IBM 8237 User manual

Note
Before using this information and the product it supports, be sure to read the general information under "Notices" on
page C-2 and "Electronic Emission Notices" on page C-3.
1st Edition (May 1997)
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Copyright International Business Machines Corporation 1997. All rights reserved.
Note to U.S. Government Users -- Documentation related to restricted rights -- Use, duplication or disclosure is subject to restrictions
set forth in GSA ADP Schedule Contract with IBM Corp.

Copyright IBM Corp. 1997 iii
Contents
Safety Information ............................................................................................. ix
Lithium Battery ................................................................................................ xiii
About This Manual ........................................................................................... xv
Who Should Read This Manual .......................................................................... xv
How This Manual Is Organized .......................................................................... xv
Technical and Planning References ................................................................... xvi
Chapter 1. Introduction and Planning ........................................................... 1-1
The 8237 ........................................................................................................... 1-1
Features ........................................................................................................ 1-2
Stacks ............................................................................................................ 1-4
Interconnecting Typical Ethernet Hubs .......................................................... 1-4
Interconnecting 8237s ................................................................................... 1-5
Understanding Expansion Ports ........................................................................ 1-6
Media Expansion Ports (MEPs) ..................................................................... 1-6
Fast Expansion Modules (FEMs) .................................................................. 1-6
Back-Pressure Flow Control .......................................................................... 1-7
Understanding Managed Stacks ....................................................................... 1-7
Inter-8237 Communications In Managed Stacks ........................................... 1-7
Why Segment 8237s within a Stack? ............................................................ 1-8
Segmenting 8237s within a Stack ................................................................. 1-8
Linking Segmented 8237s ............................................................................. 1-8
Assigning Backup Ports ..................................................................................... 1-9
Ethernet Planning .............................................................................................. 1-9
Maximum Segment Lengths ........................................................................ 1-10
Four Repeater Limit ..................................................................................... 1-10
Cables and Connectors ................................................................................... 1-10
Cabling Requirements for 10BASE-T Ports ................................................ 1-10
Cabling Requirements for the Expansion Ports ........................................... 1-11
Cabling Requirements for the Management Port ........................................ 1-12
Cabling Requirements for Stack Link .......................................................... 1-12
Protected Vital Configuration Data .................................................................. 1-12
Power Requirements and Characteristics ....................................................... 1-14
Physical Characteristics ................................................................................... 1-14
Operating Environment .................................................................................... 1-15
Space Requirements ................................................................................... 1-15
Environmental Requirements ...................................................................... 1-15
Acoustic Characteristics .................................................................................. 1-15
Documenting Your Installation ......................................................................... 1-16
Rack Document ........................................................................................... 1-16
Stack Document .......................................................................................... 1-16
Setup and Cabling Document ...................................................................... 1-16
Locator Document ....................................................................................... 1-16

iv 8237 Hub Installation and Planning Guide
Chapter 2. Installing the 8237 ......................................................................... 2-1
Before You Begin ............................................................................................... 2-1
Setup ................................................................................................................. 2-1
Rack-Mounting the 8237 ............................................................................... 2-1
Surface-Mounting the 8237 ........................................................................... 2-3
Installing an Expansion Port .......................................................................... 2-4
Installing and Routing Cables ............................................................................ 2-4
Connecting Cables to 10BASE-T Ports and Expansion Ports ....................... 2-4
Connecting Hubs with Stack Link Cables ...................................................... 2-5
Connecting a Modem or a Null-Modem Cable to the Management Port ....... 2-6
Powering on the 8237 ........................................................................................ 2-7
Chapter 3. 8237 Administration ...................................................................... 3-1
The 8237 User Interface Program ..................................................................... 3-1
Management Using Terminal Emulation Software ........................................ 3-1
Establishing a Session with the 8237 ............................................................ 3-2
Model 001 Management Options ....................................................................... 3-4
Set FEM Status ............................................................................................. 3-5
Model 002 and Model 003 Management Options .............................................. 3-6
Exit ................................................................................................................. 3-7
Restart System .............................................................................................. 3-7
System Information ........................................................................................ 3-7
SNMP Configuration ...................................................................................... 3-8
Segment Configuration ................................................................................ 3-13
Hub Configuration ........................................................................................ 3-15
Port Configuration ........................................................................................ 3-19
Port Backups ............................................................................................... 3-25
Port Security Control ................................................................................... 3-27
TFTP Download ........................................................................................... 3-30
Xmodem Download ..................................................................................... 3-31
User Passwords .......................................................................................... 3-32
Management Port Configuration .................................................................. 3-33
Segment Statistics ....................................................................................... 3-34
Hub Statistics ............................................................................................... 3-35
Port Statistics ............................................................................................... 3-37
Understanding the LEDs .................................................................................. 3-43
Getting New Microcode ................................................................................... 3-46
Management Using Telnet ............................................................................... 3-47
Configuring for SLIP .................................................................................... 3-47
Preparing for SNMP Management ................................................................... 3-48
Setting an IP Address Using BootP ............................................................. 3-48
Chapter 4. Troubleshooting, Installation, and Replacement Procedures .. 4-1
Problem Determination ...................................................................................... 4-1
LED Symptom and Fix Listing ....................................................................... 4-1
Hot-Swapping 8237s ..................................................................................... 4-3
Problem Determination Through the Management Port ................................ 4-3
Sample 1 ....................................................................................................... 4-4
Sample 2 ....................................................................................................... 4-5
Sample 3 ....................................................................................................... 4-6
Installation, Removal, and Replacement Procedures ........................................ 4-8
8237 Hub Replacement ................................................................................. 4-8
Expansion Port Installation and Replacement ............................................... 4-8
RMON Daughter Board Installation and Replacement ................................ 4-10

Contents v
SIMM Memory Installation and Replacement .............................................. 4-13
Fan Replacement ........................................................................................ 4-15
8237 Parts Catalog .......................................................................................... 4-17
Available Features for Your 8237 ................................................................ 4-19
RMON Memory SIMM ................................................................................. 4-19
Help and Warranty Service Information ........................................................... 4-20
Step 1: Troubleshooting ............................................................................. 4-20
Step 2: Preparing for the Call ..................................................................... 4-20
Step 3: Placing the Call to IBM ................................................................... 4-20
Appendix A. Cable Pinout Diagrams ............................................................ A-1
Straight-Through 10BASE-T/100BASE-TX Cables .......................................... A-1
Straight-Through 10BASE-T/100BASE-TX Cables for STP ......................... A-2
Crossover 10BASE-T/100BASE-TX Cables ..................................................... A-2
Crossover 10BASE-T/100BASE-TX Cables for STP ................................... A-3
Null-Modem Cable ............................................................................................ A-3
Appendix B. The IBM 8237 Management Information Base ....................... B-1
Appendix C. Product Warranty and Notices ................................................ C-1
Notices .............................................................................................................. C-2
Electronic Emission Notices ............................................................................. C-3
Federal Communications Commission (FCC) Statement ............................. C-3
Industry Canada Class A Emission Compliance Statement ......................... C-3
European Community (CE) Mark of Conformity Statement ......................... C-3
Japanese Voluntary Control Council for Interference (VCCI) Statement ..... C-4
Korean Communications Statement ............................................................. C-4
Trademarks ...................................................................................................... C-4
Glossary of Terms and Abbreviations ......................................................... X-1
Index .............................................................................................................. X-11

vi 8237 Hub Installation and Planning Guide

Copyright IBM Corp. 1997 vii
Figures
1-1. Front View of the IBM 8237 Stackable Ethernet Hub ............................ 1-1
1-2. Hubs B and C are Cascaded from Hub A .............................................. 1-5
2-1. Rotating the Rack-Mounting Brackets ................................................... 2-2
2-2. Attaching the Cable Management Bracket ............................................ 2-3
2-3. 8237 Stack Link Cable (P/N 86H0021) .................................................. 2-5
2-4. Example 8237 Stack .............................................................................. 2-6
2-5. Location of the Management Port .......................................................... 2-6
2-6. Connecting the Power Cord ................................................................... 2-7
3-1. Model 001 Main Menu Panel ................................................................. 3-4
3-2. Model 001 Set FEM Status Panel .......................................................... 3-5
3-3. Model 002 and Model 003 Main Menu Panel ........................................ 3-6
3-4. System Information Panel ...................................................................... 3-7
3-5. SNMP Configuration Panel .................................................................... 3-8
3-6. SNMP Communities Panel .................................................................... 3-9
3-7. IP Trap Managers Panel ...................................................................... 3-10
3-8. IPX Trap Managers Panel ................................................................... 3-11
3-9. Auto-Discovery Configuration Panel .................................................... 3-12
3-10. Segment Configuration Panel .............................................................. 3-13
3-11. Hub Configuration: Hub Selection Menu Panel ................................... 3-15
3-12. Hub Configuration Panel ...................................................................... 3-16
3-13. Hub ID Configuration Panel ................................................................. 3-18
3-14. Port Configuration: Port Selection Menu Panel ................................... 3-19
3-15. Port Configuration Panel (1-8) ............................................................. 3-20
3-16. Port Configuration Panel (9-16) ........................................................... 3-20
3-17. Expansion Port Configuration - MEP Panel ......................................... 3-22
3-18. Expansion Port Configuration - FEM Panel ......................................... 3-23
3-19. Port Backups Panel ............................................................................. 3-25
3-20. Port Intrusion Control: Hub Selection Menu Panel .............................. 3-27
3-21. Port Security Control Panel (1-8) ......................................................... 3-28
3-22. Port Security Control Panel (9-16) ....................................................... 3-28
3-23. TFTP Download Panel ......................................................................... 3-30
3-24. Xmodem Download Panel ................................................................... 3-31
3-25. User Passwords Panel ........................................................................ 3-32
3-26. Management Port Configuration Panel ................................................ 3-33
3-27. Segment Statistics Panel ..................................................................... 3-34
3-28. Hub Statistics: Hub Selection Menu Panel .......................................... 3-35
3-29. Hub Statistics Panel ............................................................................. 3-36
3-30. Port Statistics: Port Selection Menu Panel .......................................... 3-37
3-31. Port Statistics Panel ............................................................................. 3-38
3-32. Expansion Port Statistics - MEP Panel ................................................ 3-40
3-33. Expansion Port Statistics - FEM Panel ................................................ 3-41
3-34. Front View of the 8237 Model 002 or Model 003 Showing the LEDs .. 3-43
3-35. Front View of the 8237 Model 001 Showing the LEDs ........................ 3-43
3-36. A Sample BootP Configuration File ..................................................... 3-48
4-1. Example of Self-Test Results for a Model 001 ...................................... 4-4
4-2. Example of Microcode Failure for a Model 001 ..................................... 4-4
4-3. Example Self-Test Results for Model 002 ............................................. 4-5
4-4. Example Self-Test Results for Model 003 ............................................. 4-6
4-5. Example Microcode Failure for Model 002 and Model 003 ................... 4-7
4-6. Four Expansion Port Types ................................................................... 4-9
4-7. Removing the Top-Cover Screws ........................................................ 4-10

viii 8237 Hub Installation and Planning Guide
4-8. Back View: Removing the Fan-Guard Screws ..................................... 4-11
4-9. Remove the RMON Daughter Board ................................................... 4-11
4-10. SIMM Removal .................................................................................... 4-12
4-11. SIMM Replacement ............................................................................. 4-12
4-12. Removing the Top-Cover Screws ........................................................ 4-13
4-13. Back View: Removing the Fan-Guard Screws ..................................... 4-13
4-14. View of RMON Daughter Board and SIMM ......................................... 4-14
4-15. SIMM Removal .................................................................................... 4-14
4-16. SIMM Replacement ............................................................................ 4-15
4-17. Removing the Mounting-Bracket Screws ............................................. 4-15
4-18. 8237 Back View ................................................................................... 4-16
4-19. Fan Replacement ................................................................................ 4-16
4-20. 8237 Field-Replaceable Parts .............................................................. 4-18
A-1. Straight-Through UTP Cable (RJ-45 to RJ-45), T568-A ....................... A-1
A-2. Straight-Through UTP Cable (RJ-45 to RJ-45), T568-B ....................... A-1
A-3. Straight-Through STP Cable (RJ-45 to IBM Data Connector) .............. A-2
A-4. Crossover UTP Cable (RJ-45 to RJ-45), T568-A ................................. A-2
A-5. Crossover UTP Cable (RJ-45 to RJ-45), T568-B ................................. A-2
A-6. Crossover STP Cable (RJ-45 to IBM Data Connector) ........................ A-3
A-7. Null-Modem Cable Connection ............................................................. A-3
Tables
1-1 Maximum Segment Lengths for the Supported Ethernet Types ............ 1-9
1-2 Noise Emission Characteristics of the 8237 ........................................ 1-14
3-1 Status LED Explanations ..................................................................... 3-44
3-2 Port LED Explanations ......................................................................... 3-45
4-1 LED Symptom/Fix Table ........................................................................ 4-1
4-2 Field-Replaceable Parts List ................................................................ 4-17
4-3 Features That Can Be Purchased ....................................................... 4-19
4-4 8237 Power Cords by Country ............................................................. 4-19

Copyright IBM Corp. 1997 ix
Safety Information
Danger: Before you begin to install this product, read the safety information
in Caution: Safety Information— Read This First, SD21-0030. This booklet
describes safe procedures for cabling and plugging in electrical equipment.
Varning—livsfara: Innan du börjar installera den här produkten bör du läsa
säkerhetsinformationen i dokumentet
Varning: Säkerhetsföereskrifter—Läs detta
först
, SD21-0030. Där beskrivs hur du på ett säkert sätt ansluter elektrisk
utrustning.
Fare: Ffr du begynner å installere dette produktet, må du lese
sikkerhetsinformasjonen i
Advarsel:Sikkerhetsinformasjon—Les dette først , SD21-
0030 som beskriver sikkerhetsrutinene for kabling og tilkobling av elektrisk utstyr.
Fare! Ffr du installerer dette produkt, skal du laesesikkerhedsforskrifterne i
NB:
Sikkerhedsforskrifter—Laes dette først SD21-0030. Vejledningen beskriver
denfremgangsmåde, du skal bruge ved tilslutning af kabler og udstyr.
Gevaar: Voordat u begint met de installatie van dit produkt, moet u eerst de
veiligheidsinstructies lezen in de brochure PAS OP!
Veiligheidsinstructies—Lees dit
erst
, SD21-0030. Hierin wordt beschreven hoe u electrische apparatuur op een
veilige manier moet bekabelen en aansluiten.
Gevaar Voordat u begint met het installeren van dit produkt, dient u eerst de
veiligheidsrichtlijnen te lezen die zijn vermeld in de publikatie
Caution: Safety
Information - Read This First
, SD21-0030. In dit boekje vindt u veilige procedures
voor het aansluiten van elektrische appratuur.
Vorsicht: Bevor mit der Installation des Produktes begonnen wird, die
Sicherheitshinweise in
Achtung:Sicherheitsinformationen—Bitte zuerst lesen , IBM
Form SD21-0030. Diese Veröeffentlichung beschreibt die Sicherheitsvorkehrungen
für das Verkabeln und AnschlieBen elektrischer Geräte
Danger : Avant d’installer le présent produit, consultez le livret Attention:
Informations pour la
sécurité— Lisez-moi d’abord , SD21-0030, qui décrit les
procédures á respecter pour effectuer les opérations de cáblage et brancher les
équipements électriques en toute sécurité.

x8237 Hub Installation and Planning Guide
Danger: Avant de procéder á l’installation de ce produit, lisez d’abord les
consignes de sécurité dans la brochure
ATTENTION: Consignes de sécurité—A lire
au préalable
, SD21-0030. Cette brochure décrit les procédures pour cábler et
connecter les appareils électriques en toute sécurité.
Pericolo: prima di iniziare l’installazione di questo prodotto, leggere le
informazioni relative alla sicurezza riportate nell’opuscolo
Attenzione: Informazioni di
sicurezza—Prime informazioni da leggere
in cui sono descritte le procedure per il
cablaggio ed il collegamento di apparecchiature elettriche.
Perigo: Antes de iniciar a instalação deste produto, leia as informações de
segurança
Cuidado: Informações de Segurança—Leia Primeiro , SD21-0030. Este
documento descreve como efectuar, de um modo seguro, as ligações eléctricas dos
equipamentos.
Peligro: Antes de empezar a instalar este producto, lea la información de
seguridad en
Atención: Información de Seguridad—Lea Esto Primero , SD21-0030.
Este documento describe los procedimientos de seguridad para cablear y enchufar
equipos eléctricos.
Perigo: Antes de começar a instalar este produto, leia as informações de
segurança contidas em
Cuidado:Informações Sobre Segurança—Leia Isto Primeiro ,
SD21-0030. Esse folheto descreve procedimentos de segurança para a instalação
de cabos e conexões em equipamentos elétricos.
Vaara: Ennen kuin aloitat tämän tuotteen asennuksen, lue julkaisussa
Varoitus: Turvaohjeet—Lue tämä ensin , SD21-0030, olevat turvaohjeet. Tässä
kirjasessa on ohjeet siitä, miten sähkölaitteet kaapeloidaan ja kytketään turvallisesti.
Vigyázat: Mielôtt megkezdi a berendezés üezembe helyezését, olvassa el a
Caution: Safety Information— Read This First , SD21-0030 könyvecskében leírt
biztonsági információkat. Ez a könyv leírja, milyen biztonsági intézkedéseket kell
megtenni az elektromos berendezés huzalozasakor illetve csatlakoztatásakor.

Safety Information xi
Caution:
The ac power outlet must be located near the unit and easily accessible.
Waarschuwing:
Het stopcontact moet zich in de nabijheid van de eenheid bevinden en gemakkelijk
toegankelijk zijn.
Cuidado:
A tomada de corrente alternada deve estar próxima da unidade e ser facilmente
acessível.
Pas på!
Stikkontakten skal være placeret i nærheden af enheden og være let tilgængelig.
Waarschuwing:
Het stopcontact moet zich dichtbij de eenheid bevinden en goed toegankelijk zijn.

xii 8237 Hub Installation and Planning Guide
Varoitus:
Yksikkö on sijoitettava lähelle pistorasiaa siten, että sen luo on esteetön pääsy.
Attention
Le socle de prise de courant alternatif doit se trouver près de l'unité etêtre
facilement accessible.
Achtung:
Die Steckdose muss nahe beim Gerät und leicht zugänglich sein.
Attenzione:
La presa di alimentazione ca deve essere collocata accanto all'unità e deve essere
facilmente accessibile.
Advarsel:
Stikkontakten må være nær enheten og være lett tilgjengelig.
Cuidado:
A tomada eléctrica deve estar localizada perto da unidade e ser de fácil acesso.
Precaución:
La toma de alimentación CA debe colocarse cerca de la unidad y ser de fácil
acceso.
VARNING:
Eluttaget måste vara lättåtkomligt och placerat nära enheten.

Safety Information xiii
Lithium Battery
The IBM 8237 Stackable Ethernet Hub 10BASE-T contains a non-replaceable
lithium battery that, if disposed of improperly, can cause a fire, an explosion, or a
severe burn. At the end of the life of this machine, return the IBM 8237 Stackable
Ethernet Hub 10BASE-T to IBM or dispose of it according to local regulations.

xiv 8237 Hub Installation and Planning Guide

Copyright IBM Corp. 1997 xv
About This Manual
This manual describes the features of the IBM 8237 Stackable Ethernet Hub
10BASE-T (8237) and explains how to plan for 8237s in your new or existing
network, how to install 8237s, and how to administer 8237s.
Who Should Read This Manual
If you are a network planner, a hardware installer, a network administrator, or a
service engineer, this manual will help you in your work with 8237s.
How This Manual is Organized
This manual contains the following sections:
•Chapter 1, "Introduction and Planning"
Describes the features of the 8237 and provides information you will need to
integrate 8237s into your new or existing network.
•Chapter 2, "Installing the 8237"
Provides step-by-step instructions for installing the 8237 and its features.
•Chapter 3, "8237 Administration"
Helps you determine which administrative actions are available to your 8237
installation, and then gives instructions for performing the actions.
•Chapter 4, "Troubleshooting, Installation, and Replacement Procedures"
Gives the procedure for hot-swapping 8237s, provides step-by-step instructions
on installing all customer-replaceable parts, and lists the available replacement
parts. This chapter also gives steps for troubleshooting and for preparing to
make a call to IBM Service.
•Appendix A, "Cable Pinout Diagrams"
Provides pinout diagrams for the cables and connectors that the 8237 accepts.
•Appendix B, "The IBM 8237 Management Information Base"
Lists the IBM 8237 private MIB.
•Appendix C, "Product Warranty and Notices"
Provides emissions notices, a list of trademarks, and a statement of warranty.
•Glossary and Index
The Glossary gives definitions of the acronyms and key terms used in this
manual, and the Index helps you to find the information you are looking for.

xvi 8237 Hub Installation and Planning Guide
Technical and Planning References
You may find these publications helpful in planning your network or in answering
detailed technical questions.
•ISO/IEC 8802-3: 1996 ANSI/IEEE Std 802.3 1996 edition Information
Technology - Local and Metropolitan Area Networks - Part 3:
Carrier Sense
Multiple Access with Collision Detection (CSMA/CD) Access Method and
Physical Layer Specifications.
•IEEE Std. 802.3u-1995 (Supplement to ISO/IEC 8802-3: 1993). IEEE
Standards for Local and Metropolitan Area Networks: (Supplement to
Carrier
Sense Multiple Access with Collision Detection (CSMA/CD) Access Method and
Physical Layer Specifications
, ANSI/IEEE Standard 802.3, 1993 edition). Media
Access Control (MAC) Parameters, Physical Layer, Medium Attachment Units,
and Repeater for 100 Mb/s Operation, Type 100BASE-T (Clauses 21-30).
•
Commercial Building Telecommunications Cabling Standard , ANSI/TIA/EIA
Standard 568-A.
•
Commercial Building Standard for Telecommunications Pathways and Spaces ,
ANSI/EIA/TIA Standard 569.
•
Administration Standard for the Telecommunications Infrastructure of
Commercial Buildings
, ANSI/TIA/EIA Standard 606.
•
Grounding and Bonding Requirements for Telecommunications in Commercial
Buildings
, ANSI/TIA/EIA Standard 607.
•
Generic Cabling for Customer Premises Cabling , ISO/IEC International
Standard 11801.
If you intend to use STP cabling, refer to:
•
IBM Cabling System Planning and Installation Guide , GA27-3361.
If you intend to use optical fiber cabling, refer to:
•
IBM Cabling System Optical Fiber Planning and Installation Guide , GA27-3943.

Copyright IBM Corp. 1997 1-1
Chapter 1. Introduction and Planning
This chapter describes the features of the IBM 8237 Stackable Ethernet Hub
10BASE-T (8237) and provides information you will need to integrate 8237s into
your new or existing network.
The 8237 The 8237 is a stackable Ethernet hub that comes in three models:
•Model 001, which incorporates sixteen 10BASE-T Ethernet ports supporting the
IEEE 802.3 10BASE-T specification over category 3, 4, or 5,100-ohm UTP or
ScTP cabling or 150-ohm STP-A cabling. Each 8237 can accommodate an
optional Media Expansion Port, or Fast Expansion Module, providing
connectivity to AUI, 10BASE2, 10BASE-FL, 10BASE-T/100BASE-TX, or
100BASE-FX networks, offering maximum flexibility in system connectivity.
•Model 002, which provides all of the connectivity features of Model 001 and
includes an SNMP agent that permits management of one or more Model 001s.
•Model 003, which incorporates all of the connectivity and management features
of Model 002 plus a remote monitoring (RMON) agent.
Figure 1-1. Front View of the IBM 8237 Stackable Ethernet Hub 10BASE-T

1-2 8237 Hub Installation and Planning Guide
Features All 8237 models include these features:
•Sixteen 10BASE-T ports with shielded RJ-45 connectors that support the IEEE
802.3 10BASE-T specification.
•All of the 10BASE-T ports are Medium Dependent Interface-X (MDI-X) ports.
These ports perform an internal crossover function that allows easy connection
to other devices using standard cables.
•The sixteenth port is also accessible without the internal crossover function, at
the port marked "16-MDI," permitting connection to devices having an internal
crossover function using standard straight-through cables.
•A front-panel Expansion Port slot to accommodate an optional, slide-in Media
Expansion Port, or Fast Expansion Module, for connecting to AUI, 10BASE2,
10BASE-FL, FOIRL, 10BASE-T/100BASE-TX, or 100BASE-FX networks.
•Three independent 10-Mbps Ethernet backplanes.
•EtherWatch LED bars to display hub utilization and collision rates.
•Repeating of all Ethernet frame formats.
•Auto-partitioning and reconnecting of ports whose attached devices create
excessive collisions.
•Jabber protection by disabling a port that receives 65536 bits of continuous
transmission and re-enabling the port when the condition clears.
•A serial management port for configuring the 8237 and upgrading microcode via
Xmodem download.
•LEDs that indicate link status, activity, and partition status at the port level.
•Storage of vital configuration data in nonvolatile memory.
•Intrusion prevention: The 8237 can be configured to issue warnings or disable a
port automatically when frames are received at that port from any MAC address
other than the one authorized to send to that port.
•Eavesdropping protection: The 8237 can be configured so that a port will repeat
packets with scrambled data if the destination address does not match the Last
Source Address for that port.
•Can be mounted in an EIA standard 19-inch rack (mounting brackets included).
The 8237 can also be placed on a tabletop or shelf.
•Up to ten 8237s in any combination of models can be configured in a stack.
Model 002 provides these additional features to the entire stack:
•An SNMP agent that provides support for these Management Information
Bases (MIBs):
- RFC 1213 (MIB II)
- RFC 1516 (SNMP repeater MIB)
- RFC 1643 (Ethernet MIB)
- Novell Hub MIB
- IBM private MIB (listed in Appendix B).

Chapter 1 Introduction and Planning 1-3
•A serial management port for configuring the 8237, upgrading microcode via
TFTP, and out-of-band management.
•A user interface, accessible by means of VT100 terminal emulation (out-of-
band) or Telnet (in-band), for issuing management commands and retrieving
information and statistics concerning individual 8237s, backplanes, or the entire
stack.
•SNMP manageability over IP networks using the following frame formats:
Ethernet II
Ethernet SNAP.
•SNMP manageability over IPX** networks using the following frame formats:
Ethernet II
IEEE 802.3
IEEE 802.2
IEEE 802.2 SNAP.
•Manageability using optional applications and platforms, such as IBM Nways
Workgroup Manager for Windows NT, and Nways Campus Manager LAN for
AIX.
•For IP networks:
- SNMP manageability over a Serial Line Internet Protocol (SLIP) link to the
management port
- Support for BootP for configuring and upgrading the microcode of any 8237
Model 002 or Model 003
- Support for TFTP for upgrading the microcode of any Model 002 or
Model 003
- Telnet support.
•For IPX networks, Novell Hub Management Interface (HMI) compliance.
•Field upgrades: Model 002 can be upgraded to Model 003.
Model 003 provides these additional features:
•All connectivity features, plus all management features of Model 002. In
addition, Model 003 incorporates an RMON agent providing the functions
defined in RFC 1757.
•The Model 003 RMON agent can be managed by using optional applications
and platforms, such as Nways Workgroup Remote Monitor for Windows, Nways
Campus Manager Remote Monitor for AIX, Nways Campus Manager Remote
Monitor Advanced for AIX, Nways Campus Manager Remote Monitor for
HP-UX, and Nways Campus Manager Remote Monitor Advanced for HP-UX.