH-2402S

Port Information :

Unit 1 Port 1-12

Port Type Operational Link FlowControl Speed and

InUse Duplex InUse

-------------------------------------------------------------------------------------------------------

1. 10/100TX YES DOWN ----------------- ----------------

2. 10/100TX YES DOWN ----------------- ----------------

3. 10/100TX YES UP 802.3x 100-FULL

4. 10/100TX YES DOWN ----------------- ----------------

5. 10/100TX YES DOWN ----------------- ----------------

6. 10/100TX YES UP NONE 100-HALF

7. 10/100TX YES UP 802.3x 100-FULL

8. 10/100TX YES UP BACK_PRESSURE 10-FULL

9. 10/100TX YES UP BACK_PRESSURE 10-FULL

10. 10/100TX YES UP BACK_PRESSURE 10-FULL

11. 10/100TX YES UP BACK_PRESSURE 10-FULL

12. 10/100TX YES UP BACK_PRESSURE 10-FULL

Use <TAB> or arrows keys to move. <Enter> to select.

Parameter Description

Type Shows port type as:

10/100TX : 10Base-T / 100Base-TX 100FX : 100Base-FX 1000SX : 1000Base-SX 1000LX : 1000Base-LX

Operational Shows if the port is functioning or not.

Link Indicates if the port has a valid connection to an external device.

FlowControl InUse Shows the flow control type in use. Flow control can eliminate

frame loss by “blocking” traffic from end stations connected directly to the switch. Back pressure is used for half duplex and IEEE 802.3x for full duplex. Note that flow control should not be used if a port is connected to a hub.

Speed and DuplexInUse

Displays the current port speed and duplex mode used.

9033645-01 VH-2402S User Interface 31

Using the Spanning Tree Algorithm

The Spanning Tree Algorithm can be used to detect and disable network loops, and to provide backup links between switches, bridges or routers. This allows the switch to interact with other bridging devices (that is, an STA-compliant switch, bridge or router) in your network to ensure that only one route exists between any two stations on the network. For a more detailed description of how to use this algorithm, refer to Appendix A, “Spanning Tree Concepts” on page 85.

Figure 2-22. Spanning Tree Configuration

Configuring Bridge STA

The following figure and table describe Bridge STA configuration.

Figure 2-23. Bridge STA Configuration

Vertical Horizon Local Management -- VH-2402S

Spanning Tree Configuration : Selection Menu

STA Bridge Configuration ...

STA Port Configuration ...

<OK>

Use <TAB> or arrow keys to move. <Enter> to select.

Vertical Horizon Local Management -- VH-2402S

Spanning Tree Configuration : Bridge STA Configuration

Spanning Tree Protocol : ENABLED

Priority : 32768

Hello Time (in seconds) : 2

Max Age (in seconds) : 20

Forward Delay (in seconds) : 15

Use <TAB> or arrow keys to move, <Space> to scroll options,

32 VH-2402S User Interface VH-2402S

Parameter Default Description

Spanning Tree Protocol

Enabled Enable this parameter to participate in an STA

compliant network.

Priority 32,768 Device priority is used in selecting the root device,

root port, and designated port. The device with the highest priority becomes the STA root device. However, if all devices have the same priority, the device with the lowest MAC address will then become the root device.

Enter a value from 0 - 65535. Remember that the lower the numeric value, the higher the priority.

Hello Time 2 Time interval (in seconds) at which the root device

transmits a configuration message.

The minimum value is1. The maximum value is the lower of 10 or [(Max. Message Age / 2) -1].

Max (Message) Age 20 The maximum time (in seconds) a device can wait

without receiving a configuration message before attempting to reconfigure. All device ports (except for designated ports) should receive configuration messages at regular intervals. Any port that ages out STA information (provided in the last configuration message) becomes the designated port for the attached LAN. If it is a root port, a new root port is selected from among the device ports attached to the network.

The minimum value is the higher of 6 or [2 x (Hello Time + 1)]. The maximum value is the lower of 40 or [2 x (Forward Delay - 1)].

Forward Delay 15 The maximum time (in seconds) the root device

will wait before changing states (i.e., listening to learning to forwarding). This delay is required because every device must receive information about topology changes before it starts to forward frames. In addition, each port needs time to listen for conflicting information that would make it return to a blocking state; otherwise, temporary data loops might result.

The maximum value is 30. The minimum value is the higher of 4 or [(Max. Message Age / 2) + 1].

9033645-01 VH-2402S User Interface 33

Configuring STA for Ports or Modules

The following figure and table describe STA configuration for ports or modules. (Note that the Spanning Tree Configuration screen for the expansion slots also indicates module type.)

Figure 2-24. Spanning Tree Port Configuration

Vertical Horizon Local Management -- VH-2402S

Fast forwarding mode of all ports : [Enable] [Disable]

Spanning Tree Port Configuration :

Unit 1 Port 1-12

Port Type Priority Cost FastForwarding

--------------------------------------------------- 1 10/100TX 128 19 ENABLED 2 10/100TX 128 19 ENABLED 3 10/100TX 128 19 ENABLED 4 10/100TX 128 19 ENABLED 5 10/100TX 128 19 ENABLED 6 10/100TX 128 19 ENABLED 7 10/100TX 128 19 ENABLED 8 10/100TX 128 19 ENABLED 9 10/100TX 128 19 ENABLED 10 10/100TX 128 19 ENABLED 11 10/100TX 128 19 ENABLED 12 10/100TX 128 19 ENABLED

Use <TAB> or arrow keys to move, other keys to make changes.

Parameter Default Description

Fast forwarding mode of all ports

ENABLED Allows you to enable or disable fast forwarding for

all ports on the switch.

Type Shows 10/100TX, 100FX, 1000LX or 1000SX port.

Priority 128 Defines the priority for the use of a port in the STA

algorithm. If the path cost for all ports on a switch are the same, the port with the highest priority (i.e., lowest value) will be configured as an active link in the spanning tree. Where more than one port is assigned the highest priority, the port with lowest numeric identifier will be enabled.

The range is 0 - 255.

(Path) Cost 100/19/4 This parameter is used by the STA algorithm to

determine the best path between devices. Therefore, lower values should be assigned to ports attached to faster media, and higher values assigned to ports with slower media. (Path cost takes precedence over port priority.)

The default and recommended range is:

Ethernet: 100 (50~600) Fast Ethernet: 19 (10~60) Gigabit Ethernet: 4 (3~10)

The full range is 1 - 65535.

34 VH-2402S User Interface VH-2402S

Viewing the Current Spanning Tree Configuration

The Spanning Tree Information screen displays a summary of the STA information for the overall bridge or for a specific port or module. To make any changes to the parameters for the Spanning Tree, use the Spanning Tree Configuration menu.

Figure 2-25. Spanning Tree Information

FastForwarding ENABLED This parameter is used to enable/disabled the Fast

Spanning Tree mode for the port. In this mode,

ports skip the Blocked, Listening and Learning

states and proceed straight to Forwarding.

FastForwarding enables end-node workstations

and servers to overcome time-out problems when

the Spanning Tree Algorithm is implemented in a

network. Therefore, FastForwarding should only be

enabled for ports that are connected to an end-

node device.

Vertical Horizon Local Management -- VH-2402S

Spanning Tree Information : Selection Menu

STA Bridge Information ...

STA Port Information ...

<OK>

Use <TAB> or arrow keys to move. <Enter> to select.

Parameter Default Description

9033645-01 VH-2402S User Interface 35

Displaying the Current Bridge STA

The parameters shown in the following figure and table describe the current Bridge STA Information.

Figure 2-26. Bridge STA Information

Vertical Horizon Local Management -- VH-2402S

Spanning Tree Information : Bridge STA Information

Priority : 32768 Hello Time (in seconds) : 2 Max Age (in seconds) : 20 Forward Delay (in seconds) : 15 Hold Time (in seconds) : 1 Designated Root : 0.0000E800E800 Root Cost : 19 Root Port : 1 Configuration Changes : 2 Topology Up Time : 48069 (0 day, 1 hr, 2min, 34 sec)

<OK>

Use <Tab> or arrow keys to move, <Enter> to select.

Parameter Description

Priority Device priority is used in selecting the root device, root port, and

designated port. The device with the highest priority becomes the STA root device. However, if all devices have the same priority, the device with the lowest MAC address will then become the root device.

Hello Time The time interval (in seconds) at which the root device transmits a

configuration message.

Max Age The maximum time (in seconds) a device can wait without receiving a

configuration message before attempting to reconfigure.

Forward Delay The maximum time (in seconds) the root device will wait before

changing states (i.e., listening to learning to forwarding).

Hold Time The minimum interval between the transmission of consecutive

Configuration BPDUs.

Designated Root The priority and MAC address of the device in the spanning tree that

this switch has accepted as the root device.

Root Cost The path cost from the root port on this switch to the root device.

Root Port The number of the port on this switch that is closest to the root. This

switch communicates with the root device through this port. If there is no root port, then this switch has been accepted as the root device of the spanning tree network.

Configuration Changes

The number of times the spanning tree has been reconfigured.

Topology Up Time The time since the spanning tree was last reconfigured.

36 VH-2402S User Interface VH-2402S

Displaying the Current STA for Ports or Modules

The parameters shown in the following figure and table are for port or module STA Information (Port 1-12, Port 13-24, Port 25-32).

Figure 2-27. Spanning Tree Port Information

Vertical Horizon Local Management -- VH-2402S

Spanning Tree Port Information :

Unit 1 Port 1-12

Port Type Status Designated Designated Designated

Cost Bridge Port

-------------------------------------------------------------------------------------------------------

1. 10/100TX FORWARDING 0 0.0000E800E800 128.3

2. 10/100TX FORWARDING 19 32768.00E029522800 128.1

3. 10/100TX FORWARDING 19 32768.00E029522800 128.1

4. 10/100TX FORWARDING 19 32768.00E029522800 128.5

5. 10/100TX LISTENING 19 32768.00E029522800 128.6

6. 10/100TX LEARNING 19 32768.00E029522800 128.3

7. 10/100TX FORWARDING 19 32768.00E029522800 128.3

8. 10/100TX FORWARDING 19 32768.00E029522800 128.3

9. 10/100TX FORWARDING 19 32768.00E029522800 128.4

10. 10/100TX FORWARDING 19 32768.00E029522800 128.5

11. 10/100TX FORWARDING 19 32768.00E029522800 128.5

12. 10/100TX FORWARDING 19 32768.00E029522800 128.5

Use <TAB> or arrows keys to move. <Enter> to select.

Parameter Description

Type Shows port type as:

10/100TX : 10Base-T / 100Base-TX 100FX : 100Base-FX 1000SX : 1000Base-SX 1000LX : 100Base-LX

Status Displays the current state of this port within the spanning tree:

No Link There is no valid link on the port.

Disabled Port has been disabled by the user or has failed

diagnostics.

Blocking Port receives STA configuration messages, but does

not forward packets.

Listening Port will leave blocking state due to topology change,

starts transmitting configuration messages, but does not yet forward packets.

Learning Has transmitted configuration messages for an

interval set by the Forward Delay parameter without receiving contradictory information. Port address table is cleared, and the port begins learning addresses.

Forwarding The port forwards packets, and continues learning

addresses.

9033645-01 VH-2402S User Interface 37

The rules defining port status are:

• A port on a network segment with no other STA-compliant bridging device is always forwarding.

• If two ports of a switch are connected to the same segment and there is no other STA device attached to this segment, the port with the smaller ID forwards packets and the other is blocked.

• All ports are blocked when the switch is booted, then some of them change state to listening, to learning, and then to forwarding.

Designated Cost The cost for a packet to travel from this port to the root in the

current spanning tree configuration. The slower the media, the higher the cost.

Designated Bridge (ID)

The priority and MAC address of the device through which this port must communicate to reach the root of the spanning tree.

Designated Port (ID) The priority and number of the port on the designated bridging

device through which this switch must communicate with the root of the spanning tree.

Parameter Description

38 VH-2402S User Interface VH-2402S

Using a Mirror Port for Analysis

You can mirror traffic from any source port to a target port for real-time analysis. You can then attach a logic analyzer or RMON probe to the target port and study the traffic crossing the source port in a completely unobtrusive manner. When mirroring port traffic, note that the target port must be configured in the same VLAN and be operating at the same speed as the source port (see Configuring Virtual LANs on page 49). If the target port is operating at a lower speed, the source port will be forced to drop its operating speed to match that of the target port.

You can use the Mirror Port Configuration screen to designate a single port pair for mirroring as shown below:

Figure 2-28. Mirror Port Configuration

Vertical Horizon Local Management -- VH-2402S

Mirror Port Configuration

Mirror Source Port : Unit 1

Port 1

Mirror Target Port : Unit 1

Port 2

Status : DISABLED

Use <TAB> or arrow keys to move, other keys to make changes.

Parameter Description

Mirror Source Port The port whose traffic will be monitored.

Mirror Target Port The port that will duplicate or “mirror” all the traffic happening on

the monitored port.

Status Enables or disables the mirror function.

9033645-01 VH-2402S User Interface 39

Configuring Port Trunks

Port trunks can be used to increase the bandwidth of a network connection or to ensure fault recovery. You can configure up five trunk connections (combining 2~4 ports into a fat pipe) between any two standalone VH-2402S switches, or up to 12 for an entire stack. However, before making any physical connections between devices, use the Trunk Configuration menu to specify the trunk on the devices at both ends. When using a port trunk, note that:

• The ports used in a trunk must all be of the same media type (RJ-45,

100Mbps fiber, or 1000Mbps fiber). The ports that can be assigned to the same trunk also have certain other restrictions (see the next page).

• Ports can only be assigned to one trunk.

• The ports at both ends of a connection must be configured as trunk

ports.

• The ports at both ends of a trunk must be configured in an identical

manner, including speed, duplex mode, and VLAN assignments.

• None of the ports in a trunk can be configured as a mirror source port

or mirror target port.

• All the ports in a trunk have to be treated as a whole when moved

from/to, added or deleted from a VLAN.

• The Spanning Tree Algorithm will treat all the ports in a trunk as a

whole.

• Enable the trunk prior to connecting any cable between the switches

to avoid creating a loop.

• Disconnect all trunk port cables or disable the trunk ports before

removing a port trunk to avoid creating a loop.

40 VH-2402S User Interface VH-2402S

You can use the Port Trunking Configuration screen set up port trunks as shown below:

Figure 2-29. Port Trunking Configuration

The RJ-45 ports used for each trunk must all be on the same internal switch chip. The port groups permitted include:

Group 1 Group 2 Group 3

1,2,3,4, 5,6,7,8, 9,10,11,12, 13,14,15,16 17,18,19,20 21,22,23,24

Only two 100Mbps fiber ports can be configured as a trunk and these must be on the same module. However, 1000Mbps fiber ports may be on any module in the stack.

Vertical Horizon Local Management -- VH-2402S

Port Trunking Configuration

Trunk ID Status Member List 1 2 3 4

------------- ------------- ---------------- ---------------- ---------------- ----------------

-- ------------ Unit : - Unit : - Unit : - Unit : Port : -- Port : -- Port : -- Port : --

Trunk ID : 1 Trunk ID : 1 Member Unit : 1 Member Port : 1 [Show] [More] [Enable] [Disable] [Add] [Delete]

<OK>

Use <TAB> or arrow keys to move, other keys to make changes.

Parameter Description

Trunk ID Configure up to three trunks per switch.

Unit Specifies a switch unit in the stack (1~7).

Port Select from 2~4 ports per trunk.

[Show] Displays trunk settings, where the first trunk listed is specified by

“Sorted by Trunk ID.”

[More] Scrolls through the list of configured trunks.

[Enable] [Disable] Enables/disables the selected trunk.

9033645-01 VH-2402S User Interface 41

IGMP Multicast Filtering

Multicasting is used to support real-time applications such as video conferencing or streaming audio. A multicast server does not have to establish a separate connection with each client. It merely broadcasts its service to the network, and any hosts which want to receive the multicast register with their local multicast switch/router. Although this approach reduces the network overhead required by a multicast server, the broadcast traffic must be carefully pruned at every multicast switch/router it passes through to ensure that traffic is only passed on the hosts which subscribed to this service.

This switch uses IGMP (Internet Group Management Protocol) to query for any attached hosts who want to receive a specific multicast service. The switch looks up the IP Multicast Group used for this service and adds any port which received a similar request to that group. It then propagates the service request on to any neighboring multicast switch/router to ensure that it will continue to receive the multicast service. (For more information, see “IGMP Snooping and IP Multicast Filtering” on page 97.)

42 VH-2402S User Interface VH-2402S

Configuring IGMP

This protocol allows a host to inform its local switch/router that it wants to receive transmissions addressed to a specific multicast group. You can use the IGMP Configuration screen to configure multicast filtering shown below:

Figure 2-30. IGMP Configuration

Vertical Horizon Local Management -- VH-2402S

IGMP Configuration

IGMP Status : DISABLED

Act as IGMP Querier : DISABLED

IGMP Query Count : 2

IGMP Report Delay (Seconds) : 10

Use <TAB> or arrow keys to move, <Space> to scroll options.

Parameter Description

IGMP Status If enabled, the switch will monitor network traffic to determine

which hosts want to receive multicast traffic.

Act as IGMP Querier If enabled, the switch can serve as the “querier,” which is

responsible for asking hosts if they want to receive multicast traffic.

IGMP Query Count The maximum number of queries issued for which there has been

no response before the switch takes action to solicit reports. (Range: 2 - 10.)

IGMP Report Delay The time (in seconds) between receiving an IGMP Report for an

IP multicast address on a port before the switch sends an IGMP Query out of that port and removes the entry from its list. (Range: 5 - 30.)

Note: The default values are indicated in the sample screen.

9033645-01 VH-2402S User Interface 43

Configuring Broadcast Storm Control

Use the Broadcast Storm Control Configuration screen to enable broadcast storm control for any port on the switch, as shown below:

Figure 2-31. Broadcast Storm Control Configuration

Vertical Horizon Local Management -- VH-2402S

Broadcast Storm Control Configuration

: Unit 1 Port 1-12

Broadcast control on all ports : [Enable] [Disable] Port Threshold Broadcast Control

------------------------------------------------------ 1 500 ENABLED 2 500 ENABLED 3 500 ENABLED 4 500 ENABLED 5 500 ENABLED 6 500 ENABLED 7 500 ENABLED 8 500 ENABLED 9 500 ENABLED 10 500 ENABLED 11 500 ENABLED 12 500 ENABLED

Use <TAB> or arrow keys to move. <Enter> to select

Parameter Description

Broadcast Control on All Ports

Allows you to enable/disable broadcast storm control for all ports on the switch.

Threshold The packet-per-second threshold for broadcast packets on the

port. (Default is 500 pps.)

Broadcast Control Enables/disables broadcast control for the port. When enabled,

the switch drops all broadcast packets if the packet-per-second threshold is exceeded. (Default is Enabled.)

44 VH-2402S User Interface VH-2402S

Configuring Bridge MIB Extensions

The Bridge MIB includes extensions for managed devices that support Traffic Classes, Multicast Filtering and Virtual LANs. To configure these extensions, use the Extended Bridge Configuration screen as shown below:

Figure 2-32. Extended Bridge Configuration

Vertical Horizon Local Management -- VH-2402S

Extended Bridge Configuration

Bridge Capability : (Read Only)

Extended Multicast Filtering Services : NO

Traffic Classes : YES

Static Entry Individual Port : YES

Configurable PVID Tagging : YES Local VLAN Capable : NO

Bridge Settings : Traffic Class : TRUE

VLAN Learning : SVL GMRP : DISABLED GVRP : DISABLED

Use <TAB> or arrow keys to move. <Space> to scroll options.

Parameter Description

Bridge Capability

Extended Multicast Filtering Services

Indicates that this switch does not support the filtering of individual multicast addresses based on GMRP (GARP Multicast Registration Protocol). Note that this function is not available for the current firmware release.

Traffic Classes This switch provides mapping of user priorities to multiple traffic

classes. (Refer to 802.1P Configuration.)

Static Entry Individual Port

This switch enables static filtering for unicast and multicast addresses. (Refer to Network Monitor Menu / Static Unicast Address Table Configuration and Static Multicast Address Table Configuration.)

Configurable PVID Tagging

This switch allows you to override the default PVID setting (Port VLAN ID used in frame tags) and its egress status (VLAN-Tagged or Untagged) on each port. (Refer to Port Assignment VLAN Configuration.)

Local VLAN Capable

This switch does not support multiple local bridges (that is, multiple Spanning Trees).

9033645-01 VH-2402S User Interface 45

Bridge Settings

Traffic Class* Multiple traffic classes are supported by this switch as indicated

under Bridge Capabilities. However, you can disable this function by setting this parameter to False.

VLAN Learning As default this switch uses Shared VLAN Learning (SVL),

whereby all ports share one VLAN filtering database. However, you can set the switch to use Independent VLAN Learning (IVL), where each port maintains its own filtering database.

Note that when you change from one method to the other, the switch will automatically reset and the current VLAN configuration will be lost..

GMRP* GARP Multicast Registration Protocol (GMRP) allows network

devices to register endstations with multicast groups. (Note that GMRP is not implemented in the current firmware release.)

The Internet Group Management Protocol (IGMP) is currently used by this switch to provide automatic multicast filtering.

GVRP* GARP VLAN Registration Protocol (GVRP) defines a way for

switches to exchange VLAN information in order to register necessary VLAN members on ports across the network. This function should be enabled to permit VLANs groups which extend beyond the local switch.

* Not implemented in the current firmware release.

Parameter Description

46 VH-2402S User Interface VH-2402S

Configuring Traffic Classes

IEEE 802.1p defines up to 8 separate traffic classes. This switch supports Quality of Service (QoS) by using two priority queues, with weighted fair queuing for each port. You can use the 802.1P Configuration menu to configure the default priority for each port, or to display the mapping for the traffic classes as described in the following sections. Also, refer to Appendix C, “Class of Service” on page 95. .

Figure 2-33. 802.1P Configuration

Vertical Horizon Local Management -- VH-2402S

802.1P Configuration : Selection Menu

802.1P Port Priority Configuration ...

802.1P Port Traffic Class Information ...

<OK>

Use <TAB> or arrows keys to move. <Enter> to select.

9033645-01 VH-2402S User Interface 47

Port Priority Configuration

The default priority for all ingress ports is zero. Therefore, any inbound frames that do not have priority tags will be placed in the low priority output queue. Default priority is only used to determine the output queue for the current port; no priority tag is actually added to the frame. You can use the 802.1P Port Priority Configuration menu to adjust default priority for any port as shown below:

Figure 2-34. 802.1P Port Priority Configuration

Vertical Horizon Local Management -- VH-2402S

802.1P Port Priority Configuration :

Unit 1 Port 1 - 12

Port Default Ingress Number of Egress

User Priority Traffic Class

--------------------------------------------------------- 1 0 2

2 0 2 3 0 2

4 0 2 5 0 2 6 0 2

7 0 2

8 0 2

9 0 2

10 0 2

11 0 2

12 0 2

Use <TAB> or arrow keys to move, other keys to make changes.

Parameter Description

Port Numeric identifier for switch port.

Default Ingress User Priority

Default priority can be set to any value from 0~7, where 0~3 specifies the low priority queue and 4~7 specifies the high priority queue.

Number of Egress Traffic Classes

Indicates that this switch supports two priority output queues.

48 VH-2402S User Interface VH-2402S

802.1P Port Traffic Class Information

This switch provides two priority levels with weighted fair queuing for port egress. This means that any frames with a default or user priority from 0~3 are sent to the low priority queue “0” while those from 4~7 are sent to the high priority queue “1” as shown in the following screen:

Figure 2-35. 802.1P Port Traffic Class Information

Vertical Horizon Local Management -- VH-2402S

802.1P Port Traffic Class Information

: Unit 1 Port 1 - 12

Port User Priority

0 1 2 3 4 5 6 7

----------------------------------------------------------------- 1 0 0 0 0 1 1 1 1

2 0 0 0 0 1 1 1 1 3 0 0 0 0 1 1 1 1 4 0 0 0 0 1 1 1 1

5 0 0 0 0 1 1 1 1

6 0 0 0 0 1 1 1 1 7 0 0 0 0 1 1 1 1 8 0 0 0 0 1 1 1 1

9 0 0 0 0 1 1 1 1 10 0 0 0 0 1 1 1 1 11 0 0 0 0 1 1 1 1

11 0 0 0 0 1 1 1 1

Use <TAB> or arrow keys to move, other keys to make changes.

Parameter Description

Port Numeric identifier for switch port.

User Priority Shows that user priorities 0~3 specify the low priority queue and

4~7 specify the high priority queue.

9033645-01 VH-2402S User Interface 49

Configuring Virtual LANs

You can use the VLAN configuration menu to assign any port on the switch to any of up to 256 LAN groups. In conventional networks with routers, broadcast traffic is split up into separate domains. Switches do not inherently support broadcast domains. This can lead to broadcast storms in large networks that handle a lot of IPX and NetBeui traffic. By using IEEE 802.1Q compliant VLANs and GARP VLAN Registration Protocol, you can organize any group of network nodes into separate broadcast domains, confining broadcast traffic to the originating group. This also provides a more secure and cleaner network environment. For more information on how to use VLANs, see Appendix B, “Virtual LANs (VLANs)” on page 91. The VLAN configuration screens are described in the following sections.

802.1Q VLAN Base Information

The 802.1Q VLAN Base Information screen displays basic information on the VLAN type supported by this switch.

Figure 2-36. 802.1Q VLAN Base Information

Vertical Horizon Local Management -- VH-2402S

802.1Q VLAN Base Information

VLAN Version Number : 1

MAX VLAN ID : 2048

MAX Supported VLANs : 256

Current Number of 802.1Q VLANs Configured : 2

<OK>

Return to previous panel.

<Enter> to select.

Parameter Description

VLAN Version Number

The VLAN version used by this switch as specified in the IEEE

802.1Q standard.

MAX VLAN ID Maximum VLAN ID recognized by this switch.

MAX Supported VLANs

Maximum number of VLANs that can be configured on this switch.

Current Number of VLANs Configured

The number of VLANs currently configured on this switch.

50 VH-2402S User Interface VH-2402S

802.1Q VLAN Current Table Information

This screen shows the current port members of each VLAN and whether or not the port supports VLAN tagging. Ports assigned to a large VLAN group that crosses several switches should use VLAN tagging. However, if you just want to create a small port-based VLAN for one or two switches, you can assign ports to the same untagged VLAN (page 53). The current configuration is shown in the following figure.

Figure 2-37. 802.1Q VLAN Current Table Information

Parameter Description

Deleted VLAN Entry Counts

The number of times a VLAN entry has been deleted from this table.

VID The ID for the VLAN currently displayed.

Creation Time The value of sysUpTime (System Up Time) when this VLAN was

created.

Status Shows how this VLAN was added to the switch:

Dynamic GVRP: Automatically learned via GVRP. Permanent: Added as a static entry.

Unit Stack unit.

Current Egress Ports

Shows the ports which have been added to the displayed VLAN group, where “1” indicates that a port is a member and “0” that it is not.

Current Untagged Ports

If a port has been added to the displayed VLAN (see Current Egress Ports), its entry in this field will be “1” if the port is untagged or “0” if tagged.

[Show] Displays the members for the VLAN indicated by the “Sorted by VID”

field.

[More] Displays any subsequent VLANs if configured.

Vertical Horizon Local Management -- VH-2402S

802.1Q VLAN Current Table Information

Deleted VLAN Entry Counts : 0

VID Creation Time Status

------------------------------------------------------------------------------- 1 0 (0 day 0 hr 0 min 0 sec) Dynamic GVRP

Unit Current Egress Ports Current Untagged Ports

1. 100000000000 100000000000 10 100000000000 000000000000 00

2. ------------ ------------ -- ------------ ------------ --

3. ------------ ------------ -- ------------ ------------ --

4. ------------ ------------ -- ------------ ------------ --

Sorted by VID : 1

[Show] [More]

<OK>

Use <TAB> or arrow keys to move. <Enter> to select.

Port 1 Port 13 Port 25

9033645-01 VH-2402S User Interface 51

802.1Q VLAN Static Table Configuration

Use this screen to create a new VLAN or modify the settings for an existing VLAN. You can add/delete port members for a VLAN from any unit in the stack, or prevent a port from being automatically added to a VLAN via the GVRP protocol. (Also, note that all ports can only belong to one untagged VLAN. This is set to VLAN 1 by default, but can be changed via the Port Assignment VLAN Configuration screen on page 53.)

Figure 2-38. 802.1Q VLAN Static Table Configuration

Vertical Horizon Local Management -- VH-2402S

1Q VLAN Static Table Configuration

VID VLAN Name Status

------------------------------------------ 1 Active

Unit Egress Ports Forbidden Egress Ports

1. 111111111111 111111111111 ---- 000000000000 000000000000 ----

2. ------------ ------------ ---- ------------ ------------ ----

3. ------------ ------------ ---- ------------ ------------ ----

4. ------------ ------------ ---- ------------ ------------ ----

Unit Untagged Ports

1. 111111111111 111111111111 ---- VID : 1

2. ------------ ------------ ---- [Show]

3. ------------ ------------ ---- [More]

4. ------------ ------------ ---- [New]

Use <TAB> or arrow keys to move, other keys to make changes.

<Enter> to select.

Parameter Description

VID The ID for the VLAN currently displayed. Range: 1-2048

VLAN Name A user-specified symbolic name for this VLAN.

String length: Up to 8 alphanumeric characters

Status Sets the current editing status for this VLAN as:

Not in Service, Destroy, or Active.

Unit Stack unit.

Egress Ports Set the entry for any port in this field to “1” to add it to the displayed

VLAN, or “0” to remove it from the VLAN.

Forbidden Egress Ports

Prevents a port from being automatically added to this VLAN via GVRP.

Untagged Ports Set the entry for any port in this field to “1” to add it to the displayed

VLAN as an untagged port.

[Show] Displays settings for the specified VLAN.

[More] Displays consecutively numbered VLANs.

[New] Sets up the screen for configuring a new VLAN.

52 VH-2402S User Interface VH-2402S

For example, the following screen displays settings for VLAN 2, which includes tagged ports 1-6, and forbidden port 12. (Note that the dashed lines show that there are no switch units in this system other than Unit 1.)

Figure 2-39. 802.1Q VLAN Static Table Configuration Example

Vertical Horizon Local Management -- VH-2402S

1Q VLAN Static Table Configuration

VID VLAN Name Status

------------------------------------------ 2 Active

Unit Egress Ports Forbidden Egress Ports

1. 111111000000 000000000000 ---- 000000000001 000000000000 ----

2. ------------ ------------ ---- ------------ ------------ ----

3. ------------ ------------ ---- ------------ ------------ ----

4. ------------ ------------ ---- ------------ ------------ ----

Unit Untagged Ports

1. 000000000000 000000000000 ---- VID : 2

2. ------------ ------------ ---- [Show]

3. ------------ ------------ ---- [More]

4. ------------ ------------ ---- [New]

Use <TAB> or arrow keys to move, other keys to make changes.

<Enter> to select.

9033645-01 VH-2402S User Interface 53

Port Assignment VLAN Configuration

Use this screen to configure port-specific settings for IEEE 802.1Q VLAN features.

Figure 2-40. Port Assignment VLAN Configuration

Vertical Horizon Local Management -- VH-2402S

Port Assignment VLAN Configuration

Unit Port PVID 802.1Q Trunk Ingress Filter

-------------------------------------------------------------------------1 1 3 NO TRUE 1 2 3 NO TRUE 1 3 1 NO FALSE 1 4 1 NO FALSE 1 5 1 NO FALSE 1 6 1 NO FALSE 1 7 1 NO FALSE 1 8 1 NO FALSE 1 9 1 NO FALSE 1 10 1 NO FALSE

Unit ID : 1 [Show] Port ID : 1 [More]

Use <TAB> or arrow keys to move, <Space> to scroll options.

Parameter Description

PVID The VLAN ID assigned to untagged frames received on this port.

Use the PVID to assign ports to the same untagged VLAN.

802.1Q Trunk Used to enable/disable the VLAN trunk status for the port. A VLAN Trunk link between two VLAN-aware switches will carry traffic from all VLANs, allowing VLAN tagged frames to maintain their VLAN ID across multiple switches. When enabled, a port joins all configured VLANs and the untagged port VLAN ID (PVID) is set to 4000, a reserved VLAN ID for trunk ports.

Ingress Filter* If set to “True,” incoming frames for VLANs which do not include

this port in their member set will be discarded at the inbound port.

[Show] Displays settings for the specified stack unit and port.

[More] Displays consecutively numbered stack units and ports.

* This control does not affect VLAN independent BPDU frames, such as GVRP or STP. However, it does affect VLAN dependent BPDU frames, such as GMRP.

54 VH-2402S User Interface VH-2402S

Multicast Router Port Information

You can use the Multicast Router Port Information screen to display the ports on this switch attached to a neighboring multicast router/switch for each VLAN ID.

Figure 2-41. Multicast Router Port Information

Vertical Horizon Local Management -- VH-2402S

Multicast Router Port Information

Unit Dynamic Router Port List Unit Static Router Port List

-------------------------------------------------------------------------------------------------------

1 000000000000 000000000000 00-- 1 000000000000 000000000000 00--

Sorted by VID : 1

[Show] [More]

Use <TAB> or arrow keys to move. <Enter> to select

Parameter Description

Unit The stack unit ID.

Dynamic Router Port List

The switch ports that have been automatically listed as being attached to a neighboring multicast router/switch.

Static Router Port List The switch ports that have been manually listed as being

attached to a neighboring multicast router/switch.

Sorted by VID The VLAN ID number used to sort the list.

[Show] Displays settings for the specified VLAN ID and stack unit.

[More] Displays consecutively numbered stack units.

9033645-01 VH-2402S User Interface 55

Static Multicast Router Port Configuration

You can use the Static Multicast Router Port Configuration screen to assign ports that are attached to a neighboring multicast router/switch.

Figure 2-42. Static Multicast Router Port Configuration

Vertical Horizon Local Management -- VH-2402S

Static Multicast Router Port Configuration

Unit Static Multicast Router Port List

---------------------------------------------------------- 1 000000000000 000000000000 00--

Sorted by VID : 1 Unit : 1 Port : 1 [Show] [More] [Add] [Delete]

Use <TAB> or arrow keys to move. <Enter> to select

Parameter Description

Unit The stack unit ID.

Static Multicast Router Port List

A list of the switch ports that have been manually configured as being attached to a neighboring multicast router/switch.

Sorted by VID The VLAN ID number used to sort the list.

[Show] Displays settings for the specified VLAN ID and stack unit.

[More] Displays consecutively numbered stack units.

[Add] Adds a new router port to the current list.

[Delete] Removes a router port from the current list.

56 VH-2402S User Interface VH-2402S

IGMP Member Port Configuration

You can use the IGMP Member Port Configuration screen to assign ports that are attached to hosts who want to receive a specific multicast service.

Figure 2-43. IGMP Member Port Configuration

Vertical Horizon Local Management -- VH-2402S

IGMP Member Port Configuration

Unit Dynamic IGMP Member Port List Static IGMP Member Port List

---------------------------------------------------------------------------------------------------------- 1

VID : Multicast IP : Unit : 1 Port : 1 [Show] [More] [Add] [Delete]

Use <TAB> or arrow keys to move. <Enter> to select

Parameter Description

Unit The stack unit ID.

Dynamic IGMP Member Port List

A list of the switch ports that have been automatically configured as being attached to a IGMP host.

Static IGMP Member Port List

A list of the switch ports that have been manually configured as being attached to a IGMP host.

VID The VLAN ID number used to sort the list.

Multicast IP The IP address for a specific multicast service that is used to sort

the list.

[Show] Displays settings for the specified VLAN ID and stack unit.

[More] Displays consecutively numbered stack units.

[Add] Adds a new host port to the current list.

[Delete] Removes a host port from the current list.

9033645-01 VH-2402S User Interface 57

Port Security Configuration

Use the Port Security Configuration screen to enable and configure port security for the switch. Port Security allows you to configure each port with a list of MAC addresses of devices that are authorized to access the network through that port.

Figure 2-44. Port Security Configuration

Vertical Horizon Local Management -- VH-2402S

Port Security Configuration

MAC Address MAC Address

--------------------------------------------------------------

Secure address count : 0

Unit : 1 Port : 1 MAC : 00-00-00-00-00-00 [Show] [More] [Add] [Delete] Mode:DISABLE [Apply] [Clear]

<OK>

Use <TAB> or arrow keys to move. <Enter> to select

Parameter Description

MAC Address A list of the authorized MAC addresses that can access the

network through the specified port.

Secure Address Count The number of authorized MAC addresses for the specified

port.

Unit The stack unit ID.

Port The port number on the unit.

[Show] Displays authorized MAC addresses for the specified port.

[More] Displays more MAC addresses for the port.

Mode Port security can set to three states; Static, Disable, or

Learning. When set to Static, the switch will drop packets from the port if the source MAC address does not match one of the addresses in the MAC Address list. If set to Learning, the switch will add the source MAC address of all packets received on the port to the authorized MAC Address list.

[Apply] Applies a change of Mode to the port.

MAC A specific MAC address to be added or deleted from the list.

[Add] Adds a new MAC address to the current list.

[Delete] Removes a MAC address from the current list.

[Clear] Clears all the MAC addresses for the current port.

58 VH-2402S User Interface VH-2402S

Monitoring the Switch

The Network Monitor Menu provides access to port statistics, RMON statistics, IP multicast addresses, and the static (unicast) address table. Each of the screens provided by these menus is described in the following sections.

Figure 2-45. Network Monitor Menu

Vertical Horizon Local Management -- VH-2402S

Network Monitor Menu

Port Statistics ... RMON Statistics ... Unicast Address Table ... Multicast Address Registration Table ... IP Multicast Registration Table ... Static Unicast Address Table Configuration ... Static Multicast Address Table Configuration...

<OK>

Use <TAB> or arrow keys to move. <Enter> to select.

Parameter Description

Port Statistics Displays statistics on network traffic passing through the selected

port.

RMON Statistics Displays detailed statistical information for the selected port such

as packet type and frame size counters.

Unicast Address Table

Provides full listing of all unicast addresses stored in the switch, as well as sort, search and clear functions.

Multicast Address Registration Table

Displays the ports that belong to each GMRP Muticast group. (Not implemented in this firmware release.)

IP Multicast Registration Table

Displays the ports that belong to each IP Muticast group.

Static Unicast Address Table Configuration

Allows you to display or configure static unicast addresses.

Static Multicast Address Table Configuration

Allows you to display or configure static GMRP multicast addresses. (Not implemented in this firmware release.)

9033645-01 VH-2402S User Interface 59

Displaying Port Statistics

Port Statistics display key statistics from the Ethernet-like MIB for each port. Error statistics on the traffic passing through each port are displayed. This information can be used to identify potential problems with the switch (such as a faulty port or unusually heavy loading). The values displayed have been accumulated since the last system reboot.

Select the required stack unit, and port or module. The statistics displayed are indicated in the following figure and table.

Figure 2-46. Port Statistics

Vertical Horizon Local Management -- VH-2402S

Port Statistics :

Unit 1 Port 1

EtherLike Counter:

Alignment Errors :0 Late Collisions :0 FCS Errors :0 Excessive Collisions :0

Single Collision Frames :0 Internal MAC Transmit Errors :0 Multiple Collision Frames :0 Carrier Sense Errors :0 SQE Test Errors :0 Frames Too Long :0

Deffered Transmissions :0 Internal MAC Receive Errors :0

[Refresh Statistics] Show port : 1 [Reset Counters] [Show]

Use <TAB> or arrow keys to move. <Enter> to select.

Parameter Description

Alignment Errors For 10 Mbps ports, this counter records alignment errors (mis-

synchronized data packets). For 100 Mbps ports, this counter records the sum of alignment errors and code errors (frames received with rxerror signal).

FCS Errors The number of frames received that are an integral number of

octets in length but do not pass the FCS check.

Single Collision Frames*

The number of successfully transmitted frames for which transmission is inhibited by exactly one collision.

Multiple Collision Frames*

A count of successfully transmitted frames for which transmission is inhibited by more that one collision.

SQE Test Errors* A count of times that the SQE TEST ERROR message is

generated by the PLS sublayer.

Deferred Transmissions*

A count of frames for which the first transmission attempt on a particular interface is delayed because the medium was busy.

Late Collisions The number of times that a collision is detected later than 512 bit-

times into the transmission of a packet.

Excessive Collisions* The number of frames for which transmission failed due to

excessive collisions.

60 VH-2402S User Interface VH-2402S

Displaying RMON Statistics

Use the RMON Statistics screen to display key statistics for each port or media module from RMON group 1. (RMON groups 2, 3 and 9 can only be accessed using SNMP management software.) The following screen displays the overall statistics on traffic passing through each port. RMON statistics provide access to a broad range of statistics, including a total count of different frame types and sizes passing through each port. Values displayed have been accumulated since the last system reboot.

Figure 2-47. RMON Statistics

Internal Mac Transmit Errors*

The number of frames for which transmission failed due to an internal MAC sublayer transmit error.

Carrier Sense Errors* The number of times that the carrier sense condition was lost or

never asserted when attempting to transmit a frame.

Frames Too Long The number of frames received that exceed the maximum

permitted frame size.

Internal Mac Receive Errors*

The number of frames for which reception failed due to an internal MAC sublayer receive error.

* The reported values will always be zero because these statistics are not supported by the internal chip set.

Vertical Horizon Local Management -- VH-2402S

RMON Statistics :

Unit 1 Port 1

Drop Events :0 Jabbers :0

Received Bytes :199299 Collisions :0 Received Frames :15746 64 Byte Frames :37837 Broadcast Frames :3249 65-127 Byte Frames :674356 Multicast Frames :0 128_255 Byte Frames :45430 CRC/Alignment Errors:0 256-511 Byte Frames :20447 Undersize Frames :0 512-1023 Byte Frames :3740

Oversize Frames :0 1024_1518 Byte Frames :35696 Fragments :0

[Refresh Statistics] Show port : 1 [Reset Counters] [Show]

Use <TAB> or arrow keys to move. <Enter> to select.

Parameter Description

9033645-01 VH-2402S User Interface 61

Parameter Description

Drop Events The total number of events in which packets were dropped due to

lack of resources.

Received Bytes Total number of bytes of data received on the network. This

statistic can be used as a reasonable indication of Ethernet utilization.

Received Frames The total number of frames (bad, broadcast and multicast)

received.

Broadcast Frames The total number of good frames received that were directed to

the broadcast address. Note that this does not include multicast packets.

Multicast Frames The total number of good frames received that were directed to

this multicast address.

CRC/Alignment Errors

For 10Mbs ports, the counter records CRC/alignment errors (FCS or alignment errors). For 100Mbs ports, the counter records the sum of CRC/alignment errors and code errors (frame received with rxerror signal).

Undersize Frames The total number of frames received that were less than 64 octets

long (excluding framing bits, but including FCS octets) and were otherwise well formed.

Oversize Frames The total number of frames received that were longer than 1518

octets (excluding framing bits, but including FCS octets) and were otherwise well formed.

Fragments The total number of frames received that were less than 64 octets

in length (excluding framing bits, but including FCS octets) and had either an FCS or alignment error.

Jabbers The total number of frames received that were longer than 1518

octets (excluding framing bits, but including FCS octets), and had either an FCS or alignment error.

Collisions The best estimate of the total number of collisions on this

Ethernet segment.

64 Byte Frames The total number of frames (including bad packets) received and

transmitted that were 64 octets in length (excluding framing bits but including FCS octets).

65-127 Byte Frames The total number of frames (including bad packets) received and

transmitted that were between 65 and 127 octets in length inclusive (excluding framing bits but including FCS octets).

128-255 Byte Frames The total number of packets (including bad packets) received and

transmitted that were between 128 and 255 octets in length inclusive (excluding framing bits but including FCS octets).

1024-1518 Byte Frames

The total number of packets (including bad packets) received and transmitted that were between 1024 and 1518 octets in length inclusive (excluding framing bits but including FCS octets).

62 VH-2402S User Interface VH-2402S

Displaying the Unicast Address Table

The Address Table contains the MAC addresses and VLAN identifier associated with each port (that is, the source port associated with the address and VLAN), sorted by MAC address or VLAN ID. You can search for a specific address, clear the entire address table, or information associated with a specific address, or set the aging time for deleting inactive entries.

Figure 2-48. Unicast Address Table

Vertical Horizon Local Management -- VH-2402S

Unicast Address Table

Aging Time: 300 Dynamic Counts: 139 Static Counts: 0

MAC VID Unit Port Status MAC VID Unit Port Status

-------------------------------------------------------------------------------------------------------00-00-00-AA-AA-06 1 1 1 D 00-00-E8-00-00-96 1 1 1 D 00-00-65-0D-00-D5 1 1 1 D 00-00-E8-00-01-01 1 1 1 D 00-00-C0-A4-63-F9 1 1 1 D 00-00-E8-00-01-02 1 1 1 D 00-00-E2-12-F9-F8 1 1 1 D 00-00-E8-00-E8-03 1 1 1 D 00-00-E2-20-C3-D5 1 1 1 D 00-00-E8-10-00-01 1 1 1 D 00-00-E8-00-00-00 1 1 1 D 00-00-E8-10-00-AB 1 1 1 D 00-00-E8-00-00-02 1 1 1 D 00-00-E8-10-DE-F1 1 1 1 D

Sorted by : MAC + VID Cleared by : MAC + VID VLAN ID : 1 VLAN ID : 1 MAC : 00-00-00-00-00-00 MAC : 00-00-00-00-00-00 [Show] [More] [Clear] [Clear Dynamic]

Use <TAB> or arrow keys to move, other keys to make changes.

Parameter Description

Aging Time Time-out period in seconds for aging out dynamically learned

forwarding information. Range: 10 - 65534 seconds; Default: 300 seconds

Dynamic Counts The number of dynamically learned addresses in the table.

Static Counts The number of static addresses in the table.

MAC The MAC address of a node.

VID The VLAN(s) associated with this address or port.

Unit Switch unit in the stack (1~7).

Port The port whose address table includes this MAC address.

Status Indicates address status as:

D: Dynamically learned, or P: Fixed permanently by SNMP network management software.

[Show] Displays the address table based on specified VLAN ID, and

sorted by primary key MAC or VID.

[More] Scrolls through the entries in the address table.

[Clear] Clears the specified MAC address.

[Clear Dynamic] Clears all dynamically learned MAC addresses in the table.

9033645-01 VH-2402S User Interface 63

Displaying the IP Multicast Registration Table

Use the IP Multicast Registration Table to display all the multicast groups active on this switch, including multicast IP addresses and the corresponding VLAN ID.

Figure 2-49. IP Multicast Registration Table

Vertical Horizon Local Management -- VH-2402S

IP Multicast Registration Table

VID Multicast IP Unit Multicast Group Port Lists Learned by

------------------------------------------------------------------------------------------------ 1 225.1.1.1 1. 000000001100 110000000000 00 IGMP

2. 000000001100 110000000000 00 IGMP

3. 000000001100 110000000000 00 IGMP

4. 000000001100 110000000000 00 IGMP

5 225.1.1.2 1. 000000001100 110000000000 00 IGMP

2. 000000001100 110000000000 00 IGMP

3. 000000001100 110000000000 00 IGMP

4. 000000001100 110000000000 00 IGMP

Sorted by : VID + Multicast IP VID : 1 Multicast IP : 225.1.1.1 [Show] [More]

<OK>

Use <TAB> or arrow keys to move. <Enter> to select

Parameter Description

VID VLAN ID assigned to this multicast group.

Multicast IP IP address for specific multicast services.

Unit Stack unit.

Multicast Group Port Lists

The switch ports registered for the indicated multicast service.

Learned by Indicates if the ports were learned dynamically or via IGMP.

[Show] Displays the address table sorted on VID and then Multicast IP.

[More] Scrolls through the entries in the address table.

64 VH-2402S User Interface VH-2402S

Configuring Static Unicast Addresses

Use the Static Unicast Address Table Configuration screen to manually configure host MAC addresses in the unicast table. You can use this screen to associate a MAC address with a specific VLAN ID and switch port as shown below.

Figure 2-50. Static Unicast Addreeess Table Configuration

Vertical Horizon Local Management -- VH-2402S

Static Unicast Address Table Configuration

VID MAC Address Unit Port Status

------------------------------------------------------------------------------------ 1 00-00-00-E8-43-12 1 1 Permanent

Sorted by : VID + MAC VID : 1 MAC: 00-00-00-00-00-00 VID : 1 Unit : 1 Port : 1 MAC : 00-00-00-00-00-00 Status : Permanent

[Show] [More] [Set]

<OK>

Use <TAB> or arrow keys to move. <Enter> to select

Parameter Description

VID The VLAN group this port is assigned to.

MAC Address The MAC address of a host device attached to this switch.

Unit The switch unit the host device is attached to.

Port The port the host device is attached to.

Status The status for an entry can be set to:

Permanent: This entry is currently in use and will remain

so after the next reset of the switch.

DeleteOnReset: This entry is currently in use and will remain

so until the next reset. Invalid: Removes the corresponding entry. DeleteOnTimeOut: This entry is currently in use and will remain

so until it is aged out. (Refer to Address Table

Aging Time on page 62.) Other: This entry is currently in use but the

conditions under which it will remain so differ

from the preceding values.

[Show] Displays the static address table sorted on VID as the primary key

and MAC address as secondary key.

[More] Scrolls through entries in the static address table.

[Set] Adds the specified entry to the static address table, such as

shown in the following example: VID : 1 MAC : 00-00-00-e8-34-22

Unit : 1 Port : 1 Status : Permanent

9033645-01 VH-2402S User Interface 65

Resetting the System

Select the System Restart Menu under the Main Menu to reset the management agent. The reset screen includes options as shown in the following figure and table.

Figure 2-51. System Restart Menu

Logging Off the System

Use the Exit command under the Main Menu to exit the configuration program and terminate communications with the switch for the current session.

Vertical Horizon Local Management -- VH-2402S

System Restart Menu

Restart Option : POST : YES Reload Factory Defaults : NO Keep IP Setting : NO Keep User Authentication : NO

[Restart]

Use <TAB> or arrow keys to move, <Space> to scroll options.

Parameter Description

POST Runs the Power-On Self-Test

Reload Factory Defaults

Reloads the factory defaults

Keep IP Setting Retains the settings defined in the IP Configuration menu.

Keep User Authentication

Retains the user names and passwords defined in the Console Login Configuration menu.

66 VH-2402S User Interface VH-2402S

9033645-01 Configuring & Monitoring the Switch 67

3. CONFIGURING & MONITORING THE SWITCH

Common Tasks

The switch console menus allow you to modify default switch settings and configure the switch for network management. They also allow you to monitor switch performance and status. See Section 2, “VH-2402S User Interface,” for an overview of the menu hierarchy and a description of all menus. The following sections describe common tasks in setting up and operating the VH-2402S switch using the console menus.

To begin, set operating parameters and make sure the network connections are correct by performing these tasks:

• Setting password protection for the switch to prevent unauthorized access to console menus

• Assigning an IP address for the switch if you plan to manage the switch using SNMP, or if you use Telnet to access the switch

• Checking network configuration status and verifying that network connections are correct

After the switch is installed and operating, you may want to perform any of the following tasks:

• Connecting via Telnet for in-band access to the console menus

• Setting SNMP parameters for management access

• Viewing switch statistics to monitor and evaluate switch performance

and traffic patterns on the network

• Configuring port mirroring

• Downloading a software upgrade

• Configuring Spanning Tree parameters

• Configuring VLANs

• Configuring Class of Service

• Configuring IGMP multicast filtering

• Configuring port operation (enable/disable, port speed, full/half

duplex and flow control)

• Configuring port trunks

• Configuring broadcast storm control

• Configring the Unicast Address table

• Setting a default gateway

• Configuring BootP

68 Configuring & Monitoring the Switch VH-2402S

Setting Password Protection

The VH-2402S switch is factory-configured with administrator access rights to the console menus set to READ/WRITE. This setting allows anyone to use the console menus to modify any operational parameter. To protect the configuration of the switch from unauthorized modification, you should enable password protection to the console menus.

To enter a password, do the following:

1. Select Management Setup Menu from the Main Menu and press [Enter].

2. Select Console Login Configuration and press [Enter].

3. For the “ADMIN” user type, enter a password containing up to 11

alphanumeric characters. Note that the password is not case sensitive.

By factory default, there is no password configured. This means that at the login: prompt, all you have to do is type “admin” for the username and press [Enter] to gain READ/ WRITE access to the console menus. When you configure the password parameter, the factory default setting is deactivated and the new password governs access to the console menus.

If you forget your password, contact your Enterasys Networks Support Representative.

You are automatically logged out from the console menus based on the Lock-out Time setting in the Console Login Configuration Menu. A setting of “0” permits the console menus to remain available indefinitely.

9033645-01 Configuring & Monitoring the Switch 69

Assigning an IP Address

To assign an IP address to the switch, do the following:

1. Select Management Setup Menu from the Main menu.

2. Select Network Configuration and then IP Configuration.

3. Highlight the IP address field and enter the IP address. Press [Enter].

The IP address is now set. The subnet mask is automatically set to correspond to the class of the address entered. If a different mask is used on the network, higlight Subnet Mask and enter the appropriate mask.

Checking Network Configuration Status

To check connection status for the network, do the following:

1. Select Device Control Menu from the Main Menu.

2. Select Port Information and press [Enter].

If a network cable is properly connected to a port, the Link for the port reads UP. If no cable is connected to the port, or if the cable or port is faulty, the Link for the port reads DOWN.

3. If you see a DOWN status for a connected port, plug the cable into

another port on the switch or try another cable.

Connecting via Telnet

You can connect to the VH-2402S switch from a remote location using the Telnet application. This application allows you to establish in-band access to the console menus.

To connect to the VH-2402S switch via Telnet, do the following:

1. Assign an IP address using the Network Configuration Menu.

2. Set a password using the Console Login Configuration Menu.

3. Login to the VH-2402S switch via Telnet using the configured IP

address and the password.

70 Configuring & Monitoring the Switch VH-2402S

Setting SNMP Management Access

Access to the VH-2402S switch through SNMP is controlled by community names. The community names set for the switch must match those used by the SNMP management station for successful communication to occur. Access for community names can be set to READ/WRITE or READ ONLY access. The default “Public” community name allows READ ONLY access to the device via SNMP, whereas the default “Private” community name allows READ/WRITE access.

The VH-2402S switch can send SNMP messages called traps to SNMP management stations when an important event occurs with the switch. The switch allows up to five destinations to be configured for these trap messages to be sent.

To configure SNMP access for the switch, do the following:

1. Select Management Setup Menu from the Main Menu.

2. Select SNMP Configuration Menu.

3. Select SNMP Communities from the menu. Enter the desired

community names (you are permitted to enter from one to 20 characters) and set access to READ/WRITE or READ ONLY.

4. Select IP Trap Managers from the SNMP Configuration Menu.

5. Enter appropriate IP addresses for the Trap destinations.

6. For each Trap destination entered, a corresponding access

community name should be entered.

Viewing Switch Statistics

To view switch statistics, do the following:

1. Select Network Monitor Menu from the Main Menu.

2. Select Port Statistics. Then select the stack unit, and port to display

the main statistical counts for the port.

3. Select RMON Statistics. Then select the stack unit, and port to display detailed statistical counts for the port.

4. On any of the statistics screens, select Reset Counters to clear (zero) the displayed statistical counts and Refresh Counters to refresh (update) the displayed statistical counts.

9033645-01 Configuring & Monitoring the Switch 71

Configuring Port Mirroring

You can mirror the traffic being switched on any port for the purposes of network traffic analysis and connection assurance. When Port Mirroring is enabled, one port becomes a monitor port for any other port within the stack. Note that the source and target ports must be configured within the same VLAN and be operating at the same speed. If the target port is operating at a lower speed, the source port will be forced to drop its operating speed to match that of the target port.

To configure port mirroring, do the following:

1. Select Device Control Menu from the Main Menu.

2. Select Mirror Port Configuration.

3. For the Mirror Source Port, select the stack unit and port number.

4. For the Mirror Target Port, select the stack unit and port number.

5. Set the Status field to ENABLED.

6. Connect a traffic analyzer or RMON probe to the mirroring port.

Downloading a Software Upgrade

You can upgrade the operational software in the VH-2402S switch without physically opening the switch or being in the same location. The software storage sector in the flash memory of the switch is reprogrammable, allowing you to easily download software feature enhancements and problem fixes to the switch from a local or remote location.

Software can be downloaded to the switch in two ways:

• Via the serial port. This procedure is an out-of-band operation that

copies the software through the serial port to the switch. This operation takes approximately 10 minutes and requires minimal configuration.

• Via TFTP download. This procedure uses a TFTP server connected

to the network and downloads the software using the TFTP protocol. A TFTP download is much faster than a serial download, requiring only a few seconds, and can be used to upgrade an switch that is not VH-2402S physically proximate. The disadvantage is that this method requires a TFTP server and additional setup.

72 Configuring & Monitoring the Switch VH-2402S

Downloading Via the Serial Port

A serial download is the easiest method to upgrade the VH-2402S switch software, requiring the least amount of equipment and configuration.

To download switch software via the serial port, do the following:

1. With the console port connected, reset the switch by powering the switch off and then on.

2. After the power-on hardware and software tests are complete, the system initialization screen displays the following message:.

(D)ownload System Image or (S)tart Application: [S]

3. Press “D” to download system firmware. The following message appears:

Select the Firmware Type to Download (1)Runtime (2)POST (3)Mainboard [1]:

4. Select “1” to download the agent software. The following messages appear:

Your Selection: Runtime Code

Download code to FlashROM address 0x02880000

Change Baud Rate to 115200 and Press <ENTER> to Download.

5. Change your baud rate to 115200 bps and press [Enter]. Send the file using the XMODEM protocol from your computer application (the procedure varies depending upon the application used).

When the XMODEM procedure finishes, the following messages are displayed:

XModem Download to DRAM buffer area 0x00200000: ... SUCCESS !

Verifying image in DRAM download buffer 0x00200000... SUCCESS !

Update FlashROM Image at 0x02880000 ... SUCCESS !

(D)ownload another Image or (S)tart Application: [S] s

Change Baud Rate to 19200 and Press <ENTER>.

6. Press “S” to start the user interface, change your baud rate to back to 19200 bps and press [Enter]. The user interface logon screen will then appear.

Downloading Via TFTP

To perform a TFTP download, you must first configure the VH-2402S switch. This consists of programming the switch with an IP address, if this has not already been done, and entering the IP address of the TFTP

9033645-01 Configuring & Monitoring the Switch 73

server and the name of the upgrade file. To program the switch IP address, select the Management Setup Menu from the Main Menu screen, then select Network Configuration.

To download switch software via TFTP, do the following:

1. Select Download Server IP Address from the TFTP Download Menu.

2. Enter the TFTP server IP address and press [Enter].

3. Select Download Filename and enter the file name to be downloaded

from the TFTP server.

4. If necessary, configure the address of an IP gateway to reach the

server from the switch using the Gateway IP field in the Network Configuration: IP Configuration menu.

5. Configure the TFTP server by copying the download file from the

upgrade disk to an appropriate directory and starting the server.

6. Select Process TFTP Download and press [Enter].

To verify that the TFTP download has been successfully completed, note the software version level displayed on the Switch Information screen accessible from the System Information Menu. This number should match the version number that appears on the upgrade disk.

For a TFTP download, the path to the file must be included in its name. For example, if the upgrade file name is filename.bin and it resides in the directory /usr/tftp on the TFTP server, then you must enter the TFTP file name as: “/usr/tftp/filename.bin”.

74 Configuring & Monitoring the Switch VH-2402S

Configuring Spanning Tree Parameters

The VH-2402S switch supports the IEEE 802.1D Spanning Tree Protocol. This protocol allows redundant connections to be created between LAN segments for purposes of fault tolerance. Two or more physical paths between different segments can be created through the switch, with the Spanning Tree Protocol choosing a single path at any given time and disabling all others.

If the chosen path fails for any reason, a disabled alternative is activated, thereby maintaining the connection. See Appendix A, “Spanning Tree Concepts” on page 85 for further information on using the Spanning Tree Protocol in a network.

To configure Spanning Tree Parameters, do the following:

1. Select the Device Control Menu from the Main Menu.

2. Select the Spanning Tree Configuration Menu and then STA Bridge

Configuration.

3. Turn the switch Spanning Tree operation on or off by setting the Spanning Tree Protocol field to ENABLED/DISABLED.

4. Form the Spanning Tree Configuration Menu, select STA Port Configuration.

The Spanning Tree Port Configuration Menu displays. Change the parameters that display in this menu as required.

Configuring Spanning Tree parameters from their default can cause serious deterioration of network performance.

9033645-01 Configuring & Monitoring the Switch 75

Configuring VLANs

A virtual LAN (VLAN) is a group of devices on one or more LANs that are configured such that they can communicate as if they were attached to the same wire. Because VLANs are based on logical instead of physical connections, they are extremely flexible.

The most fundamental benefit of VLAN technology is the ability to create workgroups based on function rather than on physical location or media. For further information, see Appendix B, “Virtual LANs (VLANs)” on page

91.

To configure VLANs, do the following:

1. Select the Device Control Menu from the Main Menu.

2. Select 802.1Q VLAN Static Table Configuration Menu.

3. In the VID and VLAN Name fields, enter an ID number (1-2048) and

a symbolic alphanumeric name (up to 8 characters) to indentify the VLAN.

4. Set the Status field to Active.

5. Under Egress Ports for each stack unit, select ports by entering “1,”

or enter “0” to remove it from the VLAN.

6. Under Forbidden Egress Ports for each stack unit, enter a “1” to

prevent a port from being automatically added to this VLAN via GVRP.

Note that you can enable or disable GVRP for the stack from the Extended Bridge Configuration screen on the Device Control Menu.

7. To configure other VLANs, select New and press [Enter].

Configuring Class of Service

You can configure Class of Service parameters using the 802.1P Port Priority Configuration screen. This screen permits you to configure two priority levels for traffic being forwarded through the switch. During periods of congestion, Class of Service settings ensure that traffic which has been assigned high priority is forwarded through the switch ahead of normal priority traffic. For further information, see Appendix C, “Class of Service” on page 95.”

To configure Class of Service, do the following:

1. Select Device Control Menu from the Main Menu.

2. Select 802.1P Configuration, then 802.1P Port Priority Configuration.

3. For each stack unit, set individual port priorities by entering 0-3 for

the low priority queue or 4-7 for the high priority queue.

Note that the default for all ingress ports is zero.

76 Configuring & Monitoring the Switch VH-2402S

Configuring Port Operation

You can configure switch ports for operational parameters such as autonegotiation, duplex mode, port speed and flow control. The 100Base-FX fiber ports always operate in full duplex mode and 100Mbps speed. Therefore, these two parameters, along with auto-negotiation, are not configurable on these fiber ports.

To configure port operation, do the following:

1. Select Device Control Menu from the Main Menu.

2. Select Port Configuration and press [Enter].

3. Select the stack unit and port number to configure.

4. In the Admin column, select ENABLED. You can also disable the port

due to abnormal behavior or for security reasons.

5. In the Flow Control column, select ENABLED to enable flow control or DISABLED to disable it. When enabled, the switch uses back pressure for half duplex and IEEE 802.3x for full duplex. These flow control methods can also be set directly by selecting BACK_PRESSURE or 802.3X. Note that flow control should not be used of the port is connected to a hub.

6. In the Speed and Duplex column, select AUTO to enable Autonegotiation for the port, or select 1000_FULL, 1000_HALF, 100_FULL, 100_HALF, 10_FULL, or 10_HALF.

If Auto-negotiation is not enabled, the duplex mode and port speed needs to be configured.

9033645-01 Configuring & Monitoring the Switch 77

Configuring the Unicast Address Table

The Unicast Address Table allows you to designate forwarding treatment through the switch for specific MAC addresses, allowing you to maintain the efficiency and security of your network. You can search for a specific MAC address, clear the entire table, or information associated with a specific address, or set the Aging Time for deleteing inactive entries. The switch learns addresses dynamically from incoming packets and builds a table of these addresses along with their associated ports. There are two types of MAC addresses in the forwarding table:

• Dynamic MAC addresses, which are dynamically learned and

removed by the switch based on a time period defined using the Aging Time option.

• Static MAC addresses, which are entered manually, stored in

nonvolatile memory and automatically placed in the address table.

There are five types of status that can be configured for each address in the table:

• Permenant, which means that the MAC address is in use and will

remain so after the next switch reset.

• Delete On Reset, which means that the MAC address is in use and

will remain so until the next switch reset.

• Invalid, which will remove the entry.

• Delete On Time Out, which means that the MAC address is in use

and will remain so until it is aged out.

• Other, which means that the MAC address is in use but the

conditions under which it will remain so differ from the preceding values.

To configure the Unicast Address Table, do the following:

1. Select Network Monitor Menu from the Main Menu.

2. Select Unicast Address Table.

3. As desired, set the Aging Time for the table, or view, search or clear

entries by MAC address or VLAN ID.

To configure a specific MAC address in the table, do the following:

1. From the Network Monitor Menu, select Static Unicast Address Table

Configuration.

2. For the MAC address, specify the VLAN ID, switch port and the

Status (Permanent, Delete On Reset, Invalid, Delete On Time Out, or Other).

3. Highlight the Set field and press [Enter].

78 Configuring & Monitoring the Switch VH-2402S

Setting a Default Gateway

The default Gateway parameter defines the IP address of a router or other network device to which IP packets are to be sent if destined for a subnet outside of that which the switch is operating.

To set a default gateway, do the following:

1. Select Management Setup Menu from the Main Menu.

2. Select Network Configuration and then IP Configuration.

3. In the field Gateway IP,enter the IP address and press [Enter].

Configuring BootP

The BootP protocol allows you to automatically configure the switch’s IP address information. Enabling this feature greatly speeds up device configuration, especially when a large number of devices are installed.

A BootP server must be operating on the network and be properly configured for this option to work. When this option is enabled, the switch tries to obtain an IP address from the BootP server.

To configure BootP, do the following:

1. Select Management Setup Menu from the Main Menu.

2. Select Network Configuration and then IP Configuration.

3. In the IP State field, select BOOTP-GET-IP.

This selection toggles between BOOTP-GET-IP and USER-CONFIG (the default setting).

9033645-01 Configuring & Monitoring the Switch 79

Configuring Port Trunks

You can configure up to five port trunks on a standalone VH-2402S switch, or up to 12 for an entire stack. Each trunk can combine two, three, or four ports, creating an aggregate bandwidth of up to 4Gbps when grouping gigabit ports. Besides balancing the load across each port in the trunk, the additional ports provide redundancy by taking over the load if another port in the trunk should fail.

To configure the port trunks, do the following:

1. Select the Device Control Menu from the Main Menu.

2. Select Port Trunking Configuration.

3. Enter a Trunk ID number from 1 to 12 to identify the trunk.

4. Select up to four ports to configure as one trunk. You can configure

up to five trunks per switch unit. The ports used in a trunk must all be of the same media type (RJ-45, 100 Mbps fiber, or 1000 Mbps fiber). The ports that can be assigned to the same trunk also have certain other restrictions.

The RJ-45 ports used for each trunk must all be on the same internal switch chip. The port groups permitted include:

Group 1 Group 2 Group 3

1,2,3,4, 5,6,7,8, 9,10,11,12, 13,14,15,16 17,18,19,20 21,22,23,24

Only two 100Mbps fiber ports can be configured as a trunk and these must be on the same module. However, 1000Mbps fiber ports can be on any module in the stack.

Note that ports at both ends of a trunk must be configured in an identical manner, including speed, duplex mode, and VLAN assignments.

5. For each Trunk ID, select Enable to enable the trunk.

Note that it is advisable to enable the trunk prior to connecting any cable between the switches to avoid creating a loop.

When using port trunks, remember that:

• Before removing a port trunk via the configuration menu, you must

disable all the ports in the trunk or remove all the network cables. Otherwise, a loop may be created.

• To disable a single link within a port trunk, you should first remove the

network cable, and then disable both ends of the link via the configuration menu. This allows the traffic passing across that link to be automatically distributed to the other links in the trunk, without losing any significant amount of traffic.

80 Configuring & Monitoring the Switch VH-2402S

9033645-01 SNMP Management 81

4. SNMP MANAGEMENT

The SNMP Protocol

SNMP (Simple Network Management Protocol) is a communication protocol designed specifically for the purpose of managing devices or other elements on a network. Network equipment commonly managed with SNMP includes hubs, switches, routers, and host computers. SNMP is typically used to configure these types of devices for proper operation in their network environment, as well as to monitor them to evaluate their performance and detect potential problems.

Managed entities supporting SNMP typically contain software, which runs locally on the device and is referred to as an agent. In Figure 4-1, software in an VH-2402S switch functions as an agent, monitoring and controlling the functionality of the switch.

Figure 4-1. VH-2402S Switches Managed by an

SNMP Management Workstation

A defined set of variables, referred to as managed objects, is maintained by the agent and used to manage the device. These objects are defined in a Management Information Base (MIB) which allows for a standard presentation of the information controlled by the agent over the network.

The software used to access the information maintained by the SNMP agents across a network is referred to as the SNMP Manager, and typically runs on a workstation.

The SNMP manager software uses a MIB specification, equivalent to that which the agent maintains, to read and write objects controlled by the agent for purposes of configuring and monitoring the device. SNMP defines the format of the MIB specifications and the protocol used to access this information.

82 SNMP Management VH-2402S

There are three main operations defined in SNMP:

• GET operations read information from the managed device, such as

those used to obtain status or statistical data.

• SET operations change a functional parameter on the device, such

as those used to configure Port Speed or to initiate a software download. GET and SET operations are initiated only by the manager software, and result in a response by the agent.

• TRAP operations allow the agent to send an unsolicited message to

the manager. This operation is typically used as an alert of a potential problem or a change of status with the device. The Trap Destination parameter in the SNMP Configuration Menu is used to configure the IP addresses of the SNMP Manager to which VH-2402S trap messages are sent.

MIB Objects

A number of standard MIB specifications have been defined for managing network equipment. SNMP compliant devices typically support one or more standard MIBs defined by the Internet Engineering Task Force (IETF), in the form of Request for Comments (RFC) documents.

These MIBs provide a common method of managing devices, such as hubs and switches, and network interfaces, such as Ethernet and token ring. The primary standard MIB, referred to as MIB-II, provides an overall view of the managed agent and must be supported, at least in part, by all SNMP agents. In addition, proprietary MIB extensions are defined by commercial vendors for managing device-specific functions of their products.

The VH-2402S switch supports six standard MIBs:

• RFC 1213 - Management Information Base for Network

Management of TCP/IP based Internets (MIB-II)

• RFC 1573 - Evolution of the Interfaces Group of MIB-II

• RFC 1643 - Definitions of Managed Objects for the Ethernet-like

Interface Types (Ethernet-Like MIB)

• RFC 1493 - Definitions of Managed Objects for Bridges

• RFC 1757 - Remote Network Monitoring Management Information

Base

• IEEE 802.1Q - VLAN Bridge Management (Q-MIB)

The VH-2402S switch also supports Enterasys proprietary MIB extensions.

9033645-01 SNMP Management 83

RFC 1213 (MIB-II)

RFC 1213 provides management of system-level parameters, including TCP/IP protocol-related statistics, IP addressing, and interface statistics for each switch port. MIB-II is the standard MIB defined by RFC 1213. All agent devices operating SNMP are required to support at least part of MIB-II.

This MIB reports information about the protocols and network interfaces supported on the agent itself, as well as other general information. The MIB is divided into a number of groups, each of which corresponds to a specific protocol or set of information. Some groups are defined in other RFC documents.

The groups specifically defined in RFC 1213 and supported by the VH-2402S switch system software are as follows:

• System – General information about the agent system

• Interfaces – Information about the network interfaces of the system

• Address Translation – Interface address information, both MAC level

and network (IP) level

• IP – Statistics and information related to the IP protocol

• ICMP – Statistics and information related to the ICMP protocol

• TCP – Statistics and information related to the TCP protocol

• UDP – Statistics and information related to the UDP protocol

• Transmission – Statistics and information related to the physical

network medium to which the system interfaces (e.g. Ethernet, token ring, etc.).

• SNMP – Statistics and information related to the SNMP protocol

RFC 1573 (Interfaces Evolution MIB)

RFC 1573 clarifies and extends the managed objects of the “Interfaces” group of MIB-II. This MIB takes account of the evolution in interface types and speeds employed in today’s networks.

RFC 1643 (Ethernet-Like MIB)

RFC 1643 provides management and monitoring for the Ethernet-specific aspects of each port on the switch. This is the Ethernet-specific statistics subgroup of the MIB-II Transmission group. This group provides a set of statistics related to Ethernet’s physical level operation. Specifically, error and collision-related statistics are presented.

RFC 1493 (Bridge MIB)

RFC 1493 is a group defined under MIB-II. This MIB deals with the operation of the system as an 802.1D-compliant bridge. Areas of functionality supported by this group include Spanning Tree and forwarding table information and configuration.

84 SNMP Management VH-2402S

RFC 1757 (RMON MIB)

RFC 1757 is a group defined under MIB-II. This MIB provides management for the RMON aspects of the switch. The VH-2402S switch supports four of the nine groups of RMON defined for Ethernet networks on a per port basis.

IEEE 802.1Q (Q-MIB)

This MIB includes the set of managed objects as defined in the IEEE

802.1Q VLAN standard. This MIB provides management for the VLAN

aspects of the switch.

Enterasys Proprietary MIB Extensions

Areas of VH-2402S switch functionality not covered by the standard RFC MIBs are specified in the Enterasys private MIB. This MIB definition is specified separately from MIB-II. Areas covered in this MIB include various system, switch, and port level information.

Compiling MIB Extensions: Enterasys Website

The MIBs supported by the VH-2402S switch must be compiled into the SNMP network management platform before the switch can be managed. The supported MIBs are available using Enterasys’s website at:

http://www.enterasys.com

The four standard MIB specifications listed above with which the VH-2402S switch is compliant are generally available with the SNMP management platform.

9033645-01 Spanning Tree Concepts 85

APPENDIX A. SPANNING TREE CONCEPTS

General

The IEEE 802.1D Spanning Tree Protocol resolves the problems of physical loops in a network by establishing one primary path between any two switches in a network. Any duplicate paths are barred from use and become standby or blocked paths until the original path fails, at which point they can be brought into service.

Spanning Tree Features

The VH-2402S switch meets the requirements of the Spanning Tree Protocol (STP) by performing the following functions:

• Creates a single spanning tree from any arrangement of switching or

bridging elements.

• Compensates automatically for the failure, removal, or addition of

any device in an active data path.

• Achieves port changes in short time intervals, which establishes a

stable active topology quickly with a minimum of network disturbance.

• Uses a minimum amount of communications bandwidth to

accomplish the operation of the Spanning Tree Protocol.

• Reconfigures the active topology in a manner that is transparent to

stations transmitting and receiving data packets.

• Manages the topology in a consistent and reproducible manner

through the use of Spanning Tree Protocol parameters.

The term “switch” is used as an equivalent to “bridge” in this document.

86 Spanning Tree Concepts VH-2402S

Spanning Tree Protocol in a Network

Figure A-1 illustrates the use of three VH-2402S switches to establish an effective Spanning Tree configuration. Switches A, B and C are connected together in a redundant topology (more than one path between two points). If the connection between A and B goes down, the link between A and C becomes active, thereby establishing a path between A and B through switch C. Additionally, if the connection between B and C goes down, the link between A and C becomes active, establishing a path between B and C through switch A.

Figure A-1. Spanning Tree Using VH-2402S Switches

9033645-01 Spanning Tree Concepts 87

Spanning Tree Protocol Parameters

Several configuration parameters control the operation of the Spanning Tree Protocol. Table A-1 describes the parameters and lists the VH-2402S switch default settings for each parameter.

Table A-1. Spanning Tree Protocol Defaults

For detailed information on the operation of the Spanning Tree Protocol, consult Section 4 of IEEE Standard 802.1D, ISO/IEC 10038:1993.

You can cause serious network performance degradation if you do not fully understand Spanning Tree concepts. Be sure to consult personnel experienced with this process prior to configuring Spanning Tree parameters.

Parameter Description Default Value

Bridge Group Address

Unique MAC group address, recognized by all bridges in the network.

Bridge Identifier

Identifier for each bridge. This parameter consists of two parts: a 16-bit bridge priority and a 48-bit network adapter address. Ports are numbered in absolute numbers starting from 1 regardless of their bridge attachment. The network adapter address is the same address as the first port of the bridge.

32768 (bridge priority)

Port Identifier Port Identifier Identifies each port of each bridge, with

an incremental default value given for each port.

Port 1 -32768 Port 9 -32776 Port 17 -32784

Port 2 -32769 Port 10 -32777 Port 18 -32785

Port 3 -32770 Port 11 -32778 Port 19 -32786

Port 4 -32771 Port 12 -32779 Port 20 -32787

Port 5 -32772 Port 13 -32780 Port 21 -32788

Port 6 -32773 Port 14 -32781 Port 22 -32789

Port 7 -32774 Port 15 -32782 Port 23 -32790

Port 8 -32775 Port 16 -32783 Port 24 -32791

Port Priority Indicates the priority of a specific port in relation to

other ports.

128

Cost Component of Each Port

The Spanning Tree Protocol calculates and ensures that an active topology generates minimal cost paths. A value of 100 is generally used for 10Mbps Ethernet networks, a value of 19 for 100Mbps Fast Ethernet, and a value of 4 for 1000Mbps Gigabit Ethernet.

88 Spanning Tree Concepts VH-2402S

Spanning Tree Protocol Operation

When the Spanning Tree Protocol is enabled for the first time or when there is a change in the network topology, such as a failure or the addition or removal of a component, the Spanning Tree Protocol automatically sets up the active topology of the current network.

Communicating Between Bridges

Periodically, all devices running the Spanning Tree Protocol on a network transmit packets to each other “in care of” the Bridge Group Address which all bridges share. When a bridge receives a frame sent to the Bridge Group Address, the bridge’s Spanning Tree Protocol processes the packet. Application software and other LAN segments ignore the packet. Bridges communicate between each other in order to determine the Root Bridge.

Selecting a Root Bridge and Designated Bridges

During communication between bridges, one bridge is determined to have the lowest bridge identifier. This bridge becomes the Root Bridge.

After the Root Bridge has been selected, each LAN segment looks for the bridge that has the lowest cost relative to the Root Bridge. These bridges become Designated Bridges.

Selecting Designated Ports

Each Designated Bridge selects a Designated Port. This port is responsible for forwarding packets to the Root Bridge.

Handling Duplicate Paths

When the active topology of the network is determined, all packets between any two nodes in the network use only one path. Where a duplicate path exists, the non-designated port is put into a blocking state.

Remapping Network Topology

If there is a change in the network topology due to a failure or the removal or addition of any active components, the active topology also changes. This may trigger a change in the state of some blocked ports.

9033645-01 Spanning Tree Concepts 89

There are five (5) states that the ports can be in for spanning tree:

• Blocking: A port in this state does not participate in the transmission

of frames, thus preventing duplication arising through multiple paths existing in the active topology of the bridged LAN.

• Listening: A port in this state is preparing to participate in the

transmission of frames. The transmission of frames is temporarily disabled in order to prevent temporary loops, which may occur in a bridged LAN during the lifetime of this state as the active topology of the bridged LAN changes.

• Learning: A port in this state is preparing to participate in the

transmission of frames.

• Forwarding: A port in this state is participating in the transmission of

frames.

• Disabled: A port in this state does not participate in the transmission

of frames or the operation of the spanning tree process.

90 Spanning Tree Concepts VH-2402S

9033645-01 Virtual LANs (VLANs) 91

APPENDIX B. VIRTUAL LANS (VLANS)

VLANs and Frame Tagging

The VH-2402S switch supports IEEE 802.1Q-compliant virtual LANs (VLANs). This capability provides a highly efficient architecture for establishing VLANs within a network and for controlling broadcast/ multicast traffic between workgroups. Central to this capability is an explicit frame tagging approach for carrying VLAN information between interconnected network devices.

With frame tagging, a four byte data tag field is appended to frames that cross the network. The tag identifies which VLAN the frame belongs to. The tag may be added to the frame by the end station itself or by a network device, such as a switch. In addition to VLAN information, the relative priority of the frame in the network can specified by the tag (see Appendix C, “Class of Service”).

VLANs provide greater network efficiency by reducing broadcast traffic, but also allow you to make network changes without having to update IP addresses or IP subnets. VLANs inherently provide a high level of network security, since traffic must pass through a Layer 3 switch or a router to reach a different VLAN.

This switch supports the following VLAN features:

• Up to 256 VLANs based on the IEEE 802.1Q standard

• Distributed VLAN learning across multiple switches using explicit or

implicit tagging and GARP/GVRP protocol

• Port overlapping, allowing a port to participate in multiple VLANs

• End stations can belong to multiple VLANs

• Passing traffic between VLAN-aware and VLAN-unaware devices

• Two-level priority tagging

• Port trunking with VLANs

VH-2402S VLAN Configuration

VLAN operation on the VH-2402S is enabled by default. Therefore, all frames are transferred internally through the switch with a VLAN tag. This tag may already be on the frame entering the switch, or added to the frame by the switch. VLAN information already existing on frames entering the switch is automatically handled by the switch. The VH-2402S learns VLAN information from tagged frames and appropriately switches frames out the proper ports based on this information. The configuration of VLANs for frames entering the switch without tags must be made by the user of the switch. This configuration can be made either through the console interface or via SNMP.

Assigning Ports to VLANs

Before enabling VLANs for the switch, you must first assign each port to the VLAN groups it will participate in. By default all ports are assigned to VLAN 1 as untagged ports. You should add a port as a tagged port (that is, a port attached to a VLAN-aware device) if you want it to carry traffic for one or more VLANs and the device at the other end of the link also supports VLANs. Then assign the port at the other end of the link to the same VLANs. However, if you want a port on this switch to participate in one or more VLANs, but the device at the other end of the link does not support VLANs, then you must add this port as an untagged port (that is, a port attached to a VLAN-unaware device).

Port-based VLANs are tied to specific ports. The switch’s forwarding decision is based on the destination MAC address and its associated port. Therefore, to make valid forwarding and flooding decisions, the switch learns the relationship of the MAC address to its related port—and thus to the VLAN—at run-time.

VLAN Classification

When the switch receives a frame, it classifies the frame in one of two ways:

• If the frame is untagged, the switch assigns the frame to an

associated VLAN based on the PVID of the receiving port.

• If the frame is tagged, the switch uses the tagged VLAN ID to identify

the port broadcast domain of the frame.

Port Overlapping

Port overlapping can be used to allow access to commonly shared network resources among different VLAN groups, such as file servers or printers. Note that if you implement VLANs which do not overlap, but still need to communicate, you must connect them using a router or Layer 3 switch.

Enterasys VH-2402S Management Manual

Specifications and Main Features

Frequently Asked Questions

User Manual