3COM SuperStack II 3000 TX User Manual

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SuperStack® II Switch 3000 TX 8 Port

User Guide

Agent Software Version 3.1

http://www.3com.com/

Document No. DUA1694-1AAA04 Published June 1997

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

3Com Ireland reserves the right to revise this documentation and to make changes in content from time to time without obligation on the part of 3Com Ireland to provide notification of such revision or change.

3Com Ireland provides this documentation without warranty of any kind, either implied or expressed, including, but not limited to, the implied warranties of merchantability and fitness for a particular purpose. 3Com may make improvements or changes in the product(s) and/or the program(s) described in this documentation at any time.

UNITED STATES GOVERNMENT LEGENDS:

If you are a United States government agency, then this documentation and the software described herein are provided to you subject to the following restricted rights:

For units of the Department of Defense:

Restricted Rights Legend: Use, duplication, or disclosure by the Government is subject to restrictions as set forth in subparagraph (c) (1) (ii) for Restricted Rights in Technical Data and Computer Software Clause at 48 C.F.R. 52.227-7013. 3Com Ireland, c/o 3Com Limited, 3Com Centre, Boundary Way, Hemel Hempstead, Herts, HP2 7YU, United Kingdom.

For civilian agencies:

Restricted Rights Legend: Use, reproduction, or disclosure is subject to restrictions set forth in subparagraph (a) through (d) of the Commercial Computer Software - Restricted Rights Clause at 48 C.F.R. 52.227-19 and the limitations set forth in 3Com Corporation’s standard commercial agreement for the software. Unpublished rights reserved under the copyright laws of the United States.

3Com Ireland, 1997.

If there is any software on removable media described in this documentation, it is furnished under a license agreement included with the product as a separate document, in the hard copy documentation, or on the removable media in a directory file named LICENSE.TXT. If you are unable to locate a copy, please contact 3Com and a copy will be provided to you.

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

3Com, NetAge, SuperStack, and Transcend are registered trademarks of 3Com Corporation. 3ComFacts is a service mark of 3Com Corporation.

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

Environmental Statement

It is 3Com’s policy to be environmentally friendly in all its operations. This manual is printed on paper that comes from European sustainable, managed forests. The production process for making the pulp has a reduced AOX level (adsorbable organic halogen) resulting in elemental chlorine free paper.

The paper is fully biodegradable and recyclable.

Page 3

ONTENTS

BOUT THIS GUIDE

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

ETTING STARTED

About the Switch 3000 TX 1-1

Summary of Features 1-1 Port Connections 1-2

100BASE-TX Ports 1-2 Plug-in Module 1-2

Switch Operation and Features 1-2

Intelligent Flow Management 1-2 Full Duplex 1-2 Resilient Links 1-2 Virtual LANs (VLANs) 1-3 Spanning Tree Protocol 1-3

PACE 1-3 Network Configuration Examples 1-4 Unit Overview — Front 1-6

100BASE-TX Ports 1-7 LEDs 1-7

Unit Overview — Rear 1-8

Power Socket 1-9 Unit Serial Number 1-9

Redundant Power System Socket 1-9 Reset Button 1-9 Console Port 1-9 Plug-in Module Slot 1-9

Ethernet Address 1-9 Unit Defaults 1-10 Managing the Switch 3000 TX 1-10 Quick Start For SNMP Users 1-11

Entering an IP Address for the Switch 1-11

NSTALLATION AND SETUP

Following Safety Information 2-1 Positioning the Switch 3000 TX 2-1 Configuration Rules for Fast Ethernet 2-2 Configuration Rules with Full Duplex 2-2 Installing the Switch 3000 TX 2-4

Rack Mounting 2-4

Stacking the Switch and Other Units 2-4

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

Connecting a VT100 Terminal 2-7

Connecting a VT100 Terminal Emulator 2-7

Connecting a Workstation Running SLIP 2-8

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ETTING UP FOR MANAGEMENT

Methods of Managing the Switch 3000 TX 3-1

Using the VT100 Management Interface 3-1 Using Telnet 3-2

Managing Over The Network 3-2

IP Addresses 3-2

Obtaining a Registered IP Address 3-3

Navigating the VT100 Screens 3-4

Screen Conventions 3-4 Keyboard Shortcuts 3-5 Correcting Text Entry 3-5

Setting up the Switch for Management 3-6

Logging On 3-6

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

ANAGING THE SWITCH

Setting Up Users 4-2 Creating a New User 4-3 Deleting a User 4-4 Editing User Details 4-5 Assigning Local Security 4-6 Choosing a Switch Management Level 4-7 Setting Up the Switch Unit 4-9 Setting Up the Switch Ports 4-11 Setting Up the Switch Database (SDB) 4-15

The Database View 4-16 Searching the Switch Database 4-17

By MAC Address 4-17

By Port 4-17

3000 TX

Adding an Entry into the SDB 4-17 Deleting an Entry from the SDB 4-17 Specifying that an Entry is Permanent 4-17

Setting Up Resilient Links 4-18

Configuring Resilient Links 4-19 Creating a Resilient Link Pair 4-20 Deleting a Resilient Link Pair 4-20

Viewing the Resilient Links Setup 4-21 Setting Up Traps 4-23 Setting up the Console Port 4-24 Resetting the Switch 3000 TX 4-26 Initializing the Switch 3000 TX 4-27 Upgrading Software 4-28

DVANCED MANAGEMENT

Virtual LANs (VLANs) 5-1

What are VLANs? 5-1

Benefits of VLANs 5-1

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

How VLANs Provide Extra Security 5-2 An Example 5-2 VLANs and the Switch 3000 TX 5-3

The Default VLAN and Moving Ports From the Default

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

5-3 Using AutoSelect VLAN Mode 5-4 Using Non-routable Protocols 5-5 Using Unique MAC Addresses 5-5 Extending VLANs into an ATM Network 5-5

VLAN Configuration Example 5-6

Page 5

Setting Up VLANs on the Switch 5-8

Assigning a Port to a VLAN When Using Port VLAN

Mode 5-9

Specifying that a Port is a VLT port 5-9

Setting Up VLANs Using AutoSelect VLAN Mode 5-10

Specifying Information About the VLAN Server 5-10 Specifying AutoSelect VLAN Mode 5-11

Spanning Tree Protocol 5-12

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

STP Initialization 5-14 STP Stabilization 5-14 STP Reconfiguration 5-14

An Example 5-15 STP Configurations 5-16 Enabling STP on the Switch 5-17 Configuring STP on the Switch 5-18

Configuring the STP Parameters of VLANs 5-18

Configuring the STP Parameters of Ports 5-20

RMON 5-22

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

Statistics 5-22

History 5-22

Alarms 5-22

Hosts 5-23

Hosts Top N 5-23

Matrix 5-23

Filter 5-23

Capture 5-23

Events 5-23 Benefits of RMON 5-24 RMON and the Switch 5-24

RMON Features of the Switch 5-25 About Alarm Actions 5-26 About Default Alarm Settings 5-27 About the Audit Log 5-27

TATUS MONITORING AND STATISTICS

Summary Statistics 6-2 Port Statistics 6-3 Port Traffic Statistics 6-4 Port Error Analysis 6-6 Status Monitoring 6-8 Fault Log 6-9 Remote Polling 6-10

AFETY INFORMATION

Important Safety Information A-1

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

L’information de Sécurité Importante A-4

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

Wichtige Sicherheitsinformationen A-7

Stromversorgung und Sicherung A-8 Steckdose für Redundant Power System A-8 RJ45 Anschlußen A-8

CREEN ACCESS RIGHTS

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ROUBLE-SHOOTING

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

3COM C

LECTRO-MAGNETIC COMPATIBILITY STATEMENTS

ORPORATION LIMITED WARRANTY

OUTS

PIN-

Null Modem Cable D-1 PC-AT Serial Cable D-1 Modem Cable D-2 RJ45 Pin Assignments D-2

WITCH

ECHNICAL SUPPORT

Online Technical Services F-1

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

3000 TX T

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

Access by Analog Modem F-1

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

LOSSARY

ECHNICAL SPECIFICATIONS

NDEX

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BOUT

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

Introduction

This guide provides the information you need to install and configure the Switch 3000 TX 8 Port (3C16941A) with v3.1 agent software.

This guide is intended for use by network administrators who are responsible for installing and setting up network equipment. It assumes a basic working knowledge of Local Area Networks.

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

Throughout this guide, the SuperStack Switch 3000 TX 8 Port is referred to as the Switch 3000 TX, or Switch.

HIS

UIDE

How to Use This Guide

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

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

An overview of the Switch Chapter 1 Information about installing the Switch into your net-

work Information about the methods you can use to

manage the Switch Information about managing the Switch Chapter 4 Information about more advanced management

features; for example VLANs, Spanning Tree and RMON

Information about monitoring the status of the Switch Chapter 6 Safety information Appendix A Information about the access rights for each VT100

screen

Trouble-shooting information Appendix C Information about the pin-outs relating to the Switch Appendix D Information about the Technical Specifications of the

Switch Information about the Technical Support available

from 3Com

Chapter 2

Chapter 3

Chapter 5

Appendix B

Appendix E

Appendix F

Page 8

2 A

BOUT THIS GUIDE

Conventions

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

throughout this guide.

Table 1

Convention Description

Screen displays

The words “enter” and “type”

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

Menu commands

and

Words in type

Words in

bold-face

Text Conventions

buttons

italicized

type

This typeface represents information as it appears on the screen

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

Referred to by their labels, such as “the

■

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

■

[Esc].

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

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

Menu commands or button names appear in italics. Example:

From the

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

Bold text denotes key features.

Help

menu, select

Contents

Table 2

Icon Notice Type Alerts you to...

Notice Icons

Information note

Caution Risk of personal injury, system damage,

Warning Risk of severe personal injury

Important features or instructions

or loss of data

About the Switch 3000 TX

Switching is currently a leading option for increasing performance by providing high speed backbone links and eliminating server bottlenecks. Part of the 3Com SuperStack 3000 TX provides simple, low cost and high performance switched connections to Fast Ethernet networks.

The SuperStack II Switch 3000 TX is a revision of the LinkSwitch 3000 TP.

Summary of Features

The Switch 3000 TX has the following features:

Eight 100BASE-TX ports

■

Plug-in Module slot (Asynchronous Transfer

■

Mode (ATM) and Fast Ethernet) Support for up to 4080 addresses in the Switch

■

Database

■

Store-and-forward forwarding mode ensuring the switch forwards all valid Ethernet frames and discards invalid Ethernet frames such as those with an incorrect CRC

II range of products, the Switch

TARTED

Full Duplex on all fixed ports, and Fast Ethernet

■

Plug-in Module ports Resilient Links

■

Support for 16 Virtual LANs (VLANs)

■

Spanning Tree Protocol (STP) per VLAN

■

PACE (Priority Access Control Enabled) for sup-

■

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

■

Connects to Redundant Power System

■

Integrated network management

■

19-inch rack or stand-alone mounting

■

SmartAgent support:

■

IP and IPX management over SNMP

■

RMON

■

Repeater and Bridge MIB

■

Broadcast storm control

■

Easy software upgrades

■

BOOTP for automatic IP address configuration

■

Local management

■

Intelligent Flow Management for congestion con-

■

trol

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Port Connections

100BASE-TX Ports

The Switch has eight Fast Ethernet 100BASE-TX ports configured as MDIX (cross-over), which provide a 100Mbps connection to other Fast Ethernet devices such as the SuperStack II Switch 1000. The maximum segment length is 100m (328ft) over category 5 twisted pair cable.

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

Plug-in Module

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

Switch Operation and Features

The Switch 3000 TX uses the same algorithm as a conventional 802.1d bridge for filtering, forwarding and learning packet addresses.

Intelligent Flow Management

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

the device from generating more packets until the period of congestion ends.

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

For more information about enabling IFM, refer to

Setting Up the Switch Ports” on page 4-11.

“

Full Duplex

The Switch 3000 TX provides full duplex support for all its fixed ports, and Fast Ethernet Plug-in Module ports. Full duplex allows frames to be transmitted and received simultaneously and, in effect, doubles the potential throughput of a link. In addition, full duplex also supports 100BASE-FX cable runs of up to 2km (6562ft).

Full Duplex can be enabled on all ports, or on individual ports. For more information, refer to “

Setting Up the Switch Unit” and “Setting Up the Switch Ports” in Chapter 4.

Resilient Links

The Switch’s Resilient Link feature enables you to protect critical links and prevent network downtime should those links fail. Setting up resilience ensures that should a main communication link fail, a standby duplicate link immediately and automatically takes over the task of the main link. Each main and standby link pair is referred to as a resilient link pair.

For more information about resilient links, refer to

Setting Up Resilient Links” on page 4-18.

“

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Virtual LANs (VLANs)

The Switch 3000 TX has a Virtual LAN (VLAN) feature which allows you to build your network segments without being restricted by physical connections. A VLAN is defined as a group of location- and topology-independent devices that communicate as if they are on the same physical LAN.

Implementing VLANs on your network has three main advantages:

It eases the change and movement of devices on

■

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

It helps to control broadcast traffic. If an endsta-

■

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

It provides extra security. Devices in VLAN 1 can

■

only communicate with devices in VLAN 2 using a router.

For more information about VLANs, refer to “

Virtual

LANs (VLANs)” on page 5-1.

Spanning Tree Protocol

The Switch 3000 TX supports the Spanning Tree Protocol (STP) which is a bridge-based system for providing fault tolerance on networks. STP allows you to implement parallel paths for network traffic, and ensure that:

About the Switch 3000 TX 1-3

Redundant paths are enabled if the main traffic

■

paths fail

For more information about STP, refer to “

Spanning

Tree Protocol” on page 5-12.

PACE

The Switch 3000 TX supports PACE (Priority Access Control Enabled) technology, which allows multimedia traffic to be carried over standard Ethernet and Fast Ethernet LANs. PACE provides two features:

Implicit Class of Service

■

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

Interactive Access

■

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

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

Setting Up the Switch Ports” in Chapter 4.

“

Setting Up the Switch Unit” and

Redundant paths are disabled when the main

■

paths are operational

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Network Configuration Examples

The following two illustrations show some examples of how the Switch 3000 TX can be used on your network.

Examples of how the Switch 3000 TX can be used in a VLAN-based network are given in Chapter 5

Figure 1-1

The Switch 3000 TX used as a data-center switch

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Network Configuration Examples 1-5

Figure 1-2

Increasing port density with the Switch 3000 TX

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Unit Overview — Front

Figure 1-3

Switch 3000 TX front view

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Unit Overview — Front 1-7

100BASE-TX Ports

The Switch 3000 TX has eight Fast Ethernet 100BASE-TX RJ45 ports configured as MDIX (cross-over), which provide connection to other Fast Ethernet devices such as the SuperStack II Switch

1000. The maximum segment length is 100m (328ft) over category 5 UTP or STP cable.

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

LEDs

Tab le 1- 1 describes the LED behavior on the Switch

3000 TX. For more details about corrective action in the event of a problem, refer to “

C-1.

LEDs” on page

Table 1- 1

LED Color Indicates Port Status LEDs (ports 1 – 8)

Packet Yellow Frames are being transmitted/received

Status Green Link is present; port is enabled.

Plug-in Module Status LEDs (port 9)

Packet Yellow Frames are being transmitted/received

Status Green Link is present; port is enabled.

Unit Status LEDs

Power Green Switch is powered-up. MGMT Green Switch is operating normally.

LED behavior

on the port.

Green flashing Link is present; port is disabled. Off Link is not present.

on the Plug-in Module port.

Green flashing Link is present; port is disabled. Green flashing

(long on, short off) Yellow Plug-in Module has failed its Power On

Yellow flashing Plug-in Module is not recognized. Off Link is not present or the Plug-in Mod-

Green flashing Switch or Plug-in Module is either

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

Refer to the “

OC-3c Module User Guide”.

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

ule is not installed in the Switch.

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

Self Test.

SuperStack II Switch ATM

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Unit Overview — Rear

Figure 1-4

Switch 3000 TX rear view

Page 17

Unit Overview — Rear 1-9

Power Socket

The Switch 3000 TX automatically adjusts to the supply voltage. The fuse is suitable for both 110V A.C. and 220–240V A.C. operation. For information on replacing fuses, refer to Appendix A

Unit Serial Number

You may need this serial number for fault reporting purposes.

Redundant Power System Socket

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

dant Power System (RPS)” on page 2-6.

Connecting a Redun-

Reset Button

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

Switch 3000 TX” on page 4-26.

Resetting the

Plug-in Module Slot

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

When no Plug-in Module is installed, the blanking plate should be secured in place.

Ethernet Address

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

Console Port

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

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Unit Defaults

The following table shows the factory defaults for the Switch 3000 TX features.

Port Status Intelligent Flow

Management Duplex Mode Virtual LANs

PAC E Spanning Tree

(STP) Power On Self Test

(POST) System Alarm

(broadcast bandwidth used)

System Alarm (errors per 10,000 packets)

System Alarm (bandwidth used)

System Alarm (percentage of frames forwarded)

Enabled

Half duplex on all relevant ports

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

Disabled

Normal (Fast Boot)

Enabled

■

High threshold: 20% — Notify and Blip

■

Low threshold: 10% — No action

Enabled

■

High threshold: 2% — Notify

■

Low threshold: 1% — No action

Enabled

■

High threshold: 85% — No action

■

Low threshold: 50% — No action

Enabled

■

High threshold: 85% — No action

■

Low threshold: 50% — No action

Managing the Switch 3000 TX

The menu-driven interface built into the Switch 3000 TX is known as the VT100 interface. You can access it using a VT100 terminal, or a PC using terminal emulation software. You can connect the terminal directly to the Switch or via a modem. You can also access the VT100 interface remotely using Telnet running over the TCP/IP protocol.

Remote management is also possible using a Network Manager from 3Com’s Transcend range. The management protocol is SNMP (Simple Network Management Protocol) and any SNMP-based management facility can manage the unit if the Management Information Base (MIB) is installed correctly in the management workstation. The Switch 3000 TX supports SNMP over both IP and IPX protocols.

product

Page 19

Quick Start For SNMP Users

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

If you are using IP and you have a BOOTP server

■

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

If you are using the IPX protocol, the Switch

■

3000 TX is allocated an IPX address automatically. You can start the SNMP Network Manager and begin managing the Switch.

If you are using IP without a BOOTP server, you

■

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

IP Address for the Switch”, below.

Entering an

Quick Start For SNMP Users 1-11

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

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

admin

(no password is required). Select

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

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

On the Management Setup screen, fill in the follow-

ing fields:

Device IP Address

■

Device SubNet Mask (if necessary)

■

Default Router (if necessary)

■

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

Setting up the Switch for Manage-

ment” on page 3-6.

If you need the Switch 3000 TX to send SNMP traps

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

Setting Up Traps” on page 4-23.

If you need more information about IP and IPX, refer

Managing Over The Network” on page 3-2.

to “

Entering an IP Address for the Switch

Connect a terminal to the console port of the

Switch 3000 TX. The terminal should be configured to 9600 line speed (baud rate), 8 data bits, no parity, and 1 stop bit. Refer to “

Connecting a VT100

Ter mi nal ” on page 2-7.

Press [Return] one or more times until the Main

Banner screen is displayed.

3Com Network Managers such as Transcend Enterprise Manager for Windows may automatically configure the Switch 3000 TX to send traps to them. Please read the documentation supplied with your network management software.

When you have finished with the Management

Setup screen, select OK.

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NSTALLATION AND

Following Safety Information

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

of this guide.

Positioning the Switch 3000 TX

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

When deciding where to site the unit, ensure that:

ETU

Water or moisture cannot enter the case of the

■

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

■

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

No objects are placed on top of the unit.

■

Units are not stacked more than four high if

■

free-standing.

You are able to meet the configuration rules

■

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

■

nected easily. Cabling is away from:

■

Sources of electrical noise such as radios,

■

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

■

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Configuration Rules for Fast Ethernet

The topology rules for 100Mbps Fast Ethernet are slightly different to those for 10Mbps Ethernet.

Figure 2-1

vides examples of how they allow for large-scale Fast Ethernet networks.

The key topology rules are:

■

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

■

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

■

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

illustrates the key topology rules and pro-

Configuration Rules with Full Duplex

With full duplex, the topology rules are:

■

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

■

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

Page 23

Configuration Rules with Full Duplex 2-3

Figure 2-1

Fast Ethernet configuration rules

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NSTALLATION AND SETUP

Installing the Switch 3000 TX

Rack Mounting

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

CAUTION:

before continuing. Remove all self adhesive pads from the underside of the unit, if fitted.

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

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

Figure 2-2

Disconnect all cables from the Switch

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

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

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

Connect network cabling.

Stacking the Switch and Other Units

If the units are free standing, up to four units can be placed on top of one another. If mixing a variety

of SuperStack

II Switch and Hub units, the smaller

units must be positioned at the top.

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

Figure 2-2

Fitting a bracket for rack mounting

Page 25

Wall Mounting

A single Switch can be wall-mounted.

CAUTION:

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

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

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

holes on one side of the unit, as shown in

Figure 2-3

Insert the two screws and tighten with a suitable

screwdriver. Repeat for the other side of the unit.

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

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

Disconnect any cables from the unit before

Figure 2-3

Installing the Switch 3000 TX 2-5

Fitting a bracket for wall mounting

Position the base of the unit against the wall (or

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

Using suitable fixings and screws (not provided),

attach the Switch unit securely to the wall or plywood.

Connect network cabling.

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Powering-Up the Switch

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

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

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

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

to configure the type of POST). For a new Switch that is being installed for the first time, power-up takes approximately 15 seconds.

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

Switch

LEDs” on page 1-7).

Connecting a Redundant Power System (RPS)

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

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

4.8A, excluding a Plug-in Module. Check the documentation supplied with your Plug-in Module for power consumption figures.

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

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

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

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

Page 27

Connecting Equipment to the Console Port

The Switch console port settings are set to:

8 data bits

■

no parity

■

1 stop bit

■

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

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

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

Connecting Equipment to the Console Port 2-7

Connecting a VT100 Terminal

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

Connect one end of the cable to the console port

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

Ensure that your terminal is set to:

8 data bits

■

no parity

■

1 stop bit

■

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

Connecting a VT100 Terminal Emulator

Ensure that the workstation is running a suitable

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

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

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

Ensure that your workstation is set to:

8 data bits

■

no parity

■

1 stop bit

■

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

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Connecting a Workstation Running SLIP

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

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

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

agement Setup” on page 3-9.

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

Switch Man-

Page 29

ETTING

FOR

Methods of Managing the Switch 3000 TX

You can manage the Switch in four ways:

Using the VT100 interface by connecting a VT100

■

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

Using the VT100 interface over a TCP/IP network

■

using a workstation running VT100 terminal emulation and Telnet.

Using the VT100 interface by connecting a work-

■

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

■

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

Using the VT100 Management Interface

The menu-driven user interface built into the Switch is known as the VT100 or local manage- ment interface. The VT100 management interface gives a forms-based structure with pre-defined security levels, enabling access to be restricted to particular users.

ANAGEMENT

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

■

Via the Console Port

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

■

Via a Network Connection

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

— You can access the

— The local man-

The Switch can support up to four management user sessions concurrently (for example, one console port and three Telnet connections).

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Using Telnet

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

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

ment Setup” on page 3-9.

3: S

ETTING UP FOR MANAGEMENT

Switch Manage-

Managing Over The Network

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

Each Network Manager provides its own user interface to the management facilities. 3Com's Tran-

scend facilities for managing the Switch.

range of Network Managers all have

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

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

The Switch supports SNMP over both IP and IPX protocols.

IP Addresses

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

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

191.128.40.120

The IP address can be split into two parts:

■

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

■

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

Page 31

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

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

Obtaining a Registered IP Address

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

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

Managing Over The Network 3-3

Telephone: (1) (703) 742 4777

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

http:/ /www. inte rnic .net

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Navigating the VT100 Screens

Screen Conventions

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

Type o f information

Choice Field

Entry Field [

Button

List Box

Shown on screen as...

♦text♦

text

] Text enclosed in square brackets on the screen is a

monitor manager security

Description

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

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

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

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

[Return] moves the cursor to the next field and actions your selections. The spacebar toggles through the options in a choice field or selects and deselects an entry in

the listbox. Listbox selections will be highlighted. [Down Arrow] moves item by item down the listbox until it reaches the end of the list. At the

end of the list it moves the cursor to the next field. [Ctrl] + [U] moves the cursor one page up the listbox. [Ctrl] + [D] moves the cursor one page down the listbox.

text entry

field. An entry field allows you to

Page 33

Navigating the VT100 Screens 3-5

Keyboard Shortcuts

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

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

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

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

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

[Ctrl] + [R] refreshes the screen.

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

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

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

Correcting Text Entry

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

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

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

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Setting up the Switch for Management

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

“The Simple Book”

ISBN 0-13-812611-9 Published by Prentice Hall

■

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

■

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

■

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

by Marshall T. Rose

Figure 3-1

At your terminal, press [Return] one or more times until the Main Banner is displayed (shown in

Figure 3-1

(baud rate) from these keystrokes and defaults to:

■

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

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

Main Banner

). The console port detects the line-speed

auto-baud 8 data bits no parity 1 stop bit

Logging On

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

Page 35

If you have been assigned a user name and pass-

■

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

■

installation or initialization), use a default user name and password to match your access requirements. The defaults are shown in

Tab le 3- 1

. If you are setting up the Switch for

management, we suggest that you log on first

admin

Setting up the Switch for Management 3-7

Tab le 3 -1

User Name Default

monitor monitor monitor — this user can view, but

manager manager manager — this user can access and

security security security — this user can access and

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

Default Users

Access Level

Password

not change all manageable parameters

change the operational parameters but not special/security features

change all manageable parameters

Figure 3-2

Logon screen

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After Logging On

When you have successfully logged on to the Switch, the Main Menu screen is displayed as shown in Figure 3-3

. From here, you can select the options needed to manage the unit. Refer to the screen map on page 4-1

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

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

Figure 3-3

Main Menu screen

If you are a user with

security

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

■

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

Editing User

Details” on page 4-5.

■

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

■

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

Creating a New User” on page 4-3.

Page 37

Switch Management Setup

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

To access the Setup screen, from the Switch Main Menu screen, select the MANAGEMENT SETUP option. The Setup screen is displayed, as shown in

Figure 3-4

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

Unit Overview — Rear” on page 1-8.

to “

The screen shows the following:

MAC Address

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

Power On Self Test Type

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

Normal,

Fast Boot — a basic confidence check lasting approximately 15 seconds. When the Switch performs a Fast Boot, it carries out the following tests:

Checksum test of boot and system areas of Flash

■

memory System memory tests

■

MAC address verification test

■

Normal / Extended

This

the Switch performs a

Figure 3-4

■

If the field is set to an Extended test which may take up to 3 minutes to complete. When the Switch performs an Extended test, it carries out more extensive system memory tests and ASIC memory tests in addition to the Fast Boot tests. The default setting for the field is

Setting up the Switch for Management 3-9

Management Setup screen

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

Normal

Extended

, the Switch performs

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

Resetting the Switch 3000 TX” on page

4-26).

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

Device IP Address

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

Device SubNet Mask

If you are using IP, enter a

suitable network mask. For a Class B IP address,

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

Default Router

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

BOOTP Select

If BOOTP is

Enabled / Disabled

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

SLIP Address

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

SLIP SubNet Mask

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

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

IPX Network

This field shows the address of the network for this protocol. This address is learned automatically from the local IPX router or Netware file server, and you do not need to change it.

This read-only field shows the node address

Node

of the Switch which is learned automatically.

Status

If this field is set to

Enabled / Disabled

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

Data Link Protocol

This read-only field shows the

name of the IPX data link layer protocol.

SETUP TRAPS

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

Setting Up Traps” on page 4-23.

Page 39

Setting up the Switch for Management 3-11

CONSOLE PORT

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

Setting up the Console

Port” on page 4-24.

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Logging Off

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

Auto Logout

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

3: S

ETTING UP FOR MANAGEMENT

Figure 3-5

Auto Logout screen

The Auto Logout screen (see Figure 3-5

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

Page 41

ANAGING

WITCH

3000 TX

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

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

II Switch ATM OC-3c Module User

Figure 4-1

Screen map

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Setting Up Users

From the Main Menu, select USER ACCESS LEVELS. The User Access Levels screen is displayed as shown in Figure 4-2

From this screen you can access:

■

LOCAL SECURITY screen

set up access levels for users on the Switch.

■

CREATE USER screen

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

■

DELETE USERS screen

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

■

EDIT USER screen

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

ANAGING THE SWITCH

— This allows you to

— This allows you to change

3000 TX

Figure 4-2

User Access Levels screen

Page 43

Creating a New User

These steps assume the User Access Levels screen is displayed.

Select the CREATE USER option. The Create User

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

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

Creating a New User 4-3

The Create User screen shows the following fields:

User Name

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

Password

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

Access Level

Assign an access level for the new

user, as follows:

monitor

■

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

secure monitor

■

manager

■

— access to all the manageable param-

— as

monitor

eters of the Switch, except security features

specialist

■

security

■

— access to all manageable parameters

— as

manager

of the Switch

Figure 4-3

Community String

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

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

Create User screen

By default, a community string

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Deleting a User

These steps assume the User Access Levels screen is displayed.

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

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

Select DELETE USERS.

ANAGING THE SWITCH

3000 TX

Figure 4-4

Delete Users screen

Page 45

Editing User Details

These steps assume the User Access Levels screen is displayed.

Select the EDIT USER option. The Edit User screen is

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

When you have completed the changes, select OK.

The Edit User screen shows the following fields:

Editing User Details 4-5

User Name

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

Old Password

To change the user’s password, you

need to enter the current password in this field.

New Password

This field allows you to enter a new

password for the user.

Confirm Password

Re-enter the new password into

this field.

Community String

This field allows you to enter a

community string for the user.

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

Figure 4-5

Edit User screen

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Assigning Local Security

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

These steps assume the User Access Levels screen is displayed.

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

Fill in the fields as required.

When you have filled in the form, select OK.

The access option are:

Enabled / Disabled

Console Port

to the management facilities via the console port, disable access to the facility for each access level. Console port access for cannot be changed. This prevents accidental disabling of all access levels from management.

Security

3000 TX

To prevent access

is enabled and

Figure 4-6

Local Security screen

Remote Telnet

Telnet is an inse-

Enabled / Disabled

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

Community-SNMP

The Switch

Enabled / Disabled

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

Page 47

Choosing a Switch Management Level

The Switch Management screen allows you to:

Choose between managing a port, the unit, or a

■

VLAN Display screens for setting up the Switch

■

Display a screen for managing the Switch Data-

■

base Display screens for managing resilient links

■

Display screens for managing STP

■

Display screens showing statistics

■

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

Management Level

choose

Figure 4-7

Port

, the screen is displayed similar to

, and all operations that you initialize from

this screen relate to an individual port. If you choose

Unit

, the screen is displayed similar to Figure 4-8 and all operations relate to the Switch unit. If you choose

Figure 4-9

VLAN

, the screen is displayed similar to

, and all operations relate to VLANs.

Port / Unit / VLAN

If you

Choosing a Switch Management Level 4-7

Figure 4-7

Switch Management screen for Port level

Port ID

If you choose to

1 / 2 / 3 ... 7 / 8 / 9

manage the Switch at port level, enter the particular port number into this field before selecting the next screen. Ports 1–8 are the 100BASE-TX ports, and port 9 is the Plug-in Module port at the rear of the unit.

Figure 4-8

Switch Management screen for Unit level

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ANAGING THE SWITCH

3000 TX

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

Spanning Tree Protocol” on page

5-12.

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

SERVER

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

Virtual LANs

(VLANs)” on page 5-1.

Use this button to display statistics screens

STATS

for the level of management you have chosen (port or unit). Refer to Chapter 6

Use this button to display the Unit Database

SDB

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

The Database View” on page

4-16.

RESILIENCE

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

Setting

Up Resilient Links” on page 4-18.

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

Figure 4-9

SETUP

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

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

this chapter. For information about the VLAN Setup screen, refer to “ on page 5-8

Switch Management screen for VLAN level

Use this button to display setup screens for

Setting Up the

Setting Up VLANs on the Switch”

Page 49

Setting Up the Switch Unit

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

The Unit Setup screen is displayed as shown in

Figure 4-10

. The screen shows the following fields:

Setting Up the Switch Unit 4-9

Unit Name

This read-only field shows the type of

device.

sysName

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

Enable / Disable

PACE

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

Implicit Class of Service

■

Figure 4-10

Interactive Access

■

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

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

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

Ports” on page 4-11.

Unit Setup screen

— When two-way multimedia

Setting Up the Switch

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Port / AutoSelect

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

■

Port

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

■

AutoSelect

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

For more information, refer to “

Using AutoSelect

VLAN Mode” on page 5-4.

SDB Ageing Time

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

Setting Up the

Switch Database (SDB)” on page 4-15.

Spanning Tree

This field allows

Enable / Disable

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

5-12

Duplex Mode

Ports

This field allows you to specify the duplex

Spanning Tree Protocol” on page

Half Duplex / Full Duplex on 100M

mode of ports that have Unit Default specified in the Duplex Mode field of in the Port Setup screen. The default setting is Half Duplex. For more infor-

This

mation about Duplex Mode, refer to “

Setting Up

the Switch Ports” on page 4-11.

Full duplex is not supported on a port with Intelligent Flow Management (IFM) enabled. Therefore you cannot set the Duplex Mode field to Full Duplex on 100M Ports if any of the relevant ports have IFM enabled.

Oversize Frames

Forward / Discard

This field allows you to specify whether the Switch forwards encapsulated Token Ring frames from 3Com’s Token Ring products. Set this field to Forward if the Switch is connected to 3Com products which support Token Ring encapsulation (for example, the SuperStack II Switch 2000); otherwise set the field to Discard.

Default RMON Host/Matrix

This

Enable / Disable

field allows you to specify whether Hosts and Matrix RMON sessions are enabled on the Default VLAN. The default setting for this field is Disable. For more information about RMON sessions, refer to “ on page 5-22

Plug-in Module Type

This read-only field displays

RMON”

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

Power Supply

This read-only

Internal / External

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

Page 51

Setting Up the Switch Ports

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

The Port Setup screen is displayed, as shown in

Figure 4-11

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

The Port Setup screen shows the following fields:

Port

. Choose the

Figure 4-11

Setting Up the Switch Ports 4-11

Port Setup screen

Port ID

This read-only field shows the ID of the port

you have chosen to set up.

Media Type

This read-only field shows the media

type of the link connected to this port.

Port Speed

This read-only field shows the speed and duplex mode of the link; HD indicates Half Duplex, FD indicates Full Duplex.

Port State

This field allows you to

Enable / Disable

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

Link State

This read-only

Present / Not Available

field shows the state of the link:

Present

■

Not Available

■

— The port is operating normally

— The link has been lost

Lost Links

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

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

Intelligent Flow Management

Enable / Disable

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

Intelligent Flow Management should be disabled if the port is connected to a repeated segment where the traffic is mainly local to that segment.

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

■

If the Duplex Mode field in this screen is set to Full Duplex, the Intelligent Flow Management field is not displayed

■

In all other cases where the port has full duplex enabled, IFM has no effect

Disable Interactive Access

Yes/ No

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

■

The port is connected to a repeater

■

The port is connected to a device with Interactive Access enabled

For more information about Interactive Access, refer

Setting Up the Switch Unit” on page 4-9.

to “

Enable / Disable

VLT Mode:

This field allows you to specify whether the port is a VLT (Virtual LAN Trunk) port. A Virtual Lan Trunk (or VLT) is a Switch-to-Switch link that carries traffic for multiple VLANs. To create a VLT, the ports at both ends of the link must be VLT ports.

For more information about VLTs, refer to “

VLANs

and the Switch 3000 TX” on page 5-3.

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

Duplex Mode

Default

This field allows you to specify the duplex

Half Duplex / Full Duplex / Unit

mode of the port:

■

Full Duplex

— Full duplex allows frames to be transmitted and received simultaneously and, in effect, doubles the potential throughput of a link. In addition, full duplex also supports 100BASE-FX cable runs of up to 2km (6562ft). You should only enable full duplex on a point-to-point link between the Switch and another device with full duplex support.

■

Half Duplex

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

■

Unit Default

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

Port / AutoSelect /

VLAN Configuration Mode

Unit Default

This field allows you to specify how the

port is placed in a VLAN:

■

Port

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

■

AutoSelect

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

Page 53

Setting Up the Switch Ports 4-13

Unit Default

■

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

For more information, refer to “

Using AutoSelect

VLAN Mode” on page 5-4.

Broadcast Storm Control

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

Rising Threshold%

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

Falling Threshold%

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

none / event / disable port /

Rising Action

disable port/notify / blip / blip port/notify

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

none

■

— no action takes place

event

— an SNMP trap is generated

disable port

— the port is disabled

disable port/notify

■

— the port is disabled and an

SNMP trap is generated

blip

— the broadcast and multicast traffic on the

■

port is blocked for 5 seconds

blip port/notify

■

— the broadcast and multicast traffic on the port is blocked for 5 seconds, and an SNMP trap is generated

user defined

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

none / event / enable /

Falling Action

event + enable

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

none

■

— no action takes place

event

— an SNMP trap is generated

enable

— the port is enabled

event + enable

— the port is enabled and an

SNMP trap is generated

user defined

appears as an option in the Falling Action field, an unrecognized action has been specified using a MIB browser. You cannot select this option.

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

The Switch takes 5–7 seconds to recognize that a

■

broadcast storm is occurring.

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

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

Page 55

Setting Up the Switch Database (SDB)

The Switch maintains a database of device addresses that it receives on its ports. It uses the information in this database to decide whether a frame should be forwarded or filtered. The database holds up to a maximum of 4080 entries; each entry consists of the MAC address of the device and an identifier for the port on which it was received.

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

Database is 90% full

■

Database is 100% full

■

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

Entries are added into the Switch Database in two ways:

The Switch can learn entries. That is, the unit

■

updates the SDB with the source MAC address, and the port identifier on which the source MAC address is seen.

Setting Up the Switch Database (SDB) 4-15

There are three types of entries in the SDB:

■

Ageing entries

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

ting Up the Switch Unit” on page 4-9.

■

Non-ageing entries

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

Setting Up the Switch Unit” on page

4-9.

■

Permanent entries

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

Set-

The system administrator can enter and update

■

entries using a MIB browser, an SNMP Network Manager or the Unit Database View screen described in the following sections.

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The Database View

The Unit Database View screen, as shown in

Figure 4-12

, allows you to view and configure the

Switch Database.

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

The Unit Database View screen shows the following:

ANAGING THE SWITCH

Unit

, then select the SDB button.

3000 TX

Database Entries

This read-only field shows the number of entries currently in the SDB. The database holds a maximum of 4080 addresses.

MAC Address

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

Port Number

If you highlight an entry in the list-

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

Permanent

This field allows you to specify

Yes / N o

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

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

entries.

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

Using AutoSelect VLAN

Mode” on page 5-4.

Figure 4-12

A listbox containing the following three fields:

Port MAC Address

currently stored in the database.

Permanent

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

FIND

database. Refer to “

base” later in this chapter.

REFRESH

it displays the latest information.

INSERT

database.

You cannot insert an entry for a port that uses AutoSelect VLAN Mode.

Unit Database View screen

The port ID for the entry.

The MAC address for the port

Yes / N o

Shows Yes if this entry is

This button lets you locate an entry in the

Searching the Switch Data-

This button refreshes the database so that

This button lets you insert an entry into the

Page 57

Setting Up the Switch Database (SDB) 4-17

DELETE

This button allows you to delete entries

from the database.

You cannot delete an entry associated with a port that uses AutoSelect VLAN Mode.

Searching the Switch Database

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

By MAC Address

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

In the MAC Address field, type in the MAC address

you are trying to locate. Select FIND. The port ID is displayed in the Port

Number field and the entry in the listbox is highlighted with an asterisk (*).

By Port

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

Clear the MAC Address field by moving into the

field and pressing the spacebar.

Adding an Entry into the SDB

In the MAC Address field, enter the MAC address of

the device. In the Port Number field, enter the port identifier for

this device. Select whether the entry is permanent or not by

specifying Yes or No in the Permanent field. Select INSERT.

Deleting an Entry from the SDB

In the listbox, highlight the entry you want to delete

and press [Return], or enter the MAC address into the MAC Address field.

Select DELETE.

Specifying that an Entry is Permanent

In the listbox, highlight the entry you want to make

permanent and press [Return], or enter the MAC address into the MAC Address field.

In the Permanent field, specify Yes.

Select INSERT.

In the Port Number field, enter the port ID for which

you want MAC addresses displayed. Select FIND. The listbox shows entries in the data-

base for that port only.

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Setting Up Resilient Links

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

resilient link pair

3000 TX

consists of a

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

■

Up to four resilient link pairs can be configured on a Switch 3000 TX.

■

Resilient links cannot be set up if Spanning Tree (STP) is enabled on the Switch.

■

A resilient link pair can only be set up if:

The ports belong to the same VLAN.

■

Neither of the ports forms part of another

■

resilient link pair.

■

If the main port is a Virtual LAN Trunk (VLT) port, the standby port must also be a VLT port.

■

A resilient link pair must be defined at only one end of the connection.

■

You cannot disable any port that is part of a resilient link pair.

Figure 4-13

Resilient link pair

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

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

Page 59

Configuring Resilient Links

With the Switch Management screen displayed, choose the port to be the main port in the resilient link pair, then select the RESILIENCE button.

The Port Resilience screen is displayed, as shown in

Figure 4-14

. This screen allows you to set up, edit

and delete resilient link pairs.

The screen shows the following:

Setting Up Resilient Links 4-19

Main Port ID

This read-only field shows the ID of

the main port.

Media Type

This read-only field

Twisted Pair / Fiber

indicates the media type connected to the main port.

Available / Not Available / Not Present

Link State

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

Available

■

Not Available

■

Not Present

■

— The port is operating normally

— The resilient link pair is disabled

— The port is not present in the cur-

rent hardware

Standby Port ID

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

Media Type

This read-only field

Twisted Pair / Fiber

indicates the standby port media type.

Figure 4-14

Link State

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

Available

■

Not Available

■

Not Present

■

rent hardware

Standby Links Available

ports that you can configure as standby.

Pair State

Not Available

rent operating state of the resilient link pair:

Active

■

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

Switch Port Resilience screen

Available / Not Available / Not Present

— The port is operating normally

— The resilient link pair is disabled

— The port is not present in the cur-

This listbox shows the

Active / Both Failed / Unknown /

This read-only field displays the cur-

— The resilient link pair is enabled and

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Both Failed

ANAGING THE SWITCH

3000 TX

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

■

Unknown

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

■

Not Available

Active Port

— The resilient link pair is disabled.

Main / Standby

If a main link does

have a higher bandwidth than its standby link, traf-

not

fic is

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

Pair Enable

Enabled / Disabled

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

not

Creating a Resilient Link Pair

Ensure that the port nominated as the standby port is not physically connected to the unit.

Ensure both ports have an identical port security mode configuration and that they are members of the same VLAN.

At the Switch Management screen, select the port to be configured as the main port in the link. Select the RESILIENCE button at the foot of the screen.

Select the standby port from the Standby Links Available listbox or enter the port ID in the Standby Port ID field.

Enable the pair in the Pair Enabled field. Select APPLY.

Connect the cabling for the standby port.

Deleting a Resilient Link Pair

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

Page 61

Viewing the Resilient Links Setup

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

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

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

The following read-only information is displayed:

Unit

and select the

Setting Up Resilient Links 4-21

MAIN Port

This field displays the ID of the port

configured as the main port of the resilient link pair.

STANDBY Port

This field displays the ID of the port configured as the standby port of the resilient link pair.

Active / Both Failed / Unknown / Not

Pair State

Available

This field displays the current state of this

resilient link pair:

Active

■

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

Both Failed

■

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

Unknown

■

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

Not Available

■

— This resilient link pair is disabled.

Figure 4-15

Active Port

displays which port in the resilient link pair is currently carrying traffic:

Main

■

with the main port carrying traffic.

Standby

■

standby port is carrying the traffic. You should rectify the fault as soon as possible. If a main port has a higher bandwidth than the standby port, traffic is automatically switched back provided no loss of link is detected for 2 minutes. Otherwise, switch the traffic back manually by setting the Active Port field in the Port Resilience screen (described on page 4-19

Both Failed

■

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

Unit Resilience Summary screen

Main / Standby / Both Failed

This field

— The pair is operating in its normal state

— The main port has failed and the

) to Main.

— Both ports of the resilient link pair

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Pair Enable

Enabled / Disabled

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

Con-

figuring Resilient Links” on page 4-19.

This button allows you to access the Port Resil-

ience screen for the current resilient link pair.

Page 63

Setting Up Traps

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

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

Setting Up Traps 4-23

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

The Trap Setup screen shows the following:

IP or IPX Address

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

Community String

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

public

Figure 4-16

Throttle

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

Trap Setup screen

This field allows you to specify a throttle

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Setting up the Console Port

From the Management Setup screen, described in

Chapter 3

Console Port Setup screen is displayed, as shown in

Figure 4-17

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

The screen shows the following:

Connection Type

you to select the type of console port connection. Select a modem; DCD Control and DSR Control are enabled. For all other cases, this field should be set

Local

DCD Control

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

, select the CONSOLE PORT button. The

Local / Remote

Remote

if you want to manage the Switch via

Enabled / Disabled

3000 TX

This field allows

This field is only

Figure 4-17

DSR Control

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

Flow Control

Unidirectional / RTS-CTS Bidirectional

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

Auto Config

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

Console Port Setup screen

Enabled / Disabled

XON/XOFF / NONE / RTS-CTS

Enabled / Disabled

This field is only

This field

The Switch can

Page 65

Speed

1200 / 2400 / 4800 / 9 600 / 19200

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

Setting up the Console Port 4-25

Char Size

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

Parity

This read-only field displays the parity

NONE

setting for the Switch. You should configure your terminal to the same setting.

Stop Bit

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

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Resetting the Switch 3000 TX

If you suspect a problem with the Switch 3000 TX, you can reset it.

From the Main Menu, select the RESET option. The Reset screen is displayed, as shown in

Figure 4-18

Select OK.

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

3000 TX

Figure 4-18

Reset screen

CAUTION:

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

Page 67

Initializing the Switch 3000 TX

This screen allows you to perform a reset as described in the previous section, and in addition, returns non-volatile data stored on the unit to its factory defaults (shown on page 1-10 the IP address is not cleared. You should only initialize the Switch if:

The configuration of the device no longer suits

■

your network. Other efforts to solve problems have not suc-

■

ceeded.

To initialize the Switch: From the Main Menu, select the INITIALIZE option.

The Initialize screen is displayed, as shown in

Figure 4-19

Select OK.

CAUTION:

The Switch configuration is cleared from memory and cannot be recovered. After initialization, all user information is lost and only default users are available. All ports are set to their default values, and are therefore enabled and available to all users.

Use the Initialize option with great care.

). Note that

Figure 4-19

VLT ports fail and you are not able to manage

■

the Switch if your management station communicates via the VLT. To avoid this:

Remove the VLT configuration from both ends of

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

Reconfigure the VLT once the initialization is com-

plete.

Initializing the Switch 3000 TX 4-27

Initialize screen

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

Network loops occur if you have set up resilient

■

links. Before initializing the Switch, ensure you have disconnected the cabling for all your standby links.

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Upgrading Software

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

Online Technical Services” on page F-1.

“

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

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

CAUTION: Before attempting to download, note the following:

■

The download only works over the network; it does not work through the console port.

■

The download does not work over a Virtual LAN Trunk (VLT) if you have a Boot software version lower than version 2.0.

■

The download does not work over an ATM link.

To upgrade Switch management software:

From the Main Menu, select the SOFTWARE UPGRADE option.

3000 TX

Figure 4-20

In the File Name field, enter the name of the file that contains the software image to be downloaded to the Switch.

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

In the Server Address field, enter the IP or IPX address of the server containing the software image to be loaded.

Select OK.

Software Upgrade screen

The Software Upgrade screen is displayed, as shown in Figure 4-20

From the Destination field, select Switch (this is the

default).

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

Page 69

DVANCED

Virtual LANs (VLANs)

Setting up Virtual Local Area Networks (VLANs) on the Switch 3000 TX provides you with less time-consuming network administration and more efficient network operation.

ANAGEMENT

With VLANs, you can define your network according to:

■

Departmental

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

groups

— For example, you can

The following sections explain more about the concept of VLANs and explain how they can be implemented on the Switch 3000 TX.

What are VLANs?

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

■

Hierarchical groups

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

■

Usage Groups

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

Benefits of VLANs

Implementing VLANs on your network has three main advantages:

It eases the change and movement of devices on

■

IP networks It helps to control broadcast traffic

■

It provides extra security

■

— For example, you can

— For example, you can have

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How VLANs Ease Change and Movement

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

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

matically if you have 3Com’s Transcend

Enterprise

Manager for Windows (v6.0 and above).

How VLANs Control Broadcast Traffic

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

How VLANs Provide Extra Security

An Example

Figure 5-1 shows a network configured with three

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

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

broadcast domain

— physical LAN seg-

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

Figure 5-1

The concept of VLANs

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Virtual LANs (VLANs) 5-3

VLANs and the Switch 3000 TX

The Switch 3000 TX supports VLANs which consist of a set of switch ports. Each switch port can only belong to one VLAN at a time, regardless of the device to which it is attached.

Each Switch 3000 TX can support up to 16 VLANs. However, you can have more than 16 VLANs in your entire network; to do this, you connect the 16 Switch VLANs to other VLANs using a router.

The Default VLAN and Moving Ports From the Default VLAN

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

It contains all the ports on a new or initialized

■

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

■

work Manager to access the management agent of the unit

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

“Setting Up VLANs on the Switch”

on page 5-8.

Connecting VLANs to a Router

If the devices in a VLAN need to talk to devices in a different VLAN, each VLAN requires a connection to a router. Communication between VLANs can only take place if they are all connected to the router. A VLAN not connected to a router is an isolated VLAN. You need one port for each VLAN connected to the router.

Connecting Common VLANs Between Switch Units

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

Virtual LAN Trunk

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

VLTs can only be used for links between Super-

II Switch 1000, Switch 3000 and Desktop

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

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

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Using AutoSelect VLAN Mode

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

manually

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

automatically

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

AutoSelect VLAN Mode works as follows:

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

Figure 5-3

Having obtained the VLAN membership for the end-

Switch refers to the VLAN Server

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

Figure 5-2

If the relevant port uses AutoSelect VLAN Mode, the

Switch learns the endstation’s MAC address

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

Figure 5-4

Switch places the port in the VLAN

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

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Virtual LANs (VLANs) 5-5

If you use AutoSelect VLAN Mode, note the following:

You need to specify an IP address and community

■

string for the VLAN Server. You cannot use VLAN 15.

■

If a port has been configured as a backbone

■

port or as a VLT port, the port cannot use AutoSelect VLAN Mode.

If a port has a permanent address stored against

■

it in the Switch Database, the port cannot use AutoSelect VLAN Mode.

We recommend that you connect each switch

■

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

For information about how to set up VLANs using AutoSelect VLAN Mode, refer to “Setting Up

VLANs Using AutoSelect VLAN Mode” on page 5-10.

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

Using Unique MAC Addresses

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

Extending VLANs into an ATM Network

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

Switch ATM OC-3c Module User Guide”

SuperStack II

Using Non-routable Protocols

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

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VLAN Configuration Example

The example shown in Figure 5-5 illustrates two VLANs spanning three Switch 1000 units and a basement Switch 3000 TX unit. Each Switch 1000 connects to the basement Switch using a VLT. The attached router allows the two VLANs to communicate with each other.

To set up this configuration:

Use the VT100 screens or VLAN Server database to:

Place ports 1–6 and 13–18 of all the Switch 1000 units in VLAN 1.

Place ports 7–12 and 19–24 of all the Switch 1000 units in VLAN 2.

Connect a port on each Switch 1000 to a port in the Switch 3000 TX.

Use the VT100 screens to:

Specify that each Switch 1000 port connected to the Switch 3000 TX is a backbone port. For more information about backbone ports, refer to the

“SuperStack II Switch 1000 User Guide”

Specify that each Switch 1000 port connected to the Switch 3000 TX is a VLT port.

Specify that each Switch 3000 TX port connected to a Switch 1000 is a VLT port.

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

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

Use the VT100 screens or VLAN Server database to:

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

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

Connect two spare ports on the Switch 3000 TX to the router.

Use the VT100 screens or VLAN Server database to specify that one Switch 3000 TX port connected to the router is placed in VLAN 1, and the other is placed in VLAN 2.

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

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Virtual LANs (VLANs) 5-7

Figure 5-5

VLAN configuration with a Switch 3000 TX as a basement switch

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Setting Up VLANs on the Switch

The VLAN Setup screen allows you to:

■

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

■

View VLAN setup information for the Switch.

To access the VLAN Setup screen:

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

In the Management Level field, choose

Choose the SETUP button. The VLAN Setup screen is displayed as shown in Figure 5-6

VLAN

Figure 5-6

VLAN Setup screen

The screen shows the following:

A listbox containing three fields:

This field allows you to select the ID of the

Port

port that you want to set up.

VLT / Standby / ATM / AutoSelect

Typ e

This field

displays information about the setup of the port:

VLT

— The port is a VLT port. A Virtual LAN

■

Trunk (or VLT) is a Switch-to-Switch link which carries traffic for all the VLANs on each Switch. For more information about VLTs in general, refer to “VLANs and the Switch 3000

TX” on page 5-3. To specify that a port is a

VLT port, refer to “Setting Up the Switch

Ports” on page 4-11.

Standby

■

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

ient Links” on page 4-18.

ATM

■

— The port is an ATM OC-3c Module

port. For more information, refer to the

SuperStack II Switch ATM OC-3c Module User

“

Guide” AutoSelect

■

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

VLAN Mode” on page 5-4. For information

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

Using AutoSelect VLAN Mode” on page 5-10.

VLAN Membership

This field displays the ID of

the VLAN(s) to which the port belongs.

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Virtual LANs (VLANs) 5-9

Port ID

1 / 2 / 3 ... 6 / 7 / 8

This field displays the

ID of the port currently selected in the listbox.

VLAN ID

1 / 2 / 3 ...14 / 15 / 16

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

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

APPLY

This button applies any changes to the VLAN

database.

ATM LEC Setup

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

User Guide”

SuperStack II Switch ATM OC-3c Module

Assigning a Port to a VLAN When Using Port VLAN Mode

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

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

VLAN. Select APPLY.

CAUTION:

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

Specifying that a Port is a VLT port

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

ting Up the Switch Ports” on page 4-11.

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

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Setting Up VLANs Using AutoSelect VLAN Mode

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

■

Specify information about the VLAN Server

■

Specify that the Switch unit, or individual ports on the unit, use AutoSelect VLAN Mode

Specifying Information About the VLAN Server

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

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

In the Management Level field, choose VLAN.

Choose the SERVER button. The VLAN Server screen is displayed, as shown in Figure 5-7

The VLAN Server screen shows the following:

Figure 5-7

Throttle

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

VLAN Server screen

0 ... 99999

This field allows you to specify

VLAN Server IP Address

Enter the IP address of

your VLAN Server in this field.

Backup VLAN Server IP Address

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

VLAN Server Community String

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

public

Poll Period

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

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Specifying AutoSelect VLAN Mode

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

page 4-9

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

Ports” on page 4-11.

Virtual LANs (VLANs) 5-11

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Spanning Tree Protocol

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

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

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

What is STP?

STP is a part of the 802.1d bridge specification defined by the IEEE Computer Society. To explain STP more effectively, the Switch 3000 TX will be defined as a bridge.

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

■

Redundant paths are disabled when the main paths are operational

■

Redundant paths are enabled if the main paths fail

As an example, Figure 5-8

shows a network containing three LAN segments separated by three bridges. With this configuration, each segment can communicate with the others using two paths. This configuration creates loops which cause the network to overload; however, STP allows you to have this configuration because it detects duplicate paths and immediately prevents, or blocks, one of them from forwarding traffic.

Figure 5-9

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

If the link through Bridge C fails, as shown in

Figure 5-10

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

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Spanning Tree Protocol 5-13

Figure 5-8

Figure 5-9

A network that creates loops

Traffic flowing through Bridges C and A

Figure 5-10

Traffic flowing through Bridge B

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How STP Works

STP Initialization

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

■

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

■

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

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

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

STP Stabilization

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

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

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

Tab le 5-1

shows the default path costs for the

Switch 3000 TX.

Table 5- 1

Port Type Duplex Cost

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

100BASE-TX / 100BASE-FX Full 150

Default path costs

Half 12

Half 300

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

blocked

which means that they are prevented from forwarding traffic.

STP Reconfiguration

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

sends out an SNMP trap.

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An Example

Figure 5-11

illustrates part of a network. All bridges have a path cost value assigned to each port, identified by PC=xxx (where xxx is the value). Bridge A is selected by STP as the Root Bridge, because it has the lowest Bridge Identifier. The Designated Bridge Port for LAN A is port 1 on Bridge A. Each of the other four bridges have a Root Port (the port closest to the Root Bridge). Bridge X and Bridge B can offer the same path cost to LAN B. In this case Bridge B's port is chosen as the Designated Bridge Port, because it has the lowest Bridge Identifier. Bridge C's port is chosen as the Designated Bridge Port for LAN C because it offers the lowest Root Path Cost (the route through Bridge C and B has a cost of 200, the route through Bridge Y and B has a cost of

300). You can set the path cost of a bridge port to influence the configuration of a network with a duplicate path.

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

STP Parameters of VLANs” on page 5-18) before

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

Spanning Tree Protocol 5-15

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

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

Figure 5-11

Port costs in a network

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STP Configurations

Figure 5-12 shows two possible STP configurations

using SuperStack II Switch units:

■

Configuration 1 — Redundancy for Backbone Link

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

■

Configuration 2 — Redundancy through Meshed Backbone

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

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Figure 5-12

STP configurations

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Enabling STP on the Switch

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

MANAGEMENT. The Switch Management screen is displayed.

In the Management Level field, choose Unit.

Choose the SETUP button. The Unit Setup screen is

displayed as shown in Figure 5-13 In the Spanning Tree field, specify Enable.

Choose OK.

Spanning Tree Protocol 5-17

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

Figure 5-13

Unit Setup screen

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Configuring STP on the Switch

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

Configuring the STP Parameters of VLANs

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

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

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

In the Management Level field, choose VLAN.

Choose the STP button. The VLAN STP screen is displayed, as shown in Figure 5-14

The VLAN STP screen shows the following:

VLAN ID

1 / 2 / 3 ... 13 / 14 / 15

you to specify the VLAN to be configured.

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

This field allows

Figure 5-14

Topology Changes

number of network topology changes that have occurred in the current VLAN.

Max Age

time (in seconds) that the Switch waits before trying to re-configure the network. If the Switch has not received a BPDU within the time specified in this field, it will try to re-configure the network topology.

Designated Root

Bridge Identifier of the designated Root Bridge.

Hello Time

time delay (in seconds) between the transmission of BPDUs from the Switch.

VLAN STP screen

6 ... 40

1 ... 10

This read-only field shows the

Root Cost

This read-only field shows the path cost

from the Switch to the Root Bridge.

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Spanning Tree Protocol 5-19

Forward Delay

4 ... 30

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

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

Root Port

This read-only field shows the Root Port

of the Switch.

Hold Time

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

Time Since Topology Change

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

Bridge Priority

0 ... 65535

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

32768.

Bridge Max Age

6 ... 40

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

Bridge Hello Time

1 ... 10

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

Bridge Forward Delay

4 ... 30

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

Parameters of Ports” on page 5-20.

This button applies any changes to the STP

APPLY

system.

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

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Configuring the STP Parameters of Ports

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

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

In the Management Level field, choose Port.

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

Choose the STP button. The Port STP screen is displayed as shown in Figure 5-15

The screen shows the following:

Port ID

1 / 2 / 3 ... 7 / 8 / 9

This read-only field

shows the ID of the port to be configured.

STP State

/ Forwarding

Disabled / Listening / Blocking / Learning

This read-only field shows the current

state of the port:

■

Disabled

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

■

Listening

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

Figure 5-15

■

Blocking

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

■

Learning

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

■

Forwarding

packets. BPDUs can also be received and processed.

Port STP screen

— A port in this state does not forward

— A port in this state is preparing to

— A port in this state can forward

Designated Port

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

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Spanning Tree Protocol 5-21

Designated Root

This read-only field shows the

Bridge Identifier of the Root Bridge.

Designated Cost

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

Designated Bridge

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

Fwd Transitions

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

Port Enable

Enable / Disable

This field allows you

to enable or disable the current port.

Priority

0 ... 255

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

Fast Start

Enable/Disable

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

CAUTION:

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

Path Cost

0 ... 65535

This field allows you to spec-

ify the path cost of the port.

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

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

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RMON

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

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

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

What is RMON?

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

A typical RMON setup consists of two components:

■

The RMON probe

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

■

The management workstation

cates with the RMON probe and collects the statistics from it. The workstation does not have to be on the same network as the probe and can

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— An intelligent,

— Communi-

manage the probe by in-band or out-of-band connections.

About the RMON Groups

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

Statistics

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

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

History

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

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

Alarms

The Alarms group provides a versatile, general mechanism for setting thresholds and sampling intervals to generate events on any RMON variable.

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Both rising and falling thresholds are supported, and thresholds can be on the absolute value of a variable or its delta value. In addition, alarm thresholds may be autocalibrated or set manually.

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

Hosts

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

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

Hosts Top N

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

Matrix

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

number of octets, and error packets between the nodes.

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

Filter

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

Capture

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

Events

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

Effective use of the Events group saves you time; rather than having to watch real-time graphs for

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important occurrences, you can depend on the Event group for notification. Through the SNMP traps, events can trigger other actions providing a mechanism for an automated response to certain occurrences.

Benefits of RMON

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

■

RMON improves your efficiency

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

■

RMON allows proactive management

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

■

RMON reduces the traffic load

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

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

RMON and the Switch

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

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

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

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RMON Features of the Switch

Tab le 5- 2 details the RMON support provided by

the Switch.

Tab le 5 -2

RMON Group Support supplied by the Switch Statistics

History

Alarms

RMON support supplied by the Switch

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

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

60-second intervals, 120 historical samples

■

stored 30-second intervals, 120 historical samples

■

stored 30-minute intervals, 96 historical samples

■

stored

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

Bandwidth used

■

Broadcast bandwidth used

■

Percentage of packets forwarded

■

Errors per 10,000 packets

■

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

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

page 5-26

on page 5-27

and “About Default Alarm Settings”

Table 5- 2

RMON support supplied by the Switch

RMON Group Support supplied by the Switch Hosts

Although Hosts is supported by the Switch, there are no Hosts sessions defined on a new or initialized Switch by default.

You can specify that a Hosts session is defined on the Default VLAN; for more information, refer to “Setting Up the Switch Unit”

Hosts Top N

Although Hosts Top N is supported by the Switch, there are no Hosts Top N sessions defined on a new or initialized Switch.

Matrix

Although Matrix is supported by the Switch, there are no Matrix sessions defined on a new or initialized Switch by default.

You can specify that a Matrix session is defined on the Default VLAN; for more information, refer to “Setting Up the Switch Unit”

Filter

The Filter group is not presently supported by the Switch.

Capture

The Capture group is not presently supported by the Switch.

Events

A new or initialized Switch has events defined for use with the default alarm system. Refer to

“About Default Alarm Settings”

more information.

on page 4-9.

on page 5-27 for

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When using the RMON features of the Switch, you should note the following:

■

After the default sessions are created, they have no special status. You can delete or change them as required.

■

The Switch 3000 TX can forward a very large volume of packets per second. The Statistics RMON group is able to monitor every packet, but the other groups sample a maximum of 6000 packets a second.

■

The greater the number of RMON sessions, the greater the burden on the management resources of the Switch; however, the forwarding performance of the Switch is not affected.

About Alarm Actions

You can define up to 700 alarms for the Switch. The actions that you can define for each alarm are shown in Ta bl e 5 -3

Table 5- 3

Action High Threshold Low Threshold

No action. Notify only. Send Trap. Notify and

blip port.

Notify and disable port.

Notify and enable port.

Blip port. Block broadcast and mul-

Disable port. Turn port off. Enable port. Turn port on. Notify and move

resilient port.

Notify and blip device.

Notify and disable device.

Notify and enable device.

Blip device. Block broadcast and mul-

Disable device. Turn all ports on device

Re-enable device.

Alarm Actions

Send Trap. Block broadcast and multicast traffic on the port for 5 seconds.

Send Trap. Turn port off.

Send Trap. Turn port on.

ticast traffic on the port for 5 seconds.

Send Trap. If port is the main port of a resilient link pair then move to standby.

Send Trap. Block broadcast and multicast traffic on all ports for 5 seconds.

Send trap. Turn all ports on device off.

Send Trap. Turn ports back to original state.

ticast traffic on all ports for 5 seconds.

off.

Turn ports back to original state.

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About Default Alarm Settings

A new or initialized Switch has four alarms defined for each port:

Bandwidth used

■

Broadcast bandwidth used

■

Percentage of packets forwarded

■

Errors per 10,000 packets

■

The default values and actions for each of these alarms are given in Tab le 5- 4

Tab le 5 -4

Statistic High

Bandwidth used

Broadcast bandwidth used

Percentage of packets forwarded

Initial settings for the default alarms

Threshold

Value: 85% No action

Value: 20% Notify and blip

Value: 85% No action

Low Threshold Recovery

Valu e: 50% No action

Valu e: 10% No action

Valu e: 50% No action

Samples per average

4 60 seconds

4 20 seconds

4 60 seconds

Period

About the Audit Log

The Switch keeps an audit log of all management user sessions, providing a record of changes to any MIB including the RMON MIB. The log can only be read by users at the SNMP Network Manager.

Each entry in the log contains information in the following order:

Entry number

■

Timestamp

■

User ID

■

Item ID (including qualifier)

■

New value of item

■

There is a limit of 16 records on the number of changes stored. The oldest records are overwritten first.

security

access level using an

Errors per 10,000 packets

Value: 200 Notify

Valu e: 100 No action

4 60 seconds

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Page 97

This chapter describes how to view the current operating status of the Switch, how to display any error information in a fault log and how to carry out a remote poll to check the response of another network device.

It also describes the Statistics screens for the Switch, and advises you on actions to take if you see unexpected values for the statistics. Please note however, that as all networks are different, any actions listed are only suggestions.

Viewing statistics on a regular basis allows you to see how well your network is performing. If you keep simple daily records, you will see trends emerging and notice problems arising before they cause major network faults. This way, statistics can help you get the best out of your network.

TATUS

ONITORING AND

TATISTICS

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Summary Statistics

With the Switch Management screen displayed, choose the management level STATISTICS button. The Summary Statistics screen is displayed, as shown in Figure 6-1

The Summary Statistics screen lists values for the current counter against every port on the Switch and it is refreshed approximately every 2 seconds. Once values have reached approximately 4,000,000,000 they are reset to zero.

Unit

, then select the

To view values for a particular counter, select the first button displayed at the foot of the Summary Statistics screen. Pressing the spacebar toggles through the available counters and as soon as you move away from the button, the screen is refreshed to show values for that counter.

FRAMES RECEIVED

Displays the total number of frames that have been received by the current port, including fragments and frames with errors.

FRAMES TRANSMITTED

Displays the total number of frames successfully transmitted by the current port.

FRAMES FORWARDED

Displays the total number of frames that were received by the current port and forwarded to other ports.

FRAMES FILTERED

Displays the total number of frames that were filtered because the destination station was on the same segment (port) as the source station.

Figure 6-1

MULTI/BROADCAST (RX)

of frames received by the current port that are addressed to a multicast or broadcast address.

MULTI/BROADCAST (TX)

of frames transmitted by the current port that are addressed to a multicast or broadcast address.

ERRORS

have occurred on the current port. Refer to the field description for Errors on page 6-5

CLEAR SCREEN COUNTERS

all counters shown on the screen to zero. Use this button for analysis if you wish to see changes in counters over a short period of time. This button does not clear the counters on the device.

Summary Statistics screen

Displays the total number

Displays the total number of errors that

Use this button to set

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Port Statistics

With the Switch Management screen displayed, choose the management level STATISTICS button. The Port Statistics screen is displayed as shown in Figure 6-2

As well as showing statistics for the port, the Port Statistics screen allows you access to traffic and error counter screens.

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

The Port Statistics screen shows the following:

Port ID

ing.

The ID of the port you are currently manag-

port

, then select the

II Switch ATM

Figure 6-2

Frames Forwarded

average of the proportion of the frames received by the port that are forwarded, expressed as a percentage of all frames received by the port. A sampling period of 1 minute is used.

Port Statistics 6-3

Port Statistics screen

This counter provides a running

Bandwidth Used

This counter provides a running average of the bandwidth used by the port, expressed as a percentage of the maximum bandwidth available for the port. A sampling period of 1 minute is used. The value gives an indication of the general traffic level of the network. A high utilization for single endstation segments is an indication that your network is operating efficiently. However, if multiple endstations are connected to this port and you see values of around 40% you should reconsider the topology of your network because each user will see degraded network performance.

Broadcast Frame Bandwidth

This counter provides a running average of the broadcast frame bandwidth used by the port, expressed as a percentage of the maximum bandwidth available for the port. A sampling period of 5 seconds is used.

Error Frames

This counter provides a running average of the number of errors per 10,000 frames received and is expressed as a percentage. Refer to the field description for Errors on page 6-5

TRAFFIC STATISTICS

Select this button to access

traffic counters for this port.

ERROR ANALYSIS

Select this button to access

error counters for this port.

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Port Traffic Statistics

With the Port Statistics screen displayed, select the TRAFFIC STATISTICS button. The Port Traffic Statistics screen is displayed, as shown in Figure 6-3

The Port Traffic Statistics screen shows the following:

Port ID

The ID of the port you are currently manag-

ing.

Frames Received

The number of valid frames received by the port, including fragments and frames with errors.

Frames Transmitted

The number of frames that have been successfully transmitted by the port, including fragments and frames with errors.

Octets Received

The number of octets received by the port. The calculation includes the MAC header and Cyclical Redundancy Check (CRC), but excludes preamble/Start-of-Frame-Delimiter (SFD). Octet counters are accurate to the nearest 256 octet boundary.

Octets Transmitted

The number of octets transmitted by the port. The calculation includes the MAC header and CRC, but excludes preamble/SFD. Octet counters are accurate to the nearest 256 octet boundary.

Figure 6-3

Multicasts Received

cessfully received that have a multicast destination address. This does not include frames directed to a broadcast address or frames received with errors.

Broadcasts Received

received that have a broadcast destination address. This does not include frames with errors.

Collisions

sions that occurred when transmitting from the unit. Collisions are a normal part of Ethernet operation that occur when two devices attempt to transmit at the same time. A sudden sustained increase in the number of collisions may indicate a problem with a device or cabling on the network, particularly if this is not accompanied by an increase in general network traffic.

Port Traffic Statistics screen

The number of frames suc-

The number of frames

An estimate of the total number of colli-

3COM SuperStack II 3000 TX User Manual

Specifications and Main Features

Frequently Asked Questions

User Manual

Introduction

How to Use This Guide

Conventions

Related Documentation

About the Switch 3000 TX

Summary of Features

Port Connections

Switch Operation and Features

Network Configuration Examples

Unit Overview — Front

100BASE-TX Ports

LEDs

Unit Overview — Rear

Power Socket

Unit Serial Number

Redundant Power System Socket

Reset Button

Plug-in Module Slot

Ethernet Address

Console Port

Unit Defaults

Managing the Switch 3000 TX

Quick Start For SNMP Users

Entering an IP Address for the Switch

Following Safety Information

Positioning the Switch 3000 TX

Configuration Rules for Fast Ethernet

Configuration Rules with Full Duplex

Installing the Switch 3000 TX

Rack Mounting

Stacking the Switch and Other Units

Wall Mounting

Powering-Up the Switch

Connecting a Redundant Power System (RPS)

Connecting Equipment to the Console Port

Connecting a VT100 Terminal

Connecting a VT100 Terminal Emulator

Connecting a Workstation Running SLIP

Methods of Managing the Switch 3000 TX

Using the VT100 Management Interface

Using Telnet

Managing Over The Network

IP Addresses

Navigating the VT100 Screens

Screen Conventions

Keyboard Shortcuts

Correcting Text Entry

Setting up the Switch for Management

Logging On

Switch Management Setup

Logging Off

Auto Logout

Setting Up Users

Creating a New User

Deleting a User

Editing User Details

Assigning Local Security

Choosing a Switch Management Level

Setting Up the Switch Unit

Setting Up the Switch Ports

Setting Up the Switch Database (SDB)

The Database View

Searching the Switch Database

Adding an Entry into the SDB

Deleting an Entry from the SDB

Specifying that an Entry is Permanent

Setting Up Resilient Links

Configuring Resilient Links

Creating a Resilient Link Pair

Deleting a Resilient Link Pair

Viewing the Resilient Links Setup

Setting Up Traps

Setting up the Console Port

Resetting the Switch 3000 TX

Initializing the Switch 3000 TX

Upgrading Software