3Com 3C16476CS Service Manual

Baseline Switch 2250 Plus

User Guide

Bedienungsanleitung

3C16476CS

http://www.3com.com/

Part No. 10015237 Rev. BA Published February 2008

3Com Corporation • 350 Campus Drive • Marlborough • MA USA 01752-3064

Copyright © 2006, 3Com Corporation. All rights reserved. No part of this documentation may be reproduced in any form or by any means or used to make any derivative work (such as translation, transformation, or adaptation) without written permission from 3Com Corporation.

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CONTENTS

ABOUT THIS GUIDE

Conventions 5 Related Documentation 6 Documentation Comments 6

1 INTRODUCING THE BASELINE SWITCH

Overview of the Baseline Switch 2250 Plus 7 Features and Capabilities 7

Autosensing of MDI/MDIX Connections 7 Autonegotiating 10/100 Mbps Ports 7 SFP Ports 8 Traffic Prioritization 8 Forwarding of BPDU Packets 8

Physical Features 9

Front Panel 9 Rear Panel 12

Package Contents 12

2 INSTALLING THE SWITCH

Before You Begin 13 Positioning the Switch 13 Aufstellen des Switch 14 Rack-Mounting or Free-Standing 14

Using the Mounting Kit 14 Montagesatz Anweisungen 15 Placing Units On Top of Each Other 16

Supplying Power to the Switch 16

Checking for Correct Operation 16 Connecting a Network Device 17 Using SFP Transceivers 18

Approved SFP Transceivers 18

Inserting an SFP Transceiver 18

Removing an SFP Transceiver 19 Performing Spot Checks 19

3 CONNECTING TO THE WEB INTERFACE

Requirements for Accessing the Web Interface 21 Running the Discovery Application 21 Logging On to the Web Interface 23 Navigating the Web Interface 23

Menu 23

Buttons 25 Accessing the Interface Without Using Discovery 26

DHCP Assigned IP Address 26

Manually Assigned (Static) IP Address 26

4 CONFIGURING THE SWITCH

Configuration Overview 27 Device Summary Information 27 Administration Settings 29

Modifying the IP Address Settings 29

Automatic IP Configuration 29

IP Setup 30

Backup Configuration 30 Restore Configuration 30 Firmware Upgrade 31 Initialize 31 Reboot 32 System Access 32 System Time 34 SNMP 34

Configuring VLANs 36

VLAN 36 Forwarding Tagged/Untagged Frames 40 Sample VLAN Configurations 40 Spanning Tree 42 IGMP Snooping 43 IGMP Query 43 Broadcast Storm 44

Configuring Port Settings 44

Administration 44 Speed/Duplex for 1000 Mbps Connections 46 Link Aggregation 46 Spanning Tree per Port 48 Port Mirroring 50

Statistics 51 QoS VoIP Traffic Settings 52 Security 54

RADIUS Client 54

802.1X Settings 55

Monitoring 58

Address Table 58

Cable Diagnostics 58

Forgotten Password 61 Forgotten Static IP Address 62 Solving LED Issues 62 If the Problem Persists 63

A OBTAINING SUPPORT FOR YOUR PRODUCT

Register Your Product 65 Purchase Value-Added Services 65 Troubleshoot Online 65 Access Software Downloads 65 Telephone Technical Support and Repair 66 Contact Us 66

B SAFETY INFORMATION

Important Safety Information 69

C TECHNICAL INFORMATION

Related Standards 71

Environmental 71 Physical 71 Electrical 71

GLOSSARY

INDEX

REGULATORY NOTICES

5 TROUBLESHOOTING

Resetting to Factory Defaults 61

ABOUT THIS GUIDE

This guide describes how to install your Switch and perform initial management configurations.

This guide is intended for use by network administators who are responsible for installing and setting up network equipment. Consequently, it assumes a basic working knowledge of LANs (local area networks).

Diese Anleitung ist für die Benutzung durch Netzwerkadministratoren vorgesehen, die für die Installation und das einstellen von Netzwerkkomponenten verantwortlich sind; sie setzt Erfahrung bei der Arbeit mit LANs (Local Area Networks) voraus.

If release notes are shipped with your product and the information there differs from the information in this guide, follow the instructions in the release notes.

Most user guides and release notes are available in Adobe Acrobat Reader Portable Document Format (PDF) on the 3Com World Wide Web site:

http://www.3com.com

Conventions

Ta bl e 1 and Tab le 2 list conventions that are used

throughout this guide.

Ta b l e 1 Notice Icons

Icon Notice Type Description

Information note

Caution Information that alerts you to potential loss of

Warning Information that alerts you to potential

Ta b l e 2 Text Conventions

Convention Description

Screen displays

The words “enter” and “type”

Words in italics Italics are used to:

Information that describes important features or instructions

data or potential damage to an application, system, or device

personal injury

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 Return or Enter. Do not press Return or Enter when an instruction simply says “type.”

■ Emphasize a point.

■ Denote a new term at the place where it is

defined in the text.

■ Identify menu names, menu commands, and

software button names. Examples: From the Help menu, select Contents. Click OK.

6 ABOUT THIS GUIDE

Documentation Comments

Your suggestions are very important to us. They will help make our documentation more useful to you. Please e-mail comments about this document to 3Com at:

pddtechpubs_comments@3com.com

Please include the following information when contacting us:

■ Document title

Please note that we can only respond to comments and questions about 3Com product documentation at this e-mail address. Questions related to technical support or sales should be directed in the first instance to your network supplier.

■ Document part number (on the title page)

■ Page number (if appropriate)

Example:

■ 3Com Baseline Switch 2250 Plus User Guide

■ Part number: 10015237

■ Page 25

INTRODUCING THE BASELINE SWITCH

This chapter provides an overview of the features and capabilities of the 3Com It also identifies the contents of the Switch package and helps you get to know the physical features of the device.

Baseline Switch 2250 Plus.

Overview of the Baseline Switch 2250 Plus

The 3Com® Baseline Switch 2250 Plus is a versatile, easy-to-use unmanaged switch. It is ideal for users who want the high-speed performance of 10/100 switching with the added functionality of Gigabit links but do not need sophisticated management capabilities.

The Switch is shipped ready for use. No configuration is necessary, unless you want to configure advanced features such as VLAN support and link aggregation.

Features and Capabilities

The Switch has 48 shielded RJ-45, 10/100 Mbps auto-negotiating ports and two 10/100/1000BASE-T ports that operate in conjunction with two Small Form Factor Pluggable (SFP) transceiver slots on the front panel. Use these SFP transceiver slots for easy, flexible connection to fiber-based Gigabit media.

While there are four physical Gigabit ports, only a maximum of two can be operational at any given time.

Autosensing of MDI/MDIX Connections

All ports on the Switch can autosense both medium dependent interface (MDI) and medium dependent interface crossover (MDIX) connections. This allows you to connect network devices to each port using either a normal straight-through TP (twisted pair) cable or a ‘crossover’ TP cable.

Any port can therefore be used to connect to another switch port, server, or workstation without additional configuration.

Autonegotiating 10/100 Mbps Ports

Each 10/100 Mbps port automatically determines the speed and duplex mode of the connected equipment and provides a suitable switched connection. The 1000BASE-T ports also support automatic 10/100/1000 Mbps speed detection.

The 10/100 Mbps connections on these 1000BASE-T ports can operate in either half-duplex or full-duplex mode. 1000 Mbps connections, on the other hand, only operate in full duplex mode.

8 CHAPTER 1: INTRODUCING THE BASELINE SWITCH

SFP Ports

The two SFP ports support fiber Gigabit Ethernet short-wave (SX) and long-wave (LX) SFP transceivers in any combination. This offers you the flexibility of using SFP transceivers to provide connectivity between the Switch and a 1000 Mbps core network.

When an SFP port is in operation, the corresponding 10/100/1000BASE-T port is disabled.

Traffic Prioritization

The Switch offers priority queuing, which means all packets that are received are examined to see if they have been priority encoded. If a packet has been priority encoded, then the Switch will read the priority level and determine whether the packet should be directed through the normal or high priority channel. This feature is useful during excessive loads when one type of traffic may require priority over another. The Switch is configured to comply with 802.1p, VLAN tagged frames.

Traffic prioritization ensures that high priority data is forwarded through the Switch without being delayed by lower priority data. It differentiates traffic into classes and prioritizes those classes automatically. Traffic prioritization uses the multiple traffic queues that are present in the hardware of the Switch to ensure that high priority traffic is forwarded on a different queue from lower priority traffic, and is given preference over that traffic. This ensures that time-sensitive traffic gets the highest level of service. The 802.1D standard specifies eight distinct levels of priority (0 to 7), each of which relates to a particular

type of traffic. The priority levels and their traffic types are shown in the following table.

Ta b l e 3 Priority Levels for Traffic Types

Priority Level Traffic Type

0 Best effort

1 Background

2 Standard (spare)

3 Excellent effort (business critical)

4 Controlled load (streaming multimedia)

5 Video (interactive media), less than 100

milliseconds latency and jitter

6 Voice (interactive voice), less than 10

milliseconds latency and jitter.

7 Network control reserved traffic

Forwarding of BPDU Packets

Within an extended local area network that implements a spanning tree protocol topology, switches communicate with each other using bridge protocol data unit (BPDU) packets.

If your network is implementing a spanning tree topology across multiples switches, you can configure 3Com Baseline Switch 2250 Plus to forward or to block and discard bridge protocol data unit (BPDU) packets to another switch. Switches that support the spanning tree protocol communicate with each other using BPDU packets.

The spanning tree protocol (STP) is a mechanism that prevents looping and broadcast storms. A spanning tree uses the spanning tree algorithm to detect

Physical Features 9

available communication paths between switches and to determine the best available path and block less optimal paths.

For information on configuring BPDU forwarding and blocking, refer to “

Physical Features

Figure 1 shows the front and rear panels of the

Switch. The numbers in this diagram refer to numbered sections in “

Panel” on page 12.

Figure 1 Front and Rear Panels

Front Panel

The front panel of the Switch contains a series of indicator lights (LEDs) that help describe the state of various networking and connection operations.

(1) 48 RJ-45 Ports

WARNING: RJ-45 Ports. These are shielded RJ-45 data sockets. They cannot be used as standard traditional telephone sockets, or to connect the unit

Spanning Tree” on page 42.

Front Panel” on page 9 and “Rear

to a traditional PBX or public telephone network. Only connect RJ-45 data connectors, network telephony systems, or network telephones to these sockets.

Either shielded or unshielded data cables with shielded or unshielded jacks can be connected to these data sockets.

AVERTISSEMENT: Points d’accès RJ-45. Ceux-ci sont protégés par des prises de données. Ils ne peuvent pas être utilisés comme prises de téléphone conventionnelles standard, ni pour la connection de l’unité à un réseau téléphonique central privé ou public. Raccorder seulement connecteurs de données RJ-45, systèmes de réseaux de téléphonie ou téléphones de réseaux à ces prises.

Il est possible de raccorder des câbles protégés ou non protégés avec des jacks protégés ou non protégés à ces prises de données.

WARNHINWEIS: RJ-45-Porte. Diese Porte sind geschützte Datensteckdosen. Sie dürfen weder wie normale traditionelle Telefonsteckdosen noch für die Verbindung der Einheit mit einem traditionellem privatem oder öffentlichem Telefonnetzwerk gebraucht werden. Nur RJ-45-Datenanscluße, Telefonnetzsysteme or Netztelefone an diese Steckdosen anschließen.

Entweder geschützte oder ungeschützte Buchsen dürfen an diese Datensteckdosen angeschlossen werden.

The Switch has 48 10/100 Mbps autonegotiating ports (ports 1 to 48). Their speed and duplex mode

10 CHAPTER 1: INTRODUCING THE BASELINE SWITCH

(half-duplex or full-duplex) are automatically determined by the capabilities of the connected device.

Each port also supports automatic MDI/MDI-X detection and can be connected to either a 10BASE-T, or a 100BASE-TX device.

CAUTION: The Switch supports full-duplex autonegotiation. If the connected device does not support autonegotiation, the Switch will operate in half-duplex mode (even if the attached device is operating in full-duplex mode).

In such a configuration, you may notice some degradation of network performance. 3Com recommends that you use devices that are capable of autonegotiation (and that you ensure that autonegotiation is enabled, if it is a configurable option). (see “

Troubleshooting” on page 61).

(2) 10/100/1000BASE-T/SFP Ports

Ports 49 and 50 are combination Gigabit RJ-45 ports with shared Small Form Factor Pluggable (SFP) transceiver slots. If an SFP transceiver (purchased separately) is installed in a slot and is active, the associated RJ-45 port of the same number is disabled.

SFP ports are numbered 49 and 50 on the Switch. When an SFP port is active, it has priority over the 10/100/1000 port of the same number. The corresponding 10/100/1000 port is disabled when an SFP transceiver is plugged in.

(3) Link/Activity LEDs

The following tables describe the LEDs visible on the front of the Switch, and how to read their status according to color.

Ta b l e 4 10BASE-T/100BASE-TX Ports

Status Meaning

Green Link established, operating at 100 Mbps

Yellow Link established, operating at 10 Mbps

Flashing Green Packets are being received or

transmitted on the port at 100 Mbps

The 1000BASE-T RJ-45 ports support automatic MDI/MDI-X operation, so you can use straight-through or crossover cables for all network connections to workstations or servers, or to other switches or hubs.

Physical Features 11

Status Meaning

Flashing Yellow Packets are being received or

transmitted on the port at 10 Mbps

Off Link not established, either nothing is

connected to the port, or there is a problem.

■ Verify that the attached device is

powered on

■ Verify that the cable or fiber is the

correct type and is not faulty

■ For fiber connections, ensure that the

receive (RX) and transmit (TX) cable connectors are not swapped

If these checks do not identify the cause of the problem, it may be that the unit or the device connected to the port is faulty. Contact your 3Com network supplier for further advice.

Ta b l e 5 10BASE-T/100BASE-TX/1000BASE-T Ports

Status Meaning

Green Link established, operating at 1000

Mbps

Yellow Link established, operating at 10 or 100

Mbps

Flashing Green Packets are being received or

transmitted on the port at 1000 Mbps

Flashing Yellow Packets are being received or

transmitted on the port at 10 or 100 Mbps

Status Meaning

Flashing Yellow to

Port disabled or link loopback error

Green

Off Link not established, either nothing is

connected to the port, or there is a problem.

■ Verify that the attached device is

powered on

■ Verify that the cable or fiber is the

correct type and is not faulty

■ For fiber connections, ensure that the

receive (RX) and transmit (TX) cable connectors are not swapped

If these checks do not identify the cause of the problem, it may be that the unit or the device connected to the port is faulty. Contact your 3Com network supplier for further advice.

(4) Module Active LEDs

The Module Active LEDs show the status of any SFP modules that are installed.

Ta b l e 6 Module Active LEDs

Status Meaning

Green Fiber SFP is inserted in the slot

Off No fiber SFP is inserted in the slot

12 CHAPTER 1: INTRODUCING THE BASELINE SWITCH

(5) Power LED

The Power LED shows the power status of the Switch.

Ta b l e 7 Power LED

Status Meaning

Green The unit is powered on and ready for use

Flashing Green

Yellow Power-on self-test or loopback test failed. If this

Off The unit is not receiving power:

Power-on self-test is in progress

occurs, reset the Switch to factory defaults. Refer

“Resetting to Factory Defaults”

■ Verify that the power cord is connected cor-

rectly

■ If the unit still does not operate, contact your

3Com network supplier

(6) Self-Adhesive Pads

The unit is supplied with four self-adhesive rubber pads.

Do not apply the pads if you intend to rack-mount the unit.

If the unit is to be part of a free-standing stack, apply the pads to each marked corner area on the underside of the unit. Place the unit on top of the lower unit, ensuring that the pads locate within the recesses of the lower unit.

Rear Panel

(7) Power Supply

The Switch automatically adjusts to the supply voltage. Only use the power cord that is supplied with the unit.

(8) Recovery Button

Use the Recovery button on the rear panel to reset the Switch to its factory defaults. For more information, refer to “

page 61

Package Contents

The 3Com Baseline Switch 2250 Plus package includes the following items:

■ One 3Com Baseline Switch 2250 Plus unit

■ One power cord

■ Four standard height, self-adhesive rubber pads

■ One mounting kit

■ One CD-ROM, which contains this User Guide and

the 3Com Discovery application

■ One warranty flyer

Before installing and using the Switch, verify that your Switch package has all these items. If any of the above items are damaged or missing, contact your 3Com network supplier immediately.

Resetting to Factory Defaults” on

INSTALLING THE SWITCH

This chapter contains information that you need to install and set up the Switch. It covers the following topics:

■ Positioning the Switch

■ Rack-Mounting or Free-Standing

■ Supplying Power to the Switch

■ Connecting a Network Device

■ Performing Spot Checks

Before You Begin

WARNING: Safety Information. Before installing or removing any components from the Switch or carrying out any maintenance procedures, read the safety information provided in Appendix B

AVERTISSEMENT: Consignes de sécurité. Avant d'installer ou d'enlever tout composant du Switch ou d'entamer une procédure de maintenance, lisez les informations relatives à la sécurité qui se trouvent dans Appendix B

WARNHINWEIS: Sicherheitsinformationen. Bevor Sie Komponenten aus dem Switch entfernen oder dem Switch hinzufuegen oder Instandhaltungsarbe-

of this guide.

(l'Appendice B) de ce guide.

iten verrichten, lesen Sie die Sicherheitsanweisungen, die in Appendix B

(Anhang B) in diesem Handbuch

aufgefuehrt sind.

Positioning the Switch

The Switch is suitable for use in an office environment where it can be free-standing or mounted in a standard 19-inch equipment rack.

Alternatively, the Switch can be rack-mounted in a wiring closet or equipment room. A mounting kit, containing two mounting brackets and four screws, is supplied with the Switch.

When deciding where to position the Switch, ensure that:

■ It is accessible and cables can be connected easily.

■ Cabling is away from sources of electrical noise.

These include lift shafts, microwave ovens, and air conditioning units. Electromagnetic fields can interfere with the signals on copper cabling and introduce errors, therefore slowing down your network.

■ 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 (3Com

14 CHAPTER 2: INSTALLING THE SWITCH

recommends that you provide a minimum of 25 mm or 1 in. clearance).

■ The air is as free of dust as possible.

■ Temperature operating limits are not likely to be

exceeded. It is recommended that the unit is installed in a clean, air conditioned environment.

It is always good practice to wear an anti-static wrist strap when installing network equipment, connected to a ground point. If one is not available, try to keep in contact with a grounded rack and avoid touching the unit's ports and connectors, if possible. Static discharge can cause reliability problems in your equipment.

Aufstellen des Switch

Bei der Entscheidung wo Sie den Switch positionieren, stellen Sie sicher das:

■ Der Switch zugänglich ist und die Kabel leicht

angeschlossen werden können.

■ Die Kabel nicht in der nähe von elektrischen

Störquellen befinden. Das schließt Aufzugsschächte, Mikrowellen und Klimaanlagen ein. Elektromagnetische Felder können die Signale in den Kupferleitungen stören, und Fehler verursachen, was die Verlangsamung Ihres Netzwerkes zur Folge haben kann.

■ Weder Wasser noch Feuchtigkeit in das Gehäuse

eindringen kann.

■ Die Luftzirkulation um den Switch und durch die

Öffnungen des Gehäuses nicht behindert wird.

3Com empfiehlt das Sie 25mm (1 Inch) Zwischenraum sicherstellen.

■ Die Luft so frei wie möglich von Staub ist.

■ Es unwahrscheinlich ist das die Betriebstemperatur

überschritten wird. 3Com empfiehlt das Sie den Switch in einer sauberen, klimatisierten Umgebung installieren.

Rack-Mounting or Free-Standing

The unit can be mounted in a 19-inch equipment rack using the supplied mounting kit, (see “

Mounting Kit” on page 14), or it can be free-stand-

ing. Do not place objects on top of the unit or stack.

CAUTION: If installing the Switch in a free-standing stack of different size Baseline or SuperStack the smaller units must be installed above the larger ones. Do not have a free-standing stack of more than six units.

Using the Mounting Kit

The Switch is supplied with two mounting brackets and four screws. These are used for rack mounting the unit. When mounting the unit, take note of the guidelines given in “

page 13

The Switch is 1U (1.75 in.) high and will fit in a standard 19-inch rack.

CAUTION: Before continuing, disconnect all cables from the unit. Remove the self-adhesive pads from the underside of the unit, if already fitted.

Positioning the Switch” on

Using the

3 units,

Rack-Mounting or Free-Standing 15

To rack-mount the Switch:

1 Place the unit the right way up on a hard, flat surface

with the front facing towards you.

2 Locate a mounting bracket over the mounting holes

on one side of the unit.

3 Insert the two screws supplied in the mounting kit

and fully tighten with a suitable screwdriver.

Figure 2 Inserting the Screws

Montagesatz Anweisungen

Der Switch wird mit zwei Halterungen und vier Schrauben geliefert. Diese werden für den Einbau in einem Baugruppenträger benutzt. Bei der Montage der Baugruppe beachten Sie die Anweisungen aus “Aufstellen des Switch“.

Der Switch ist eine Baueinheit hoch und passt in einen Standard 19'' (Zoll) Baugruppenträger.

ACHTUNG: Entfernen Sie alle Kabel, bevor Sie fortfahren. Entfernen Sie die selbstklebenden Polster (Füße) von der Unterseite der Baugruppe, falls diese bereits angebracht sind.

1 Platzieren Sie die Baugruppe aufrecht auf einer

harten, ebenen Fläche mit der Vorderseite zu Ihnen.

2 Ordnen Sie eine der Halterungen über den Löchern

an der Seite der Baugruppe an.

3 Stecken Sie zwei der mitgelieferten Schrauben in die

Löcher und drehen Sie diese mit einem geeigneten Schraubendreher fest.

4 Wiederholen Sie die letzten zwei Schritte auf der

anderen Seite der Baugruppe.

4 Repeat the two previous steps for the other side of

the unit.

5 Insert the unit into the 19-inch rack and secure with

suitable screws (not provided). Ensure that the ventilation holes are not obstructed.

6 Reconnect the network cables.

5 Führen Sie die Baugruppe in den 19" (Zoll) Baugrup-

penträger ein und sichern sie die Baugruppe mit geeigneten Schrauben. (Nicht im Lieferumfang enthalten.)

6 Schließen Sie alle Kabel wieder an.

16 CHAPTER 2: INSTALLING THE SWITCH

Placing Units On Top of Each Other

If the Switch units are free-standing, up to four units can be placed one on top of the other. If you are mixing a variety of Baseline and SuperStack units, the smaller units must be positioned at the top.

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

Supplying Power to the Switch

Power problems can be the cause of serious failures and downtime in your network. Ensure that the power input to your system is clean and free from sags and surges to avoid unforeseen network outages. 3Com recommends that you install power conditioning, especially in areas prone to black outs, power dips and electrical storms.

The unit is intended to be grounded. Ensure it is connected to earth ground during normal use. Installing proper grounding helps to avoid damage from lightning and power surges.

Before powering on the Switch, verify that network cables and the power cable are securely connected.

power is by connecting or disconnecting the power cord.

To power on the Switch:

1 Plug the power cord into the power socket on the

rear panel of the Switch. Refer to “ on page 12

2 Plug the other end of the power cord into a power

for more information.

(7) Power Supply”

outlet.

When the Switch is powered on, the Power LED lights up. If the Power LED does not light up, refer to “

Power LED” on page 12 for more information.

Checking for Correct Operation

After you power on the Switch, it automatically performs a power-on self-test (POST). During POST, the Power LED on the front panel of the Switch flashes green.

When POST is complete, the Power LED turns green. If the Power LED turns yellow after POST, it means that POST failed.

Ta bl e 8

summarizes the possible colors for the Power

LED after POST.

Ta b l e 8 Possible Power LED Colors After POST

Color State

Green The unit is powered on and ready for use

(5)

CAUTION: The Switch has no ON/OFF switch; the only method of connecting or disconnecting main

Connecting a Network Device 17

Color State

Yellow Power-on self-test or loopback test failed.

This can happen if a port or ports fail when the Switch was powered on.

Off The unit is not receiving power:

■ Verify that the power cord is connected

correctly, and then try powering on the Switch again

■ If the Switch still does not operate, con-

tact your 3Com network supplier

If POST fails, try the following:

■ Power off the Switch, and then power it on again.

Check the Power LED and see if POST was successfully completed.

■ Reset the Switch. See “Resetting to Factory

Defaults” on page 61.

CAUTION: Resetting the Switch to its factory defaults erases all your settings. You will need to reconfigure the Switch after you reset it.

If these do not resolve the issue:

■ Check the 3Com Knowledgebase for a solution. To

visit the 3Com Knowledgebase Web site, start your Web browser, and then enter

http://knowledgebase.3com.com

■ Contact your 3Com network supplier for

assistance.

Connecting a Network Device

To connect a network device to the Switch, use Category 5 unshielded or shielded (screened) 100 Ohm TP cables (or Category 3 cables for 10 Mbps connections).

For optimal connections, ensure that the cable length for each connection is not longer than 100 m (328 ft).

Figure 3 Connecting Devices to the Switch

Baseline 10/100 switch

Baseline Switch 2250Plus

1000 Mbps link

10 or 100Mbps link

To connect a device to the Switch:

1 Connect one end of the cable to an RJ-45 port on the

Switch.

2 Connect the other end to the appropriate RJ-45 port

on the connecting device.

Endstations on switched 100 Mbps connections

Endstations on switched 10 or 100Mbps connection

1000 Mbps copper or fiber connection to backbone or server/workstation

Server on switched 1000 Mbps connection

For 1000BASE-T operation, 3Com recommends using Category 5e or 6 cables.

18 CHAPTER 2: INSTALLING THE SWITCH

Using SFP Transceivers

The following sections describe how to insert and remove an SFP transceiver from an SFP slot.

SFP transceivers are hot-insertable and hot-swappable. You can remove them from and insert them into any SFP port without having to power off the Switch.

Approved SFP Transceivers

The following list of approved SFP transceivers is correct at the time of publication:

■ 3CSFP91 SFP (SX)

■ 3CSFP92 SFP (LX)

To access the latest list of approved SFP transceivers for the Switch on the 3Com Corporation World Wide Web site, enter this URL into your Internet browser:

http://www.3com.com

3Com recommends using 3Com SFPs in the Switch. If you insert an SFP transceiver that is not supported, the Switch will not recognize it.

fiber-optic cable or to multimode fiber using a conditioned launch cable.

If the SFP transceiver is faulty, it will not operate within the Switch. See “

page 61

Troubleshooting” on

To insert an SFP transceiver:

1 Hold the transceiver so that the fiber connector is

toward you and the product label is visible, as shown in Figure 4

. Ensure the wire release lever is closed (in

the upright position).

Figure 4 Inserting the SFP Transceiver

Inserting an SFP Transceiver

To be recognized as valid, the SFP transceiver must be one of the following:

■ 1000BASE-SX SFP transceiver – Use this transceiver

to connect the Switch directly to a multimedia fiber-optic cable.

■ 1000BASE-LX SFP transceiver – Use this transceiver

to connect the Switch directly to a single-mode

2 Gently slide the transceiver into the SFP slot until it

clicks into place.

Performing Spot Checks 19

CAUTION: SFP transceivers are keyed and can be properly inserted only one way. If the transceiver does not click when you insert it, remove it, turn it over, and then re-insert it.

3 Remove the plastic protective cover, if fitted.

4 Connect the fiber cable.

5 The transceiver connects to the network using a

duplex LC connector. Attach a male duplex LC connector on the network cable into the duplex LC connector on the transceiver.

6 Connect the other end of the cable to a device fitted

with an appropriate Gigabit Ethernet connection.

7 Check the Module Active LEDs on the front of the

Switch to ensure that it is operating correctly.

Removing an SFP Transceiver

Removing an SFP transceiver does not require powering off the Switch.

To remove an SFP transceiver:

1 Disconnect the cable from the transceiver.

2 Move the wire release lever downwards until it is

pointing toward you.

Performing Spot Checks

At frequent intervals, you should visually check the Switch. Regular checks can give you an early warning of a possible failure; any problems can then be attended to when there will be least effect on users.

3Com recommends periodically checking the items listed in Ta b le 9

Ta b l e 9 Items to Check

Item Verify That

Cabling All external cabling connections are secure

Cooling fan Where possible, check that the cooling fan

If you experience any problems operating the Switch, refer to “

and that no cables are pulled taut

is operating by listening to the unit. The fan is fitted near to the front right hand side of the unit (when viewed from the front).

Troubleshooting” starting on page 61.

3 Pull the wire release lever toward you to release the

catch mechanism.

The SFP transceiver should slide out easily.

20 CHAPTER 2: INSTALLING THE SWITCH

CONNECTING TO THE WEB INTERFACE

The Switch has a built-in Web interface that you can use to set the admin password, change the IP address that is assigned to the Switch, and configure its advanced settings.

If you only want the Switch to function as a basic layer 2 switch, you do not need to access the Web interface and configure the Switch.

This chapter provides information on how to gain access to the Web interface using the Discovery application. It also introduces the menu items and buttons that are available on the Web interface.

The following topics are covered:

■ Requirements for Accessing the Web Interface

■ Running the Discovery Application

■ Logging On to the Web Interface

■ Navigating the Web Interface

Requirements for Accessing the Web Interface

To connect to the Web interface, you need the following:

■ The Discovery application, which is included on the

3Com Baseline Switch 2250 Plus CD-ROM that is supplied with your Switch

■ A computer that is connected to the Switch and

that has a Web browser

Running the Discovery Application

The 3Com Baseline Switch 2250 Plus CD-ROM contains, among others, the Discovery application.

The Discovery application can be used for detecting and connecting to the Switch on the network. The application will launch a Web interface that provides the user with options to configure, modify, and upgrade the Switch.

To use Discovery to connect to the Web interface, do the following:

1 On a computer that is connected to the Switch, insert

the CD-ROM into its CD drive.

Discovery should start automatically. If it does not start automatically, go to the the CD-ROM, and then double-click

\Discovery folder on

discovery.exe.

22 CHAPTER 3: CONNECTING TO THE WEB INTERFACE

The Welcome screen of Discovery appears.

Figure 5 Welcome Screen of Discovery

2 If the computer has multiple network adapters, select

the adapter that connects the computer to the Switch, and then click Next.

If the computer has only one adapter, click Next.

Figure 6 Discovered Devices Screen

3 On the Discovered Devices screen, click Baseline

Switch 2250 Plus, and then click Next.

The Completing the 3Com Discovery Application screen appears.

4 Click Finish.

Discovery searches the network for 3Com devices. When detection is complete, the Discovered Devices screen displays detected network devices.

The logon dialog box for the Web interface appears.

Logging On to the Web Interface 23

Logging On to the Web Interface

After the Web interface loads in your Web browser, the first page that appears is the logon screen. On this screen, you need to enter the administration user name and password to gain access to the Web interface.

The browser’s address bar also displays the IP address that the Switch is currently using.

Figure 7 Logon Dialog Box

To log on to the Web interface:

Navigating the Web Interface

The Web interface has been designed to enable you to easily perform advanced configuration tasks and view information about the Switch.

Buttons

Depending on the screen that is currently displayed, the following buttons may appear:

■ Apply – Click to save and apply any changes that

you have made

■ Cancel – Click to discard any unsaved changes

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