3com 3800 User Manual

® http://www.3com.com/ SuperStack ® II Switch 3800 User Guide Part No. DUA1691-0AAA01100004-00 Rev. 01Published April 1998 SW3800.BK Page i Tuesda

x 9 S TATUS M ONITORING AND S TATISTICS Status Monitoring 9-1Port Statistics 9-4Port Errors 9-6Switch Logging 9-7Local Logging

7-2 CHAPTER 7: SPANNING TREE PROTOCOL (STP)Figure 7-1 Network with an illegal topologyThis configuration is illegal because it creates loops that cau

Overview of the Spanning Tree Protocol 7-3If the link through Bridge C fails, as shown in Figure 7-3, the STP system reconfigures the network so that t

7-4 CHAPTER 7: SPANNING TREE PROTOCOL (STP)The Root Bridge generates BPDUs on all ports at a regular interval known as the Hello Time. All other bridg

Spanning Tree Domains 7-5 Within any given STPD, all VLANs belonging to it use the same spanning tree.Care must be taken to ensure that STPD instance

7-6 CHAPTER 7: SPANNING TREE PROTOCOL (STP)STP Configurations When you assign VLANs to an STPD, pay careful attention to the STP configuration and its e

STP Configurations 7-7When the Switches in this configuration start up, STP configures each STP domain such that there are no active loops in the topolo

7-8 CHAPTER 7: SPANNING TREE PROTOCOL (STP)STP Configurations to AvoidWithin a single STPD, you must be careful when configuring your VLANs. The followi

Creating STP Domains 7-9Figure 7-6 shows a similar configuration in which the VLANs are all port-based. The trunk connections between the Switches requ

7-10 CHAPTER 7: SPANNING TREE PROTOCOL (STP)Enabling STP on the SwitchTo enable STP for one or more STP domains on your Switch, use the following comm

Configuring STP 7-11config stpd <stpd_name> delete vlan [<name> | all]Allows you to remove one or all VLANs from an STPD. If all is specif

xi Fiber Optic Ports A-3Lithium Battery A-4L’information de Sécurité Importante A-4Power A-5Cordon électrique A-6Fuse A-6Port

7-12 CHAPTER 7: SPANNING TREE PROTOCOL (STP)ConfigurationExampleThe following example creates and enables an STPD named Backbone_st. It assigns the Man

Displaying STP Settings 7-13Sample output from the command is as follows:3C16910:28 # sh stpd s0 po 5-8Stpd: s0 Port: 8 PortId: 8008 Stp: ENABLED Pat

7-14 CHAPTER 7: SPANNING TREE PROTOCOL (STP)Disabling and Resetting STPTo disable STP or return STP settings to their defaults, use the commands liste

8IP UNICAST ROUTINGThis chapter describes how to configure IP routing on the Switch 3800. It assumes that you are already familiar with IP unicast rout

8-2 CHAPTER 8: IP UNICAST ROUTINGIn Figure 8-1, a Switch 3800 is shown with two VLANs defined: Finance and Personnel. Ports 1 and 3 are assigned to Fin

Overview of IP Unicast Routing 8-3Dynamic RoutesDynamic routes are typically learned by way of RIP. Routers using RIP exchange information in their ro

8-4 CHAPTER 8: IP UNICAST ROUTINGConfiguring IP Unicast RoutingThis section describes the commands associated with configuring IP unicast routing on the

Verifying the IP Unicast Routing Configuration 8-5Verifying the IP Unicast Routing ConfigurationUse the “show iproute” command to display the current c

8-6 CHAPTER 8: IP UNICAST ROUTINGTable 8-1 describes the commands used to configure basic IP settings on the Switch.Table 8-1 Basic IP Commands Comma

Configuring DHCP/BOOTP Relay 8-7Table 8-2 describes the commands used to configure the IP route table.Table 8-3 describes the commands used to configure

xii G LOSSARY I NDEX 3C OM C ORPORATION L IMITED W ARRANTY SW3800.BK Page xii Tuesday, May 5, 1998 5:20 PM

8-8 CHAPTER 8: IP UNICAST ROUTINGenable rip splithorizon Enables the split horizon algorithm for RIP. Default setting is enabled.enable rip triggerupd

Configuring DHCP/BOOTP Relay 8-9Table 8-4 describes the commands used to configure the ICMP protocol.disable rip splithorizon Disables split horizon.di

8-10 CHAPTER 8: IP UNICAST ROUTINGRouting Configuration ExampleFigure 8-2 illustrates a Switch that has three VLANs defined as follows: Finance Protoc

Routing Configuration Example 8-11Figure 8-2 Unicast Routing Configuration ExampleIn this configuration, all IP traffic from stations connected to port

8-12 CHAPTER 8: IP UNICAST ROUTINGDisplaying Router SettingsTo display settings for various IP routing components, use the commands listed in Table 8-

Resetting and Disabling Router Settings 8-13Resetting and Disabling Router SettingsTo return router settings to their defaults and disable routing fun

8-14 CHAPTER 8: IP UNICAST ROUTINGdisable rip {vlan <name> | all} Disables RIP for one or more VLANs. When RIP is disabled, the parameters are n

9STATUS MONITORING AND STATISTICSThis chapter describes how to view the current operating status of the Switch, how to display information in the Swit

9-2 CHAPTER 9: STATUS MONITORING AND STATISTICSshow ip config {vlan <name> | all} Displays configuration information for one or more VLANs, incl

Status Monitoring 9-3show port <portlist> collisions Displays collision statistics for each port.show port <portlist> config Displays sta

A BOUT T HIS G UIDEAbout This Guide provides an overview of this guide, describes guide conventions, tells you where to look for specific informatio

9-4 CHAPTER 9: STATUS MONITORING AND STATISTICSPort Statistics The Switch 3800 provides a facility for viewing port statistic information. The summary

Port Statistics 9-5The following port statistic information is collected by the Switch:Link Status — The current status of the link. Options are: Rea

9-6 CHAPTER 9: STATUS MONITORING AND STATISTICSPort Errors The Switch 3800 keeps track of errors for each port.To view port error, typeshow port <p

Switch Logging 9-7Receive Jabber Frames (RX Jab) — The total number of frames received by the port that were of longer than the support maximum length

9-8 CHAPTER 9: STATUS MONITORING AND STATISTICS Message — The message contains the log information with text that is specific to the problem.Local Log

Switch Logging 9-9If priority is not specified, only messages of critical priority are displayed. If the subsystem is not specified, all subsystems are

9-10 CHAPTER 9: STATUS MONITORING AND STATISTICSLogging Commands The commands described in Table 9-4 allow you to do the following: Configure logging

RMON 9-11RMON Using the Remote Monitoring (RMON) capabilities of the Switch allows network administrators to make decisions about improving Switch effi

9-12 CHAPTER 9: STATUS MONITORING AND STATISTICSA typical RMON setup consists of the following two components: The RMON probe — An intelligent, remot

RMON 9-13AlarmsThe Alarms group provides a versatile, general mechanism for setting threshold and sampling intervals to generate events on any MIB var

2 ABOUT THIS GUIDEFinding Information in This GuideThis table shows where to find specific information in this guide.Task LocationLearning concepts Chap

9-14 CHAPTER 9: STATUS MONITORING AND STATISTICSAn RMON probe, however, autonomously looks at the network on behalf of the management workstation with

RMON 9-15When using the RMON features of the Switch, you should note the following: After the default sessions are created, they have no special stat

9-16 CHAPTER 9: STATUS MONITORING AND STATISTICSSW3800.BK Page 16 Tuesday, May 5, 1998 5:20 PM

10SOFTWARE UPGRADE AND BOOT OPTIONSThis chapter describes the procedure for upgrading the Switch software image. It also covers how to save and load a

10-2 CHAPTER 10: SOFTWARE UPGRADE AND BOOT OPTIONSYou can select which image the Switch will load on the next reboot by using the following command:us

Boot Option Commands 10-3Returning to FactoryDefaultsTo return the Switch configuration to factory defaults, use the following command:unconfig switchT

10-4 CHAPTER 10: SOFTWARE UPGRADE AND BOOT OPTIONSSW3800.BK Page 4 Tuesday, May 5, 1998 5:20 PM

ASAFETY INFORMATIONYou must read the following safety information before carrying out any installation or removal of components, or any maintenance pr

A-2 APPENDIX A: SAFETY INFORMATION This unit operates under SELV (Safety Extra Low Voltage) conditions according to IEC 950. The conditions are only

Important Safety Information A-3 If the power cord plug is unsuitable and must be replaced, you may find other codings for the respective connections.

Conventions 3Conventions Table 1 and Table 2 list conventions that are used throughout this guide.Table 1 Notice IconsIcon Notice Type Alerts you to

A-4 APPENDIX A: SAFETY INFORMATIONLithium Battery Replace the lithium battery with the same or equivalent type, as recommended by the manufacturer.W

L’information de Sécurité Importante A-5 Pour réduire les risques d'incendie ou de choc électrique, installez ce groupe sous abri dans une zone

A-6 APPENDIX A: SAFETY INFORMATIONCordon électrique Il doit être agréé dans le pays d'utilisation : Si la prise mâle du cordon électrique est

L’information de Sécurité Importante A-7porte-fusibles. Pour ce groupe, vous devez uniquement utiliser des fusibles réalisés par le même constructeur

A-8 APPENDIX A: SAFETY INFORMATION les batteries au lithium ne figurent pas sur la liste EPA des déchets dangereux. Par conséquent, vous pouvez en gén

Wichtige Sicherheitsinformationen A-9 Das Gerät muß an eine geerdete Steckdose angeschlossen werden, die die europäischen Sicherheitsnormen erfüllt.

A-10 APPENDIX A: SAFETY INFORMATION Zur Erfüllung europäischer Sicherheitsnormen darf keine Ersatzsicherung am Geräteeingang angebracht werden. Es dü

Wichtige Sicherheitsinformationen A-11Lithiumbatterie Die Lithiumbatterie nach den Empfehlungen des Herstellers durch eine Batterie des gleichen ode

A-12 APPENDIX A: SAFETY INFORMATIONSW3800.BK Page 12 Tuesday, May 5, 1998 5:20 PM

BTECHNICAL SPECIFICATIONSPhysical Dimensions Height: 3.5 inches x Width: 17.32 inches x Depth: 17.32 inches Weight: 22 poundsEnvironmental Requiremen

4 ABOUT THIS GUIDECommand Syntax SymbolsYou may see a variety of symbols shown as part of the command syntax. These symbols explain how to enter the c

B-2 APPENDIX B: TECHNICAL SPECIFICATIONSStandards Supported EthernetISO 8802-3IEEE 802.3z/D3ISO 10038:1993 (IEEE 802.1D)IEEE 802.1Q/D10SNMPSNMP protoc

CTROUBLESHOOTINGIf you encounter problems when using the Switch, this Appendix may be helpful. If you have a problem which is not listed here or in th

C-2 APPENDIX C: TROUBLESHOOTINGBoth sides of the link must have the same setting for autonegotiation. It the two are different, typically the side wit

Using the Command-Line Interface C-3Traps are not received by the SNMP Network Manager:Check that the SNMP Network Manager's IP address and commu

C-4 APPENDIX C: TROUBLESHOOTINGYou forget your password and cannot log on:If you are not an administrator, another user having administrator access le

Using the Command-Line Interface C-5VLAN Names:There are restrictions on VLAN names. They cannot contain white spaces and cannot start with a numeric

C-6 APPENDIX C: TROUBLESHOOTINGThe Switch keeps aging out endstation entries in the Switch Forwarding Database (FDB): Reduce the number of topology ch

DTECHNICAL SUPPORT3Com provides easy access to technical support information through a variety of services. This appendix describes these services.Inf

D-2 APPENDIX D: TECHNICAL SUPPORTAccess by Digital ModemISDN users can dial in to 3ComBBS using a digital modem for fast access up to 56 Kbps. To acce

Support from Your Network Supplier D-33ComForum onCompuServe®Online Service3ComForum is a CompuServe-based service containing patches, software, drive

Line-Editing Commands 5Line-Editing CommandsTable 4 describes the line-editing commands available using the command-line interface.The command syntax

D-4 APPENDIX D: TECHNICAL SUPPORTSupport from 3Com If you are unable to receive support from your network supplier, technical support contracts are av

Returning Products for Repair D-5Returning Products for RepairBefore you send a product directly to 3Com for repair, you must first be obtain a Return

D-6 APPENDIX D: TECHNICAL SUPPORTSW3800.BK Page 6 Tuesday, May 5, 1998 5:20 PM

GLOSSARYageing The automatic removal of dynamic entries from the Switch Database that have timed-out and are no longer valid.ARP Address Resolution Pr

2 GLOSSARYCSMA/CD Carrier Sense Multiple Access/Collision Detection that is a channel access method used by Ethernet and IEEE 802.3 standards in which

3LAN Local Area Network that consists of connected computing resources (such as PCs, printers, and servers) covering a relatively small geographic are

4 GLOSSARYon a wide range of computers and networking equipment and may be used to manage many aspects of network and endstation operation.Spanning Tr

INDEX 1INDEXNumerics3Com Bulletin Board Service (3ComBBS) D-13Com sales offices D-43Com URL D-13ComFacts D-23ComForum D-3Aaccounts, creating

2 INDEXrouter interfaces 8-1router show commands (table) 8-12routing tableconfiguration commands (table) 8-7dynamic routes 8-3populating 8-2s

INDEX 3forward delay 4-14, 7-11Hello Timeconfiguring 4-14, 7-11description 7-4Max Ageconfiguring 4-14, 7-11overview 7-1path costs 4-15, 7-11

6 ABOUT THIS GUIDESW3800.BK Page 6 Tuesday, May 5, 1998 5:20 PM

4 INDEXSW3800.BK Page 4 Tuesday, May 5, 1998 5:20 PM

3Com Corporation LIMITED WARRANTYHARDWARE 3Com warrants its hardware products to be free from defects in workmanship and materials, under normal use a

3COM SHALL NOT BE LIABLE UNDER THIS WARRANTY IF ITS TESTING AND EXAMINATION DISCLOSE THAT THE ALLEGED DEFECT IN THE PRODUCT DOES NOT EXIST OR WAS CAUS

1SWITCH 3800 OVERVIEWThis chapter describes the following: Switch 3800 features How to use the Switch 3800 in your network configuration Switch 3800

ii 3Com Corporation5400 Bayfront Plaza Santa Clara, California 95052-8145 Copyright © 3Com Corporation, 1998. All rights reserved. No part of this

1-2 CHAPTER 1: SWITCH 3800 OVERVIEW Virtual LANs (VLANs) Support for 64 VLANs on a single Switch 3800 Support for IEEE 802.1Q tagging Controls tra

Summary of Features 1-3Port Connections The Switch 3800 has 24 autosensing 10BASE-T/100BASE-TX ports with standard RJ-45 connectors, and supports one

1-4 CHAPTER 1: SWITCH 3800 OVERVIEWIn the event that the active main port fails or loses link status, the standby port is automatically activated. Whe

Network Configuration Example 1-5Priority Access Control Enabled (PACE)The Switch recognizes the PACE bit set by 3Com Etherlink® adapters and other de

1-6 CHAPTER 1: SWITCH 3800 OVERVIEWFigure 1-2 Switch 3800 used in a backbone configurationThe Switch 1100 on each floor has a 100Mbps full-duplex link

Switch 3800 Front View 1-7In addition to providing a fast backbone between Ethernet LANs, Gigabit Ethernet equipped file servers and services may be di

1-8 CHAPTER 1: SWITCH 3800 OVERVIEWFor more information on 1000BASE-SX and 1000BASE-LX characteristics refer to IEEE Draft P802.3z/D4.2 Tables 38-2 an

Switch 3800 Rear View 1-9Switch 3800 Rear ViewFigure 1-4 shows the Switch 3800 rear view.Figure 1-4 Switch 3800 rear viewThe rear panel has the foll

1-10 CHAPTER 1: SWITCH 3800 OVERVIEWMAC AddressThis label shows the unique Ethernet MAC address assigned to this device.Console PortThe console port (

2INSTALLATION AND SETUPThis chapter describes the following: How to decide where to install the Switch 3800 Ethernet configuration rules How to inst

iii VCCI Statement Information To The User If this equipment does cause interference to radio or television reception, which can be determined by tur

2-2 CHAPTER 2: INSTALLATION AND SETUP Water or moisture cannot enter the case of the unit. Temperature must be within the range of 0 to 40 degrees C

Installing the Switch 3800 2-3Figure 2-1 Fitting the mounting bracket5 Repeat the three previous steps for the other side of the Switch.6 Refer to t

2-4 CHAPTER 2: INSTALLATION AND SETUPStacking the Switchand Other DevicesUp to four units can be placed on top of one another. If mixing Switch 3800,

Connecting Equipment to the Console Port 2-5Figure 2-2 shows the pin-outs for a 9-pin to RS-232 25-pin null modem cable.Figure 2-2 Null modem cable

2-6 CHAPTER 2: INSTALLATION AND SETUPPowering-up the SwitchTo power-up the Switch, follow these steps:1 Connect the power cable to the Switch.2 Connec

Logging on for the First Time 2-75 Assign an IP address and subnetwork mask for VLAN default. The example below assigns an IP address of 123.45.67.8 a

2-8 CHAPTER 2: INSTALLATION AND SETUPSW3800.BK Page 8 Tuesday, May 5, 1998 5:20 PM

3ACCESSING THE SWITCHThis chapter describes the following information that you can use to begin managing the Switch 3800: Security access level overv

3-2 CHAPTER 3: ACCESSING THE SWITCHAdministrator AccessLevelAn administrator-level account can view and change all Switch parameters, add and delete u

Security Access Levels 3-34 Enter the new password at the prompt.5 Re-enter the new password at the prompt.6 Save your changes by typingsaveCreating a

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3-4 CHAPTER 3: ACCESSING THE SWITCH3 Enter the new password at the prompt.4 Re-enter the new password at the prompt.5 Save your changes by typingsaveI

Using Telnet 3-5Using the ConsoleInterfaceThe command-line interface built into the Switch is accessible by way of the 9-pin, RS-232 console port loca

3-6 CHAPTER 3: ACCESSING THE SWITCHYou can enable BOOTP on a per-VLAN basis by using the following command:enable bootp vlan [<name> | all]Manua

Using Telnet 3-74 At the password prompt, enter the password and press [Return].When you have successfully logged on to the Switch, the command-line p

3-8 CHAPTER 3: ACCESSING THE SWITCHSample output from the show session command is as follows:3C16910:2 # sh sess# Login Time User Type Location=======

Using SNMP 3-9Accessing SwitchAgentsIn order to have access to the SNMP agent residing in the Switch, at least one VLAN on the Switch must have an IP

3-10 CHAPTER 3: ACCESSING THE SWITCHConfiguring SNMPSettingsThe following SNMP parameters can be configured on the Switch: Authorized trap receivers —

Using SNMP 3-11Table 3-4 describes SNMP configuration commands.Table 3-4 SNMP Configuration Commands Command Descriptionconfig vlan <name> ipadd

3-12 CHAPTER 3: ACCESSING THE SWITCHDisplaying SNMPSettingsTo display the SNMP settings configured on the Switch 3800, use the following command:show m

Configuring Ports 3-13Options for the ping command are described in Table 3-6.Traceroute The traceroute command allows you to trace the routed path be

v C ONTENTS A BOUT T HIS G UIDE Introduction 1Terminology 1Finding Information in This Guide 2Conventions 3Command Syntax Symbols

3-14 CHAPTER 3: ACCESSING THE SWITCHConfiguringAutonegotiationBy default, the Switch 3800 is configured to use autonegotiation for all ports. Autonegoti

Load Sharing 3-15Load Sharing Load sharing with the Switch 3800 allows you to increase bandwidth and resilience by using a group of ports to carry tra

3-16 CHAPTER 3: ACCESSING THE SWITCHWhen you define a load-sharing group, you assign a group of ports to a single, logical port number. To enable or di

SmartRedundancy 3-17SmartRedundancy SmartRedundancy for the Switch 3800 refers to fail-over behavior of the main and standby Gigabit Ethernet ports. S

3-18 CHAPTER 3: ACCESSING THE SWITCHdisable smartredundancy <portlist> Allows you to disable the SmartRedundancy feature. If the feature is disa

4COMMANDSThis chapter contains a description of each command-line interface command for the Switch 3800. It also provides the following information re

4-2 CHAPTER 4: COMMANDSIf the command does not include a parameter, skip to Step 3. If the command requires more information, or if you want to includ

Understanding the Command Syntax 4-3config vlan engineering add port 1-3,6could use the following shortcut:config engineering add port 1-3, 6Numerical

4-4 CHAPTER 4: COMMANDSLine-Editing CommandsTable 4-2 describes the line-editing commands available using the command-line interface.vertical bar | Se

Command History Substitution 4-5Command History SubstitutionThe Switch 3800 “remembers” the last 50 commands you enter. You can display a list of thes

vi 2 I NSTALLATION AND S ETUP Following Safety Information 2-1Determining the Switch 3800 Location 2-1Configuration Rules for Ethernet

4-6 CHAPTER 4: COMMANDSSwitch 3800 CommandsThe tables in this section list all of the commands used on the Switch 3800. The commands are organized by

Switch 3800 Commands 4-7General SwitchCommandsTable 4-4 describes general Switch commands.Table 4-4 General Switch Commands Command Descriptionshow

4-8 CHAPTER 4: COMMANDSUser AccountCommandsTable 4-5 describes user account commands.config devicemode [bridging | iprouting] Allows you to configure

Switch 3800 Commands 4-9Switch ManagementCommandsTable 4-6 describes Switch management commandsTable 4-6 Switch Management Commands Command Descript

4-10 CHAPTER 4: COMMANDSVLAN Commands Table 4-7 describes VLAN commands.config snmp syscontact <string> Allows you to configure the name of the

Switch 3800 Commands 4-11Protocol Commands Table 4-8 describes protocol commands.FDB Commands Table 4-9 describes FDB commands.Table 4-8 Protocol Co

4-12 CHAPTER 4: COMMANDSPort Commands Table 4-10 describes port commands.create fdbentry <mac_address> vlan <name> <portlist>Allows

Switch 3800 Commands 4-13PACE Commands Table 4-11 describes PACE commands.config port <portlist> auto off {speed [10 | 100]} duplex [half | full

4-14 CHAPTER 4: COMMANDSSTP Commands Table 4-12 describes STP commands.Table 4-12 STP Commands Command Descriptionshow stpd {<stpd_name> | all

Switch 3800 Commands 4-15config stpd <stpd_name> port cost <value> <portlist>Allows you to specify the path cost of the port in this

vii Configuring SNMP Settings 3-10Displaying SNMP Settings 3-12Resetting and Disabling SNMP 3-12Checking Basic Connectivity 3-12Ping

4-16 CHAPTER 4: COMMANDSBasic IP Commands Table 4-13 describes basic IP commands.Table 4-13 Basic IP Commands Command Descriptionshow ipconfig {vlan

Switch 3800 Commands 4-17IP ARP Commands Table 4-14 describes IP ARP commands.disable bootp vlan [<name> | all] Allows you to disable the genera

4-18 CHAPTER 4: COMMANDSIP Route TableCommandsTable 4-15 describes IP route table commands.ICMP Commands Table 4-16 describes the commands used to con

Switch 3800 Commands 4-19enable icmp useredirects Allows you to enable the modification of route table information when an ICMP redirect message is re

4-20 CHAPTER 4: COMMANDSRIP Commands Table 4-17 describes the commands used to configure the RIP protocol.Table 4-17 RIP Commands Command Description

Switch 3800 Commands 4-21enable rip exportstatic Allows you to enable the advertisement of static routes using RIP. The default setting is enabled.dis

4-22 CHAPTER 4: COMMANDSLogging Commands Table 4-18 describes Switch logging commands.Table 4-18 Logging Commands Command Descriptionshow log config

Switch 3800 Commands 4-23Configuration andImage CommandsTable 4-19 describes configuration and image commands.config syslog <ipaddress> <facili

4-24 CHAPTER 4: COMMANDSdownload image <ipaddress> <filename> {primary | secondary}Allows you to download a new image from a TFTP server.

5VIRTUAL LANS (VLANS)Setting up Virtual Local Area Networks (VLANs) on the Switch 3800 eases many time-consuming tasks of network administration while

viii Port Commands 4-12PACE Commands 4-13STP Commands 4-14Basic IP Commands 4-16IP ARP Commands 4-17IP Route Table Commands 4

5-2 CHAPTER 5: VIRTUAL LANS (VLANS) It helps to control traffic.With traditional networks, congestion can be caused by broadcast traffic that is direct

Overview of Virtual LANs 5-3For example, in Figure 5-1, the VLANs are configured as followings: Ports 3, 6, and 17 are part of VLAN Marketing Ports 1

5-4 CHAPTER 5: VIRTUAL LANS (VLANS)Expanding Port-Based VLANs Across SwitchesTo create a port-based VLAN that spans two Switches you must do two thing

Overview of Virtual LANs 5-5Figure 5-3 illustrates two VLANs spanning two Switches. On Switch 1, ports 1–16 are part of VLAN Accounting; ports 17–24 a

5-6 CHAPTER 5: VIRTUAL LANS (VLANS)Tagged VLANsThe Switch 3800 uses the IEEE 802.1Q D4 draft standard for rules associated with VLAN tagging.Tagging i

Overview of Virtual LANs 5-7Figure 5-4 illustrates the physical view of a network that uses tagged and untagged traffic. Figure 5-4 Physical diagram

5-8 CHAPTER 5: VIRTUAL LANS (VLANS)In Figure 5-4 and Figure 5-5: The trunk port on each Switch carries traffic for both VLAN Marketing and VLAN Sales.

Overview of Virtual LANs 5-9The IP traffic has been divided into two IP subnets, 192.207.35.0 and 192.207.36.0. The subnets are internally routed by th

5-10 CHAPTER 5: VIRTUAL LANS (VLANS)Defining Protocol FiltersIf necessary, you can define a customized protocol filter based on EtherType, LLC, and/or SN

Configuring VLANs on the Switch 3800 5-11The Default VLANThe Switch 3800 ships with one default VLAN that has the following properties: The VLAN name

ix Configuring FDB Entries 6-3FDB Configuration Example 6-3Displaying FDB Entries 6-3Removing FDB Entries 6-4 7 S PANNING T REE P ROT

5-12 CHAPTER 5: VIRTUAL LANS (VLANS)Table 5-1 describes the commands used to configure a VLAN.VLAN ConfigurationExamplesThe following example creates a

Displaying VLAN Settings 5-13The following example creates a tag-based VLAN named video. It assigns the VLANid 1000. Ports 4–8 are added as tagged por

5-14 CHAPTER 5: VIRTUAL LANS (VLANS) Status for each port Enabled/disabled Tagged/untagged Protocol information IP address STPD informationSampl

Deleting and Resetting VLANs 5-15Sample output from this command is as follows:show protocol allProtocol Name Type Value-----------------

5-16 CHAPTER 5: VIRTUAL LANS (VLANS)SW3800.BK Page 16 Tuesday, May 5, 1998 5:20 PM

6SWITCH FORWARDING DATABASE (FDB)This chapter describes the contents of the Switch forwarding database (FDB), how the FDB works, and how to configure t

6-2 CHAPTER 6: SWITCH FORWARDING DATABASE (FDB) Permanent entries — Permanent entries are retained in the database if the Switch is reset or a power

Configuring FDB Entries 6-3Configuring FDB EntriesTo configure entries in the FDB, use the commands listed in Table 6-1.FDB ConfigurationExampleThis exam

6-4 CHAPTER 6: SWITCH FORWARDING DATABASE (FDB) portlist — displays the entries for one or more ports permanent — displays all permanent entriesThe

7SPANNING TREE PROTOCOL (STP)Using the Spanning Tree Protocol (STP) functionality of the Switch 3800 makes your network more fault tolerant.The follow