3Com LinkBuilder MSH User manual

THE LINKBUILDER MSH
4 PORT ETHERNET BRIDGE
MODULE
USER GUIDE
Part No. DUA1860-0AAA01
Published November 1994

3Com Corporation ■5400 Bayfront Plaza ■Santa Clara, California ■95052-8154
© 3Com Corporation, 1994. All rights reserved. No part of this documentation may be reproduced in
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adaptation) without permission from 3Com Corporation.
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from time to time without obligation on the part of 3Com Corporation to provide notification of such
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3Com Corporation provides this documentation without warranty of any kind, either implied or
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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 Corporation, 5400 Bayfront Plaza, Santa Clara, California
95052-8145.
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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’s standard commercial agreement for the
software. Unpublished rights reserved under the copyright laws of the United States.
3Com and LinkBuilder are registered trademarks of 3Com Corporation. Registered trademarks are
registered in the United States, and may or may not be registered in other countries.
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Revision: 01

CONTENTS
ABOUT THIS GUIDE
Introduction ix
How To Use This Guide x
Conventions xi
Special Messages xii
Related Publications xiii
1INTRODUCTION
The LinkBuilder MSH 1-2
The LinkBuilder MSH 4 Port Ethernet Bridge Module 1-3
Managing The Bridge 1-7
Bridging 1-8
Why Use A Bridge? 1-8
Local And Remote Bridges 1-9
Bridge Network Topology 1-10
Learning, Filtering And Forwarding 1-12
Spanning Tree Algorithm And Protocol (STAP) 1-16
Bridge Filters 1-20
What Is Custom Filtering? 1-20
Filter Sets 1-23
Host-to-Host Filtering 1-23
Host-to-Port Filtering 1-24
Port-to-Port Filtering 1-26
Multicast-to-Port Filtering 1-27
Protocol Filtering 1-27
Bit Filtering 1-28
Enabling Custom Filtering 1-29
Simple Network Management Protocol (SNMP) 1-30
Installation And Removal 1-31
Safety Information 1-31
Anti-Static Information 1-31

2GETTING STARTED
Introduction 2-2
The VT100 Management Interface 2-3
The VT100 Bridge Screens 2-4
The VT100 Bridge Menu Map 2-6
Bridge Control Keys 2-8
Simple Bridge Configuration 2-11
Logging On To The LinkBuilder MSH 2-12
Logging On To The Bridge 2-17
Establishing Operator Accounts 2-18
Adding Bridge Information 2-24
Saving And Making Changes Effective 2-26
Erasing All Changes 2-27
Logging Off The Bridge 2-28
IP Address Configuration 2-29
Bridge Connections 2-30
Logging On To The Bridge 2-30
Telnet From The Bridge 2-30
Setting Up Remote Access 2-31
Active 2-32
Next Reset 2-32
Static Routes 2-33
Assigning Host Name / IP Address Pairs 2-36
Using PIN G To Test Connections 2-38
Telnet Log On To Another IP Device From The Bridge 2-42
Talking To Another Bridge User 2-44
Telnet Suspension 2-45
Telnet Log Off 2-45
SNMP Configuration 2-46
Community Administration 2-46
Traps 2-47
Configuring Basic Community Characteristics 2-48
Configuring Community Traps 2-51
3ADVANCED BRIDGING
Introduction 3-2
Spanning Tree Configuration 3-2
Spanning Tree Bridge Configuration 3-3
Spanning Tree Port Configuration 3-6

Custom Filter Configuration 3-9
Setting Up A Host-to-Host Filter Set 3-10
Saving Host-to-Host Filters 3-12
Setting Up A Host-to-Port Filter Set 3-13
Saving Host-to-Port Filters 3-15
Setting Up A Port-to-Port Filter Set 3-16
Saving Port-to-Port Filters 3-17
Setting Up A Multicast-to-Port Filter Set 3-18
Saving Multicast-to-Port Filters 3-19
Setting Up A Protocol Filter Set 3-20
Saving Protocol Filters 3-22
Setting Up A Bit Filter 3-23
Saving Bit Filters 3-26
The Host Filtering Table 3-27
Saving Host Filtering Table And Filter Set Changes 3-29
Saving And Turning Filters On And Off 3-30
4MONITORING
Introduction 4-2
Checking Bridge Statistics 4-3
Rcvd 4-5
Xmit 4-5
Pkts 4-6
Checking Port Activity 4-8
Rcvd 4-10
Xmit 4-10
Pkts 4-11
Viewing Ethernet Statistics 4-12
Received 4-13
Transmitted 4-14
Checking User Access 4-16
5FURTHER CONFIGURATION AND MONITORING
General Help 5-2
Configuration 5-3
Downloading Software Upgrades 5-3
The Permanent Database 5-6
Add Permanent Entry 5-6

Delete Permanent Entry 5-8
Transfer Permanent Entries 5-9
Editing ARP Information 5-10
ARP Parameters 5-10
Add ARP Entry 5-11
Delete ARP Entry 5-12
Changing TCP Characteristics 5-13
Changing Telnet Characteristics 5-14
Port Queuing 5-16
Monitoring 5-17
Viewing General Bridge Information 5-17
Viewing Node Table Information 5-19
Node Table By Address 5-19
Node Table By Hash Bucket 5-20
Viewing The Hardware Configuration 5-22
Viewing Socket Statistics 5-23
Viewing UDP Statistics 5-26
Viewing TCP Information 5-28
TCP Data Statistics 5-28
Packets Received 5-28
Packets Sent 5-30
TCP Connection Statistics 5-31
Viewing IP Statistics 5-33
total packets received 5-33
fragments received 5-34
Viewing ICMP Packet Statistics 5-36
Viewing SNMP Information 5-39
SNMP Statistics 5-39
In Packets 5-39
Out Packets 5-40
SNMP Authentication Statistics 5-42
Viewing ARP Tables 5-43
Viewing Diagnostic Information 5-45
Error Log 5-45
Interactive Diags 5-46
Clear Error Log 5-47

6PROBLEM SOLVING
Spot Checks 6-2
Using The LEDs For Fault Diagnosis 6-3
Correcting Problems 6-4
Network Problems 6-4
PING Or Telnet Problems 6-4
Port Problems 6-5
Performance Problems 6-5
Collision Problems 6-6
STAP Problems 6-6
Filter Problems 6-6
SNMP Problems 6-7
Operation Problems 6-7
Removing And Replacing Equipment 6-8
Spares 6-9
What To Do Next 6-10
ALINK SETTINGS
BTECHNICAL INFORMATION
Electrical B-1
Safety B-1
EMC B-1
Environmental B-1
Reliability B-1
MIB B-2
CTECHNICAL SUPPORT
On-line Technical Services C-1
3Com Bulletin Board Service (3ComBBS) C-1
Ask3Com on CompuServe C-2
3ComFacts Automated Fax Service C-2
3Com Documentation on CD-ROM C-3
Support from Your Network Supplier C-4
Support from 3Com C-4
Returning Products for Repair C-5

INDEX
RADIO FREQUENCY INTERFERENCE STATEMENTS
LIMITED WARRANTY

ABOUT THIS GUIDE
Introduction
This guide contains all the information you need to install and use
the LinkBuilder MSH 4 Port Ethernet Bridge Module. It is written
for the person responsible for the management and maintenance
of the network.
The guide explains:
■How to configure the 4 Port Bridge Module.
■How to identify 4 Port Bridge Module problems and possible
solutions to these problems.
The guide does not explain:
■How to design your network.
■How to install and use the LinkBuilder MSH chassis, its Power
Supply Units, the Management Module or any other modules.
Refer to the guides listed in the Useful Publications section.
The quick reference guide that also accompanies this guide
duplicates some of the information from this guide. As it is
intended for reference use, we recommend that it is stored in the
holder underneath the LinkBuilder MSH chassis.
Throughout this guide, we assume that you are familiar with the
concepts and operation of your Local Area Network. For VT100
and Telnet management, we also assume that you are familiar
with the VT100 management interface.

xABOUT THIS GUIDE
DUA1860-0AAA01
How To Use This Guide
The following list shows where to find specific information:
We recommend that you read Chapter 2 when setting up the
bridge for the first time, in a new environment. Read Chapter 3
for more advanced bridge configuration, if necessary. Read
Chapter 4 when regularly checking the bridge.
If you are looking for: Turn to:
An introduction to the LinkBuilder MSH, the 4 Port
Ethernet Bridge Module, bridging and filtering Chapter 1
How to configure a simple bridge Chapter 2
How to configure an advanced bridge Chapter 3
How to perform simple bridge monitoring Chapter 4
Information about further bridge configuration and
monitoring
Chapter 5
Information about problem solving Chapter 6
Information about link settings Appendix A
Technical information Appendix B
How to obtain technical support Appendix C