Canton Switch 3C16476CS User Manual

Baseline Switch 2250 Plus

User Guide

Installationsanleitung

3C16476CS

http://www.3com.com/

Part No. 10015237 Rev. AA

Published August 2006

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CONTENTS

Supplying Power to the Switch 16

Checking for Correct Operation 16

Connecting a Network Device 17

Using SFP Transceivers 18

ABOUT THIS GUIDE

Conventions

Related Documentation

In addition to this guide, each 3Com Baseline Switch

2250 Plus documentation set includes the following:

■ Online Help – Accessible from the Web interface,

provides information that helps you perform tasks

using the Web interface.

■ Release Notes – Provide information about the

current software release, including new features,

modifications, and known problems.

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:

[email protected]

Please include the following information when con-

tacting us:

■ Document title

■ Document part number (on the title page)

■ Page number (if appropriate)

Example:

■ 3Com Baseline Switch 2250 Plus User Guide

■ Part number: 10015237

■ Page 25

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INTRODUCING THE BASELINE SWITCH

This chapter provides an overview of the features and

capabilities of the 3Com^®Baseline Switch 2250 Plus.

It also identifies the contents of the Switch package

and helps you get to know the physical features of

the device.

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.

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.

Any port can therefore be used to connect to another

switch port, server, or workstation without additional

configuration.

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.

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

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.

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.

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CHAPTER 1: INTRODUCING THE BASELINE SWITCH

type of traffic. The priority levels and their traffic types

are shown in the following table.

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

Table 3 Priority Levels for Traffic Types

Priority Level

Traffic Type

Best effort

between the Switch and a 1000 Mbps core network.

Background

When an SFP port is in operation, the corresponding

10/100/1000BASE-T port is disabled.

Standard (spare)

Excellent effort (business critical)

Controlled load (streaming multimedia)

Traffic Prioritization

Video (interactive media), less than 100

milliseconds latency and jitter

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 pri-

ority 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.

Voice (interactive voice), less than 10

milliseconds latency and jitter.

Network control reserved traffic

Forwarding of BPDU Packets

Within an extended local area network that imple-

ments a spanning tree protocol topology, switches

communicate with each other using bridge protocol

data unit (BPDU) packets.

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

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

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Physical Features

available communication paths between switches and

to determine the best available path and block less

optimal paths.

to a traditional PBX or public telephone network.

Only connect RJ-45 data connectors, network

telephony systems, or network telephones to these

sockets.

For information on configuring BPDU forwarding and

blocking, refer to “Spanning Tree” on page 41.

Either shielded or unshielded data cables with

shielded or unshielded jacks can be connected to

these data sockets.

Physical Features

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.

Figure 1 shows the front and rear panels of the

Switch. The numbers in this diagram refer to num-

bered sections in “Front Panel” on page 9 and “Rear

Panel” on page 12.

Figure 1 Front and Rear Panels

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.

Front Panel

The front panel of the Switch contains a series of indi-

cator lights (LEDs) that help describe the state of vari-

ous networking and connection operations.

Entweder geschützte oder ungeschützte Buchsen

dürfen an diese Datensteckdosen angeschlossen

werden.

(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

The Switch has 48 10/100 Mbps autonegotiating

ports (ports 1 to 48). Their speed and duplex mode

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CHAPTER 1: INTRODUCING THE BASELINE SWITCH

(half-duplex or full-duplex) are automatically

determined by the capabilities of the connected

device.

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 remote 1000 Mbps

workgroups or to create a high-capacity aggregated

link backbone connection.

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).

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.

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 59).

(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.

Table 4 10BASE-T/100BASE-TX Ports

Status

Meaning

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

Green

Link established, operating at 100 Mbps

Link established, operating at 10 Mbps

Ports 49 and 50 are combination Gigabit RJ-45 ports

with shared Small Form Factor Pluggable (SFP) trans-

ceiver slots. If an SFP transceiver (purchased sepa-

rately) is installed in a slot and is active, the associated

RJ-45 port of the same number is disabled.

Yellow

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.

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Physical Features

Status

Meaning

Status

Meaning

Flashing Yellow

Packets are being received or

transmitted on the port at 10 Mbps

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.

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 attached device is

powered on

■ Verify that the cable or fiber is the

correct type and is not faulty

■ 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

■ 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.

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.

Table 5 10BASE-T/100BASE-TX/1000BASE-T Ports

(4) Module Active LEDs

Status

Meaning

The Module Active LEDs show the status of any SFP

modules that are installed.

Green

Link established, operating at 1000

Mbps

Table 6 Module Active LEDs

Yellow

Link established, operating at 10 or 100

Mbps

Status

Green

Off

Meaning

Fiber SFP is inserted in the slot

No fiber SFP is inserted in the slot

Flashing Green

Flashing Yellow

Packets are being received or

transmitted on the port at 1000 Mbps

Packets are being received or

transmitted on the port at 10 or 100

Mbps

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CHAPTER 1: INTRODUCING THE BASELINE SWITCH

(5) Power LED

Rear Panel

(7) Power Supply

The Power LED shows the power status of the Switch.

Table 7 Power LED

The Switch automatically adjusts to the supply volt-

age. Only use the power cord that is supplied with

the unit.

Status

Meaning

Green

The unit is powered on and ready for use

Power-on self-test is in progress

Flashing

Green

(8) Recovery Button

Yellow

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

occurs, reset the Switch to factory defaults. Refer

to “Resetting to Factory Defaults”

Use the Recovery button on the rear panel to reset

the Switch to its factory defaults. For more informa-

tion, refer to “Resetting to Factory Defaults” on

page 59.

Off

The unit is not receiving power:

■ Verify that the power cord is connected cor-

rectly

■ If the unit still does not operate, contact your

3Com network supplier

Package Contents

The 3Com Baseline Switch 2250 Plus package

includes the following items:

(6) Self-Adhesive Pads

■ One 3Com Baseline Switch 2250 Plus unit

■ One power cord

The unit is supplied with four self-adhesive rubber

pads.

■ Four standard height, self-adhesive rubber pads

■ One mounting kit

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

the unit.

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

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 with the

recesses of the lower unit.

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.

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INSTALLING THE SWITCH

This chapter contains information that you need to

install and set up the Switch. It covers the following

topics:

iten verrichten, lesen Sie die Sicherheitsanweisungen,

die in Appendix B (Anhang B) in diesem Handbuch

aufgefuehrt sind.

■ Positioning the Switch

Positioning the Switch

■ Rack-Mounting or Free-Standing

■ Supplying Power to the Switch

■ Connecting a Network Device

■ Performing Spot Checks

The Switch is suitable for use in an office environment

where it can be free-standing or mounted in a stan-

dard 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.

Before You Begin

When deciding where to position the Switch, ensure

that:

WARNING: Safety Information. Before installing or

removing any components from the Switch or carry-

ing out any maintenance procedures, read the safety

information provided in Appendix B of this guide.

■ 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.

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 (l'Appendice B) de ce guide.

■ Water or moisture cannot enter the case of the

unit.

WARNHINWEIS: Sicherheitsinformationen. Bevor

Sie Komponenten aus dem Switch entfernen oder

dem Switch hinzufuegen oder Instandhaltungsarbe-

■ Air flow around the unit and through the vents in

the side of the case is not restricted (3Com

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CHAPTER 2: INSTALLING THE SWITCH

recommends that you provide a minimum of 25

mm or 1 in. clearance).

3Com empfiehlt das Sie 25mm (1 Inch)

Zwischenraum sicherstellen.

■ The air is as free of dust as possible.

■ Die Luft so frei wie möglich von Staub ist.

■ Temperature operating limits are not likely to be

exceeded. It is recommended that the unit is

installed in a clean, air conditioned environment.

■ Es unwahrscheinlich ist das die Betriebstemperatur

überschritten wird. 3Com empfiehlt das Sie den

Switch in einer sauberen, klimatisierten Umgebung

installieren.

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 dis-

charge can cause reliability problems in your equip-

ment.

Rack-Mounting or Free-Standing

The unit can be mounted in a 19-inch equipment rack

using the supplied mounting kit, (see “Using the

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^®3 units,

the smaller units must be installed above the larger

ones. Do not have a free-standing stack of more than

six units.

Aufstellen des Switch

Bei der Entscheidung wo Sie den Switch position-

ieren, stellen Sie sicher das:

■ Der Switch zugänglich ist und die Kabel leicht

angeschlossen werden können.

Using the Mounting Kit

■ Die Kabel nicht in der nähe von elektrischen

Störquellen befinden. Das schließt

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 “Positioning the Switch” on

page 13.

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.

The Switch is 1U (1.75 in.) high and will fit in a stan-

dard 19-inch rack.

■ Weder Wasser noch Feuchtigkeit in das Gehäuse

eindringen kann.

CAUTION: Before continuing, disconnect all cables

from the unit. Remove the self-adhesive pads from

the underside of unit, if already fitted.

■ Die Luftzirkulation um den Switch und durch die

Öffnungen des Gehäuses nicht behindert wird.

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Rack-Mounting or Free-Standing

To rack-mount the Switch:

Montagesatz Anweisungen

Der Switch wird mit zwei Halterungen und vier

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

Schrauben geliefert. Diese werde für den Einbau in

einen Baugruppenträger benutzt. Bei der Montage

der Baugruppe beachten Sie die Anweisungen aus

“Aufstellen des Switch“.

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

Der Switch ist eine Baueinheit hoch und passt in einen

Standard 19'' (Zoll) Baugruppenträger.

and fully tighten with a suitable screwdriver.

Figure 2 Inserting the Screws

ACHTUNG: Entfernen Sie alle Kabel, bevor Sie fort-

fahren. Entfernen Sie die selbstklebenden Polster

(Füße) von der Unterseite der Baugruppe, falls diese

bereits angebracht sind.

1 Plazieren Sie die Baugruppe aufrecht auf einer harten,

Baseline

Switch

2816-SFP

Plus

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 Widerholen Sie letzten beiden Schritte auf der

anderen Seite der Baugruppe.

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

penträger ein und sichern sie die Baugruppe mit

geeigneten Schrauben. (Nicht im Lieferumfang

enthalten.)

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 ventila-

tion holes are not obstructed.

6 Schließen Sie alle Kabel wieder an.

6 Reconnect the network cables.

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CHAPTER 2: INSTALLING THE SWITCH

power is by connecting or disconnecting the power

cord.

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.

To power on the Switch:

1 Plug the power cord into the power socket on the

rear panel of the Switch. Refer to “(7) Power Supply”

on page 12 for more information.

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 cor-

ner. 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.

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

outlet.

When the Switch is powered on, the Power LED lights

up. If the Power LED does not light up, refer to “(5)

Power LED” on page 12 for more information.

Checking for Correct Operation

Supplying Power to the Switch

After you power on the Switch, it automatically per-

forms a power-on self-test (POST). During POST, the

Power LED on the front panel of the Switch flashes

green.

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 out-

ages. 3Com recommends that you install power con-

ditioning, especially in areas prone to black outs,

power dips and electrical storms.

When POST is complete, the Power LED turns green.

If the Power LED turns yellow after POST, it means

that POST failed.

The unit is intended to be grounded. Ensure it is con-

nected to earth ground during normal use. Installing

proper grounding helps to avoid damage from light-

ning and power surges.

Table 8 summarizes the possible colors for the Power

LED after POST.

Table 8 Possible Power LED Colors After POST

Color

State

Before powering on the Switch, verify that network

cables and the power cable are securely connected.

Green

The unit is powered on and ready for use

CAUTION: The Switch has no ON/OFF switch; the

only method of connecting or disconnecting main

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Connecting a Network Device

Color

State

Connecting a Network Device

Yellow

Power-on self-test or loopback test failed.

This can happen if a ports or ports fail

when the Switch was powered on.

To connect a network device to the Switch, use Cate-

gory 5 unshielded or shielded (screened) 100 Ohm TP

cables (or Category 3 cables for 10 Mbps connec-

tions).

Off

The unit is not receiving power:

■ Verify that the power cord is connected

correctly, and then try powering on the

Switch again

For optimal connections, ensure that the cable length

for each connection is not longer than 100 m (328 ft).

■ If the Switch still does not operate, con-

tact your 3Com network supplier

Figure 3 Connecting Devices to the Switch

Endstations on switched

Baseline 10/100 switch

100 Mbps connections

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.

Endstations on switched

100 Mbps connections

Baseline 10/100 switch

■ Reset the Switch. See “Resetting to Factory

Defaults” on page 59.

1000 Mbps copper

or fiber connection

to backbone or

Baseline Switch 2250 Plus

CAUTION: Resetting the Switch to its factory defaults

erases all your settings. You will need to reconfigure

the Switch after you reset it.

server/workstation

Endstations

on switched

10 or 100 Mbps

connection

1000 Mbps link

10 or 100 Mbps link

If these do not resolve the issue:

Server on switched

1000 Mbps

connection

■ Check the 3Com Knowledgebase for a solution. To

visit the 3Com Knowledgebase Web site, start your

Web browser, and then enter

To connect a device to the Switch:

http://knowledgebase.3com.com

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

■ Contact your 3Com network supplier for

Switch.

assistance.

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

on the connecting device.

For 1000BASE-T operation, 3Com recommends using

Category 5e or 6 cables.

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CHAPTER 2: INSTALLING THE SWITCH

fiber-optic cable or to multimode fiber using a

conditioned launch cable.

Using SFP Transceivers

The following sections describe how to insert and

remove an SFP transceiver from an SFP slot.

If the SFP transceiver is faulty, it will not operate

within the Switch. See “Troubleshooting” on

page 59.

SFP transceivers are hot-insertable and hot-swappa-

ble. You can remove them from and insert them into

any SFP port without having to power off the Switch.

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).

Approved SFP Transceivers

The following list of approved SFP transceivers is cor-

rect at the time of publication:

Figure 4 Inserting the SFP Transceiver

■ 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 on the Switch.

If you insert an SFP transceiver that is not supported,

the Switch will not recognize it.

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.

2 Gently slide the transceiver into the SFP slot until it

clicks into place.

■ 1000BASE-LX SFP transceiver – Use this transceiver

to connect the Switch directly to a single-mode

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Performing Spot Checks

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.

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.

3 Remove the plastic protective cover, if fitted.

4 Connect the fiber cable.

3Com recommends periodically checking the items

listed in Table 9.

5 The transceiver connects to the network using a

duplex LC connector. Attach a male duplex LC con-

nector on the network cable into the duplex LC con-

nector on the transceiver.

Table 9 Items to Check

Item

Verify That

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

Cabling

All external cabling connections are secure

and that no cables are pulled taut

with an appropriate Gigabit Ethernet connection.

Cooling fan

Where possible, check that the cooling fan

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).

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 power-

ing off the Switch.

If you experience any problems operating the Switch,

refer to “Troubleshooting” starting on page 59.

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.

3 Pull the wire release lever toward you to release the

catch mechanism.

The SFP transceiver should slide out easily.

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CHAPTER 2: INSTALLING THE SWITCH

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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.

Requirements for Accessing the Web Interface

To connect to the Web interface, you need the

following:

■ The Discovery application, which is included on

3Com Baseline Switch 2250 Plus CD-ROM that is

supplied with your Switch

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.

■ A computer that is connected to the Switch and

This chapter provides information on how the 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.

that has a Web browser

Running the Discovery Application

The 3Com Baseline Switch 2250 Plus CD-ROM

contains, among others, the Discovery application.

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

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 ^\Discoveryfolder on

the CD-ROM, and then double-click ^{discovery.exe}.

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CHAPTER 3: CONNECTING TO THE WEB INTERFACE

Figure 6 Discovered Devices Screen

The Welcome screen of Discovery appears.

Figure 5 Welcome Screen of Discovery

3 On the Discovered Devices screen, click Baseline

Switch 2250 Plus, and then click Next.

2 If the computer has multiple network adapters, select

the adapter that connects the computer to the

Switch, and then click Next.

The Completing the 3Com Discovery Application

screen appears.

4 Click Finish.

If the computer has only one adapter, click Next.

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.

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Logging On to the Web Interface

Navigating 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 Web interface has been designed to enable you

to easily perform advanced configuration tasks and

view information about the Switch.

The menu is located on the left side of the Web

interface. When you click an item on the menu, the

related screen appears in the main part of the

interface. Some menu items will give you sub-menu

tabs to choose from.

The logon screen also displays the IP address that the

Switch is currently using.

Figure 7 Logon Dialog Box

Figure 8 Switch Screen Layout

Sub-Menu Tabs

To log on to the Web interface:

1 In User name, type admin.

2 Leave the Password field blank.

3 Click OK.

System Information

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CHAPTER 3: CONNECTING TO THE WEB INTERFACE

Table 10 lists the available items on the menu.

Menu Item

Description

SNMP

Contains tabs that allow you to:

■ Display SNMP summary information.

■ Enable or disable SNMP.

Table 10 Available Menu Items

Menu Item

Description

Device Summary

Contains tabs that allow you to:

■ Add community strings.

■ Provide a summary of the Switch’s basic

settings and versions of current

components.

■ Remove community strings.

Device

VLAN

Configures the device.

■ Set the polling interval in seconds.

Contains tabs that allow you to:

■ Create a VLAN.

■ Display the description for each color

coded port.

■ Modify a VLAN.

Save Configuration

Administration

IP Setup

Saves the Switch’s configuration.

Manages the device.

■ Modify VLAN membership for a port.

■ Rename a VLAN.

Allows you to setup, modify, or view the IP

configuration parameters.

■ Remove a VLAN.

■ Display VLAN membership for a port.

■ Display VLAN information.

Backup Configuration Allows you to backup the Switch’s

configuration.

Spanning Tree

IGMP Snooping

IGMP Query

Allows you to configure a Spanning Tree

Protocol.

Restore Configuration Allows you to restore a saved configuration.

Firmware Upgrade

Allows you to upgrade the current firmware

via HTTP.

Allows you to enable or disable IGMP

snooping.

Initialize

Allows you to reset the Switch to factory

default settings.

Allows you to enable or disable IGMP query

mode.

Reboot

Allows you to perform system reboot.

Broadcast Storm

Allows you to enable or disable rate

limiting.

System Access

Contains tabs that allow you to:

■ Display user summary information.

■ Create a new user.

Port

Configures the ports.

Administration

Contains tabs that allow you to:

■ Modify existing users.

■ Display selected port information for the

entire Switch.

■ Remove existing users.

System Time

Allows you to set the system time.

■ Display individual port information.

■ Modify the port settings.

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Navigating the Web Interface

Menu Item

Description

Menu Item

Description

Link Aggregation

Contains tabs that allow you to:

■ Display link aggregation summary.

■ Create an aggregation group.

■ Modify the port memberships.

■ Remove an aggregation group.

802.1X Settings

Contains tabs that allow you to:

■ Display 802.1X information.

■ Display 802.1X detailed information per

port.

■ Configure 802.1X settings.

Monitoring

Display Switch monitoring information.

Spanning Tree per

Port

Contains tabs that allow you to:

Address Table

Displays MAC address table information for

ports and VLANs.

■ Display selected spanning tree

information for every port.

■ Display individual port spanning tree

Cable Diagnostics

Contains tabs that allow you to:

information.

■ Display selected cable diagnostics

■ Modify the spanning tree settings for a

information for all ports.

port.

■ Display all cable diagnostics information

per port.

Port Mirroring

Statistics

Monitor traffic going in and out of ports.

Display statistics for a selected port.

Configures QoS settings.

Help

Direct link to help pages.

QoS

Buttons

VoIP Traffic Setting

Contains tabs that allow you to:

Depending on the screen that is currently displayed,

the following buttons may appear:

■ Display Voice VLAN summary.

■ Configure Voice VLAN global settings.

■ Configure Voice VLAN port settings.

■ Apply – Click to save and apply any changes that

you have made

■ Display port information for Voice VLAN

and Trunk details.

■ Cancel – Click to discard any unsaved changes

■ Display OUI summary.

■ Add or remove OUI.

Security

Configures security settings.

Radius Client

Contains tabs that allow you to:

■ Display Radius Client information.

■ Configure Radius Client settings and set

authentication parameters.

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CHAPTER 3: CONNECTING TO THE WEB INTERFACE

Manually Assigned (Static) IP Address

Accessing the Interface Without Using

Discovery

If you assigned a static IP address to the Switch, you

need to use that IP address to access the Web

interface the next time you want to configure the

Switch.

The Discovery application works by automatically

detecting the IP address that is assigned to the

Switch, and then using that address to connect to the

Web interface. If you know the Switch’s IP address,

you can access the Web interface without using

Discovery.

For example, if you assigned the Switch the IP address

192.168.0.123, start your Web browser, and then

type ^{http://192.168.0.123}.

This section describes how to access the interface

directly, without using Discovery.

If you do not configure the Switch’s IP address

settings, it will perform auto IP configuration to

assign an IP address to itself. For more information,

refer to “Automatic IP Configuration” on page 29.

To determine the IP address that the Switch will assign

to itself during auto IP configuration, check the

sticker on the base of the Switch. This sticker contains

the MAC address and default IP address of the

Switch.

DHCP Assigned IP Address

If you set the IP address mode to DHCP, check the

DHCP server for the IP address that is assigned to the

Switch, and then use that IP address to access the

Web interface.

For example, if the DHCP server assigned the IP

address 192.168.0.123 to the Switch, start your Web

browser, and then type ^{http://192.168.0.123}.

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CONFIGURING THE SWITCH

This chapter provides information on how to

configure the Switch’s advanced features. Topics

include:

Device Summary Information

The Device Summary screen, which automatically

loads after you log on to the Web interface, provides

a snapshot of the Switch’s basic settings and versions

of current components.

■ Device Summary Information

■ Administration Settings

■ Configuring VLANs

■ Configuring Port Settings

■ QoS VoIP Traffic Settings

■ Security

Click Device Summary on the menu. A screen appears

with three tabs that include:

■ Device View

■ Polling Interval

■ Color Key

■ Monitoring

Device View

Configuration Overview

Contains fields that display the system, switch, and

management switch information to identify the

Switch. The fields include Product Description, System

Location, System Contact, Serial Number, Product 3C

Number, MAC Address, Software Version, Unit

Uptime, Bootroom Version, and Hardware Version.

The Switch is shipped ready for use. 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.

You only need to access the Web interface if you

want to:

■ Set the administration password to the Web

interface

■ Assign an IP address to the Switch

■ Configure the Switch’s advanced features

■ Upgrade the firmware

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CHAPTER 4: CONFIGURING THE SWITCH

Figure 9 Device View

To set the polling interval:

1 Click the Device Summary menu, click Polling Interval

tab.

2 Enter a number between 10 to 180 seconds for the

polling interval. Enter a 0 to disable polling.

Color Key

Description of the color coding.

Figure 11 Color Key

If you request for technical assistance from 3Com

Support, you may be asked to print out the

information on this screen.

Polling Interval

Enter the interval in seconds you would like the

Switch to refresh. (Range: 10 to 180 seconds; 0 to

disable polling).

Figure 10 Device View

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Administration Settings

To determine the exact IP address that the Switch

Administration Settings

assigns to itself during auto IP configuration, check

the sticker on the base of the Switch. This sticker

contains the MAC address and default IP address of

the Switch.

The Administration menu includes eight

administration items:

■ IP Setup

To detect its IP information using the automatic

configuration process, the Switch goes through the

following sequence of steps:

■ Backup Configuration

■ Restore Configuration

■ Firmware Upgrade

■ Initialize

1 The Switch tries to configure itself with the default IP

address ^169.254.x.y, where xand yare converted

from the last two bytes of its MAC address.

■ Reboot

For example, if the MAC address is ^08004E000102, the

IP address would be ^169.254.1.2. This address is used

if the Switch is operating in a standalone mode, or no

other switches on the network have this IP address.

■ System Access

■ System Time

■ SNMP

The Switch also assigns the subnet mask 255.255.0.0

(default class B mask) to itself.

Modifying the IP Address Settings

To enable devices on the network to communicate

with the Switch, you need to assign an IP address to it

— either by DHCP or by assigning a static IP address.

2 If this default IP address is already in use on the

network, then the Switch detects this, and increments

the last byte of the MAC address by one to generate

its IP address.

By default, the Switch performs automatic IP

configuration and assigns an IP address to itself. This

is necessary for the Discovery application to be able to

connect to the Web interface.

The IP address would therefore become ^169.254.1.3.

3 The Switch repeats step 2 until an unused IP address

is found.

3Com recommends using automatic IP configuration

only for the initial setup. Once you gain access to the

Web interface, you should assign an IP address to the

Switch (either by using DHCP or assigning a static IP

address) to ensure successful communication

Automatic IP Configuration

When you power on the Switch for the first time, it

automatically uses the default IP address ^169.254.x.y,

where ^xand yare the last two bytes of its MAC

address.

between the Switch and other network devices.

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CHAPTER 4: CONFIGURING THE SWITCH

IP Setup

Backup Configuration

To save the Switch configuration settings:

To set the IP address for the Switch:

1 Click Administration, then IP Setting on the menu.

The IP Settings screen appears. Follow the IP Setup

Wizard to complete the setup.

1 Click Administration, then Backup Configuration on

the menu. The Backup Configuration screen appears.

Figure 13 Backup Configuration

This wizard can also be used to set system name,

location and contact information.

Figure 12 IP Settings Screen

2 Click OK. You will be prompted to provide a location

where the configuration file will be saved.

Restore Configuration

To reload configuration settings that you previously

saved to a file:

1 Click Administration, then Restore Configuration on

the menu. The Restore Configuration screen appears.

Figure 14 Restore Configuration

2 Click Browse to locate the backup file on your

computer to restore the configuration settings.

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Administration Settings

3 Click Restore to copy the configuration back to the

You may need to change the file type in the dialog

box displayed by your Web browser to *.* to be able

to see the file.

Switch.

For security purposes, restoring the configuration

does not change the password.

The file will be copied to the Switch, and once this

has completed, the Switch will restart. Although the

upgrade process has been designed to preserve your

configuration settings, 3Com recommends that you

make a backup of the configuration beforehand, in

case the upgrade process fails for any reason (for

example, the connection between the computer and

the Switch is lost while the new firmware is being

copied to the Switch).

Firmware Upgrade

The Upgrade facility allows you to install on the

Switch any new releases of system firmware that

3Com may make available.

Newer versions of firmware can be downloaded via

HTTP and copied to the Switch; the Switch will restart

and apply the newer system firmware version.

A progress screen displays while the upgrade is taking

place.

Figure 15 Upgrade Screen

The upgrade procedure can take a few minutes, and

is complete when the progress bar has finished

running and the Power LED has stopped flashing and

is permanently green.

CAUTION: Do not interrupt power to the Switch

during the upgrade procedure. If you do, the

firmware may be corrupted and the Switch may not

start up properly afterwards.

1 Click Administration, then Firmware Upgrade on the

Initialize

menu. The Firmware Upgrade screen appears.

To reset the Switch to factory default settings:

2 Once you have downloaded the firmware, use the

Browse button to locate the file on your computer,

and then click OK.

1 Click Administration, then Initialize on the menu.

You will lose all your configuration changes. The

Switch LAN IP address will revert to the default IP

address 169.254.x.y. (see “Automatic IP

Configuration” on page 29). You may need to restart

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CHAPTER 4: CONFIGURING THE SWITCH

your computer to re-establish communication with

the Switch.

To ensure that unauthorized users do not access the

Web interface, 3Com recommends that you set an

admin password when you first configure the Switch.

Reboot

Clicking on Administration, then Reboot on the menu

Even if you do not intend to actively manage the

switch, 3Com recommends that you change the

password to prevent unauthorized access to your

network.

has the same effect as power cycling the unit. No

configuration information will be lost. Reboot the

Switch if you are experiencing problems and you

want to re-establish your Internet connection.

The password can be up to 8 characters long and is

case-sensitive.

Any network users that are currently accessing the

Internet will have their access interrupted while the

reboot takes place, and they may need to restart their

computers when the reboot has completed and the

Switch is operational again.

If you forget the administration password after you

set it, refer to “Forgotten Password” on page 59 for

information on how to regain access to the Web

interface.

User Summary

System Access

Displays the list of user names and their access level.

Click Administration, then System Access on the

menu. A screen appears with four system access tabs:

Figure 16 User Summary Screen

■ User Summary

■ Create User

■ Modify User

■ Remove User

To prevent unauthorized users from accessing the

Web interface and modifying the Switch’s settings,

the interface is password-protected.

The default admin account settings are:

■ User name – admin

■ Password – blank (no password)

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Administration Settings

Figure 18 Modify User Screen

Create User

This page allows you to create a user and define the

access level and password for that user.

Figure 17 CreateUser Screen

Remove User

To remove a user from the Switch, click on the user

name, then click Remove.

Modify User

Figure 19 Remove User Screen

This page allows you to modify a user’s access level

and password.

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CHAPTER 4: CONFIGURING THE SWITCH

Summary

System Time

Click Administration, then System Time on the menu.

Displays the list community access strings.

This screen allows you to set the system time. You can

set the Year, Month, Day, Hours, Minutes, and

Seconds.

Figure 21 SNMP Summary Screen

Figure 20 System Time Screen

Setup

SNMP

Enable or disable the SNMP Agent Status.

Simple Network Management Protocol (SNMP) is a

communication protocol designed specifically for

managing devices on a network. Equipment

Figure 22 SNMP Setup Screen

commonly managed with SNMP includes switches,

routers and host computers. SNMP is typically used to

configure these devices for proper operation in a

network environment, as well as to monitor them to

evaluate performance or detect potential problems.

Click Administration, then SNMP on the menu. A

screen appears with four system access tabs:

SNMP Add

■ Summary

■ Setup

This page allows you to create community strings for

management access.

■ SNMP Add

■ SNMP Remove

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Configuring VLANs

Figure 23 SNMP Add Screen

Configuring VLANs

A virtual LAN (VLAN) is a collection of network nodes

that share the same collision domain, regardless of

their physical location or connection point in the

network. A VLAN serves as a logical workgroup with

no physical barriers, and allows users to share

information and resources as though located on the

same LAN.

You can use the Switch to create VLANs to organize

any group of ports into separate broadcast domains.

VLANs confine broadcast traffic to the originating

group and help eliminate broadcast storms in large

networks. This also provides for a more secure and

cleaner network environment.

SNMP Remove

You can create up to 64 VLANs, add specific ports to

a chosen VLAN (so that the port can only

This page allows you to remove community strings.

communicate with other ports on the VLAN), or

configure a port make it a member of all VLANs.

Figure 24 SNMP Remove Screen

Communication between different VLANs can only

take place if they are all connected to a router or layer

3 switch.

The Device menu includes five items:

■ VLAN

■ Spanning Tree

■ IGMP Snooping

■ IGMP Query

■ Broadcast Storm

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CHAPTER 4: CONFIGURING THE SWITCH

Available option on the Setup screen include:

VLAN

■ VLAN ID – ID of configured VLAN (1-4094, no

Click Device, then VLAN on the menu. A screen

appears with seven tabs that include:

leading zeroes)

■ Setup

For examples on setting up VLANs, refer to “Sample

VLAN Configurations”.

■ Modify VLAN

■ Modify Port

■ Rename

CAUTION: At least one port must always be an

untagged member of VLAN 1 (the management

VLAN). If you choose to connect all ports to VLANs

other than VLAN 1, you will no longer be able to

access the Web interface. If this happens, you will

need to reset the Switch to factory settings.

■ Remove

■ Port Detail

■ VLAN Detail

By default, all ports belong to VLAN 1 as an untagged

member. However, they can belong to multiple VLANs

as a tagged member. Also, newly created VLANs will

initially have no ports associated with them.

Setup

Use the Setup screen to create VLANs on the Switch.

To propagate information about VLAN groups used

on this Switch to external devices, you must specify a

VLAN ID for each VLAN.

Modify VLAN

Use the Modify VLAN screen to change the VLAN to

which a port belongs, and configure the port to

communicate with all other VLANs, or a selected

VLAN.

Figure 25 Setup Screen

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Configuring VLANs

Figure 26 Modify VLAN Screen

Modify Port

Use the Modify Port screen to modify the VLAN

membership of a port.

Figure 27 Modify Port Screen

1 Select a membership use. Available options for each

port include (only one option can be associated with a

single port):

1 Enter a set of VLANs or select all VLANs to configure,

then click Select.

■ Not a member

2 From the drop down menu, select a VLAN to modify.

■ Tagged

3 Select a membership use. Available options for each

port include (only one option can be associated with a

single port):

■ Untagged

2 Select a port to associate with the membership.

■ Tagged

3 Enter a VLAN to apply these changes to, then click

Apply.

■ Untagged

4 Select ports to associate with the membership, then

click Apply.

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CHAPTER 4: CONFIGURING THE SWITCH

Rename

Remove

Use the Rename screen to change the name of a

VLAN.

Use the Remove screen to remove a VLAN.

Figure 29 Remove Screen

Figure 28 Rename Screen

1 Enter a set of VLANs or select all VLANs to add to the

remove list, then click Select.

1 Enter a set of VLANs or select all VLANs to add to the

rename list, then click Select.

2 From the list of selected VLANs choose a VLAN to

remove, or click the Select All button to select all the

VLANs. Click Remove to remove the VLAN.

2 From the list of selected VLANs, choose a VLAN to

rename. Enter a new VLAN name and click Apply.

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Configuring VLANs

Figure 31 VLAN Detail Screen

Port Detail

Choose a port to display the tagged and untagged

VLAN memberships it is associated with.

Figure 30 Port Detail Screen

VLAN Detail

Forwarding Tagged/Untagged Frames

Use this screen to display detailed VLAN information.

Each port on the Switch is capable of passing tagged

or untagged frames.

1 Enter a set of VLANs or select all VLANs to add to the

details list, then click Select.

The following describes how the Switch will handle

tagged and untagged frames.

2 From drop down menu, choose a VLAN to display the

tagged and untagged VLAN memberships it is

associated with the ports on the switch.

■ When a port receives a tagged frame with a VLAN

ID and the port is a member (untagged or tagged)

of that VLAN, the frame is accepted. Otherwise the

if the port is not a member of that VLAN, the

frame is discarded.

■ When a port receives an untagged frame and the

port is an untagged member of a VLAN, the frame

is accepted and assigned to that VLAN ID.

Otherwise if the port is not an untagged member

of any VLAN, the frame is discarded.

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CHAPTER 4: CONFIGURING THE SWITCH

The Switch will only forward a frame to ports that are

members (tagged or untagged) of the VLAN to which

the frame is assigned. If the port is an untagged

member, the egress frame will be stripped of the

VLAN tag and forwarded as untagged. However, if

the port is a tagged member, the egress frame is

forwarded as tagged.

VLAN1 and the ports on VLAN2 cannot communicate

with each other, do the following:

1 Create a new VLAN and set the VLAN ID to 2. Refer

to “Setup” for instructions. VLAN1 is the default

VLAN and already exists.

2 Set ports 1, 3, and 26 to associate with the Untagged

membership in VLAN2.

3 Click Apply.

Sample VLAN Configurations

To illustrate how you can segment network devices

that are connected to the Switch, the following

sample configurations are provided.

Ports 1, 3, and 26 now belong to VLAN2, and will not

communicate with any other ports, unless you add

other ports to the VLAN or change the port

configuration.

Setting Up Two VLANs on the Same Switch

Figure 32 illustrates how you can set up a simple

VLAN on the Switch using desktop connections.

Setting Up VLAN Across Two Switches

This example explains how you can set up a VLAN

across two Switches using Tagged ports. This enables

ports that are members of the same VLAN (but are on

different switches) to communicate, provided that a

port on each Switch is set to Tagged, and that these

ports are connected.

Figure 32 Desktop VLAN Configuration

Endstations

in VLAN 1

Endstations

in VLAN 2

Port 1

Port 3

BaselBinaeseSlwinietcShw2i2tc5h02250 Plus

Port 26

Server

in VLAN 2

Server

in VLAN 1

If you want to add ports 1, 3, and 26 to VLAN2 (as

shown in Figure 32), so that the ports on the default

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Configuring VLANs

Figure 33 Tagged VLAN Configuration

4 Connect the Tagged port on Switch 1 (in this

example, port 16) to the Tagged port on Switch 2 (in

this example, port 8).

Those ports on Switch 1 that are members of VLAN2

can now communicate with those ports on Switch 2

that are members of VLAN2.

Spanning Tree

Spanning tree is a bridge-based system for providing

fault tolerance on networks and can be used to

detect and disable network loops. The spanning tree

ensures that the optimal path is maintained between

spanning tree-compliant networked devices by:

■ Disabling redundant paths when the main paths

are operational.

■ Enabling redundant paths if the main paths fail.

Spanning tree uses a distributed algorithm to select a

bridging device that serves as the root of the

To set up the configuration shown in Figure 33, do

the following:

spanning tree network. The bridging device, known

as the Root Bridge, generates bridge protocol data

units (BPDUs) on all ports at a regular interval known

as the Hello Time. All other spanning tree-compliant

devices on the network have a designated Root Port.

This is the Port nearest the Root Bridge and it is used

for receiving the BPDUs initiated by the Root Bridge. If

a bridge does not get a Hello BPDU after a

1 Create VLAN2 on both Switch 1 and Switch 2. You

need not create VLAN1 since it exists by default.

2 On Switch 1, set the ports that you want to be part of

VLAN2 to Untagged. Set one port (for example, port

16) to Tagged.

Click Apply.

predetermined interval, the bridge assumes that the

link to the Root Bridge is down. This bridge will then

initiate negotiations with other bridges to reconfigure

the network to reestablish a valid network topology.

3 On Switch 2, set the ports that you want to be part of

VLAN2 to Untagged. Set one port (for example, port

8) to Tagged.

Click Apply.

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CHAPTER 4: CONFIGURING THE SWITCH

After all the bridges on the network have determined

the configuration of their ports, each bridge only

forwards traffic between the Root Port and the ports

that are the Designated Bridge Ports for each network

segment. All other ports are blocked, which means

that they are prevented from forwarding traffic.

to receive the multicast service. This procedure is

called multicast filtering.

The purpose of IP multicast filtering is to optimize a

switched network’s performance, so multicast packets

will only be forwarded to those ports containing

multicast group hosts or multicast routers/switches,

instead of flooding traffic to all ports in the subnet

(VLAN).

To use spanning tree, choose enabled from the drop

State down menu, fill in the setup parameters, and

click Apply.

Choose enable or disable from the IGMP Snooping

Mode drop down menu.

Figure 34 Spanning Tree Screen

Figure 35 IGMP Snooping Setup Screen

IGMP Query

Choose enable or disable from the IGMP Query Mode

drop down menu.

Figure 36 IGMP Query Setup Screen

IGMP Snooping

This switch uses IGMP (Internet Group Management

Protocol) to query for any attached hosts that want to

receive a specific multicast service. It identifies the

ports containing hosts requesting to join the service

and sends data out to those ports only. It then

propagates the service request up to any neighboring

multicast switch/router to ensure that it will continue

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Configuring Port Settings

current connection status of each port or shut down

or disable ports.

Broadcast Storm

Use the Broadcast Storm page to set the Switch’s

broadcast storm control and threshold limits.

The Port menu includes five items:

■ Administration

A broadcast storm is an incorrect packet sent out on a

network that causes most hosts to respond all at

once, typically with wrong answers that start the

process over again. Broadcast storms use substantial

network bandwidth and may cause network

time-outs.

■ Link Aggregation

■ Spanning Tree per Port

■ Port Mirroring

■ Statistics

The settings include:

Administration

■ Status – Enables and disables broadcast storm

control.

Three tabs are available on the Port Administration

page:

■ Packet Rate Threshold – Sets the broadcast storm

threshold (64 to 1000000 kilobits per second).

■ Summary

■ Detail

Figure 37 Broadcast Storm Setup Screen

■ Setup

Summary

Use the Summary tab to display Port State, Flow

Control, Speed, Default VLAN ID, Link Type, or Duplex

for all the ports.

Configuring Port Settings

Using the Web interface, you can configure the

speed/duplex, flow control, link aggregation, and port

mirroring settings of each port. You can also view the

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CHAPTER 4: CONFIGURING THE SWITCH

Figure 38 Port Administration Summary Screen

Figure 39 Port Administration Detail Screen

Setup

Use the Setup tab to configure the port settings. The

following options are available:

■ Port State – Enables and disables the port.

■ Flow Control – Enables and disables flow control

for the entire Switch. When flow control is

enabled, the Switch regulates the packet flow so

that a sending device does not transmit more

packets than a receiving device can process. If flow

control is disabled, packets may be dropped under

certain periods of high traffic.

Detail

Use the Detail tab to display detailed port setting

information for a port.

Flow control is disabled by default.

■ Speed – Sets the speed mode of the port. Available

options include auto, 10, 100, and 1000. For 1000

Mbps connections, see “Speed/Duplex for 1000

Mbps Connections” below.

Auto (or autonegotiation) sets the optimum

combination of speed and duplex that can be

supported by both ends of the link.

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Configuring Port Settings

■ Duplex – Sets the duplex mode of the port.

CAUTION: Before manually setting a port to

Available options include auto, half, and full.

full-duplex, verify that the device connected to the

port is also manually set to the same speed and

duplex setting. If connecting link partners are left to

autonegotiate for a link manually set on this switch to

full-duplex, they will always negotiate to half-duplex,

resulting in a duplex mismatch. This can result in a

significant reduction in network performance. If you

are unsure of how to configure the speed/duplex

setting, simply enable autonegotiation for the port.

If you modify any of these settings, click Apply to save

your changes.

Figure 40 Port Administration Setup Screen

You cannot modify the speed/duplex settings of ports

that are members of a trunk or aggregated link.

Supported SFP transceivers only operate at

1000 Mbps full-duplex. Inserting an SFP transceiver

into a gigabit port disables the corresponding RJ-45

port, even if no fiber cable is inserted.

Link Aggregation

Link aggregation, also called “trunking”, refers to

bonding multiple ports into a single group to

effectively combine the bandwidth into a single

connection or a “trunk”. If you are connecting the

Switch to another switch or to an Internet backbone,

you can aggregate links on the Switch to increase

throughput and prevent packet loopback between

switches.

Speed/Duplex for 1000 Mbps Connections

You cannot preset the speed to 1000 Mbps. To run a

port at 1000 Mbps, you must enable autonegotiation

for the port. When autonegotiation is enabled, the

Switch will automatically connect at 1000 Mbps,

providing the connected device also supports this

speed.

For link aggregation to work, the trunks must be

configured on both ends (switches).

1000 Mbps connections are always full-duplex.

Half-duplex connections are only available for 10

Mbps and 100 Mbps settings.

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CHAPTER 4: CONFIGURING THE SWITCH

Figure 41 Link Aggregation Summary Screen

Guidelines for Creating Trunks

■ Any port on the Switch can be used for creating a

trunk.

■ This switch supports a maximum of four trunks.

■ Each trunk may contain up to four members.

■ A port may only be a member of one trunk at any

one time.

■ All ports in a trunk must be configured in an

identical manner, including communication mode

(that is, speed, duplex mode and flow control).

Create

Use the Create tab to add ports to a group

membership.

Four tabs are available on the Port Link Aggregation

page:

Figure 42 Link Aggregation Create Screen

■ Summary

■ Create

■ Modify

■ Remove

Summary

Use the Summary tab to display Group ID, Port

members, and Link Type for a list of link aggregate

groups.

To create a new link aggregation group:

1 Enter a link aggregation group ID in the box field.

2 Select the ports to add to the goup.

3 Click Apply.

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Configuring Port Settings

Figure 44 Link Aggregation Remove Screen

Modify

Use the Modify tab reassign port members to a link

aggregation group.

Figure 43 Link Aggregation Modify Screen

To remove a link aggregation group:

1 From the link aggregation group list, select the

aggregated group to remove.

2 Click Remove.

Spanning Tree per Port

This administrative tool supports the configuration of

the Switch to forward, or block and discard 802.1D

spanning tree BPDU packets.

To modify a link aggregation group:

1 Select the aggregation group to modify, then click

Select.

Spanning tree is a bridge-based system for providing

fault tolerance on networks and can be used to

detect and disable network loops. The spanning tree

ensures that the optimal path is maintained between

spanning tree-compliant networked devices by:

2 Select the ports to add to the goup.

3 Click Apply.

Remove

■ Disabling redundant paths when the main paths

are operational.

Use the Remove tab delete a link aggregation group.

■ Enabling redundant paths if the main paths fail.

Spanning tree uses a distributed algorithm to select a

bridging device that serves as the root of the

spanning tree network. The bridging device known as

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CHAPTER 4: CONFIGURING THE SWITCH

Figure 45 Spanning Tree Summary Screen

the Root Bridge generates BPDUs (Bridge Protocol

Data Units) on all ports at a regular interval known as

the Hello Time. All other spanning tree-compliant

devices on the network have a designated Root Port.

This is the Port nearest the Root Bridge and it is used

for receiving the BPDUs initiated by the Root Bridge. If

a bridge does not get a Hello BPDU after a

predetermined interval, the bridge assumes that the

link to the Root Bridge is down. This bridge will then

initiate negotiations with other bridges to reconfigure

the network to re-establish a valid network topology.

After all the bridges on the network have determined

the configuration of their ports, each bridge only

forwards traffic between the Root Port and the ports

that are the Designated Bridge Ports for each network

segment. All other ports are blocked, which means

that they are prevented from forwarding traffic.

Three tabs are available on the Spanning Tree per Port

page:

Detail

■ Summary

■ Detail

Use the Detail tab to display detailed spanning tree

information for a port.

■ Setup

Summary

Use the Summary tab to display Status, Edged Port,

Link Type, Path Cost, State, or Port Priority for all the

ports.

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Configuring Port Settings

Figure 46 Spanning Tree Detail Screen

device with the lowest MAC address will then

become the root device.

If you modify any of these settings, click Apply to save

your changes.

Figure 47 Spanning Tree Setup Screen

Setup

Use the Setup tab to configure the spanning tree

settings for each port. The following options are

available:

Port Mirroring

The Switch allows you to monitor traffic going in and

out of a particular port. For traffic monitoring to

work, you need to attach a network analyzer to one

port and use it to monitor the traffic of other ports in

the stack.

■ Status – Enables and disables spanning tree for the

port.

■ Edged Port – Enables and disables edged port for

the port.

To set up traffic monitoring, you need to set an

analysis port (the port that is connected to the

analyzer), and a monitor port (the port that is to be

monitored). Once the pair is defined, and you enable

traffic monitoring, the Switch takes all the traffic

going in and out of the monitor port and copies it to

the analysis port.

■ Link Type – Choose between Point-to-Point,

Shared, or Auto for the link type.

■ Path Cost – The path cost is used to determine the

best path between devices. The path cost method

is used to determine the range of values that can

be assigned to each interface.

■ Port Priority – Used in selecting the root device,

root port, and designated port. The device with

the highest priority becomes the STA root device.

However, if all devices have the same priority, the

CAUTION: The analyzer port should have a higher

bandwidth than the mirror port. Otherwise, the

Switch may not be able to copy all traffic effectively

during periods of high traffic.

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CHAPTER 4: CONFIGURING THE SWITCH

Figure 48 Port Mirroring Screen

QoS VoIP Traffic Settings

Using the Web interface, you can configure the Voice

over Internet Protocol (VoIP) settings.

The QoS VoIP Traffic Setting menu includes six tabs:

■ Summary

■ Setup

■ Port Setup

■ Port Detail

■ OUI Summary

■ OUI Modify

To set up port mirroring:

1 Connect a network analyzer to a port.

2 Access the Web interface. Click Port, then Port

Mirroring on the menu. The Port Monitoring Setup

Screen appears.

Summary

Use the Summary tab to display the global settings

for Voice VLAN.

3 Select the port number under Monitor Port to which

you want to monitor. Traffic to and from this port will

be forwarded to the analyser port.

Figure 49 QoS VoIP Summary Screen

4 Select the port number under Analyser Port to which

you connected the network analyzer. Traffic to and

from the selected mirrored ports will be forwarded to

this port.

5 Under Mirror Type, select to monitor incoming traffic,

outgoing traffic, or both.

6 Click Apply.

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QoS VoIP Traffic Settings

Setup

To configure the Voice VLAN settings for the ports:

Use the Setup tab to configure the global settings for

Voice VLAN. The following options are available:

1 Select Voice VLAN Mode and Security settings.

2 Select the ports you would like to apply these settings

■ Voice VLAN Status – Enable or disable Voice VLAN

to.

for the switch.

3 Click Apply.

■ Voice VLAN ID – Input the Voice VLAN ID for the

switch.

Figure 51 QoS Port Setup Screen

■ Voice VLAN Aging Time – Input the aging time.

You must first create a VLAN from the VLAN Setup

page before you can assign and configure a Voice

VLAN.

Figure 50 QoS VoIP Setup Screen

Port Detail

Use the Port Detail tab to display the Voice VLAN

information for selected ports.

Port Setup

Use the Port Setup tab to configure the port or trunk

setting for Voice VLAN. The following options are

available:

■ Voice VLAN Port Mode – Select between None,

Manual, or Auto.

■ Voice VLAN Port Security – Enable or disable the

security.

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CHAPTER 4: CONFIGURING THE SWITCH

Figure 52 QoS Port Detail Screen

OUI Modify

Use the OUI Modify tab to add to the list of

Organizational Unique Identifier. The following

options are available:

■ Telephony OUI – Input a new company identifier to

add to the list.

■ Description – Input a description for the new

company identifier.

To add to the OUI list:

1 Enter a Telephony OUI and description.

2 Click Add.

OUI Summary

Use the OUI Summary tab to display the list of

Organizational Unique Identifier for a company and

their description.

To remove an OUI from the list:

1 Select a Telephony OUI from the list.

2 Click Remove.

Figure 53 QoS OUI Summary Screen

Figure 54 QoS OUI Modify Screen

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Security

Figure 55 RADIUS Client Detail Screen

Security

Using the Web interface, you can configure the

RADIUS Client and 802.1X settings.

The Security menu includes two items:

■ RADIUS Client

■ 802.1X Settings

RADIUS Client

Remote Authentication Dial-in User Service (RADIUS)

is a logon authentication protocol that uses software

running on a central server to control access to

RADIUS-aware devices on the network. An

authentication server contains a database of multiple

user name/password pairs with associated privilege

levels for each user or group that require

Configure

Use the Configure tab to configure the RADIUS

settings. The following parameters are available:

management access to a switch.

■ Max Retries – Sets the number of retries of sending

The RADIUS Client menu includes two tabs:

authentication requests.

■ Timeout – Sets the interval between sending

■ Detail

authentication requests.

■ Configure

■ IP Address – The IP address of the RADIUS server.

Detail

■ UDP port – The RADIUS server UDP port used for

authentication messages.

Use the Detail tab to display the RADIUS Client

settings.

■ Key – Sets the RADIUS encryption key.

After you have filled in the parameters, click Apply to

save your changes.

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CHAPTER 4: CONFIGURING THE SWITCH

Figure 56 RADIUS Client Configure Screen

Figure 57 802.1X Summary Screen

802.1X Settings

The IEEE 802.1X (dot1x) standard defines a

Detail

Use the Detail tab to display detailed 802.1X

authentication information for a port.

port-based access control procedure that prevents

unauthorized access to a network by requiring users

to first submit credentials for authentication.

Figure 58 802.1X Detail Screen

The 802.1X settings menu includes three tabs:

■ Summary

■ Detail

■ Setup

Summary

Use the Summary tab to display the 802.1X

authentication settings.

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Security

Setup

■ Max Count – The maximum number of hosts that

can connect to a port when the Multi-Host

operation mode is selected. (Range: 1-1024;

Default: 5)

Use the Setup tab to configure the 802.1X

authenticaion settings. The following fields are

available:

■ Reauthentication Period – Sets the time period

after which a connected client must be

re-authenticated. (Range: 1-65535 seconds;

Default: 3600 seconds)

■ System Authentication – Sets the global setting for

802.1X. (Default: Disabled)

■ Operation Mode – Allows single or multiple hosts

(clients) to connect to an 802.1X-authorized port.

(Options: Single-Host, Multi-Host; Default:

Single-Host)

■ Quiet Period – Sets the time that a switch port

waits after the Max Request Count has been

exceeded before attempting to acquire a new

client. (Range: 1-65535 seconds; Default: 60

seconds)

■ Mode – Sets the authentication mode to one of

the following options:

■

Auto – Requires a dot1x-aware client to be

authorized by the authentication server. Clients

that are not dot1x-aware will be denied access.

■ Transmit Period – Sets the time period during an

authentication session that the switch waits before

re-transmitting an EAP packet. (Range: 1-65535;

Default: 30 seconds)

Force-Authorized – Forces the port to grant

access to all clients, either dot1x-aware or

otherwise.

After you have filled in the parameters, click Apply to

save your changes.

Force-Unauthorized – Forces the port to deny

access to all clients, either dot1x-aware or

otherwise.

Figure 59 802.1X Setup Screen

■ Maximum Request – Sets the maximum number of

times the switch port will retransmit an EAP

request packet to the client before it times out the

authentication session. (Range: 1-10; Default 2)

■ Mode Reauthentication – Sets the client to be

re-authenticated after the interval specified by the

Re-authentication Period. Re-authentication can be

used to detect if a new device is plugged into a

switch port. (Default: Disabled)

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CHAPTER 4: CONFIGURING THE SWITCH

Cable Diagnostics

The Switch provides cable diagnostic, which helps you

Monitoring

Using the Web interface, you can display address

detect and resolve issues with the attached cables.

The Cable Diagnostics menu includes two tabs:

■ Summary

table information and cable diagnostics.

The Monitoring menu includes two items:

■ Address Table

■ Diagnostics

■ Cable Diagnostics

Summary

Address Table

Use the Summary tab to display information on Test

Result, Cable Fault Distance, or Last Update for every

port on the switch.

Use the Address Table Summary screen to display the

Address Table information. You can query by selecting

a port, choosing a VLAN, or entering in a MAC

Address, then click Select.

Figure 61 Cable Diagnostic Summary Screen

Figure 60 Address Table Screen

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Monitoring

Diagnostics

Use the Diagnostics tab to display individual port

information on Test Result, Cable Fault Distance, and

Last Update.

Figure 62 Cable Diagnostic Screen

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CHAPTER 4: CONFIGURING THE SWITCH

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TROUBLESHOOTING

This chapter lists some issues that you may encounter

while installing, using, and managing the Switch,

with suggested courses of corrective action to take.

4 Reset the Switch either by:

■ Accessing the Web interface using Discovery, and

then pressing the RESET button on the Initialize tab

of the Administration menu. After you click RESET,

a confirmation message appears. Click OK to con-

firm.

If you encounter an issue that is not listed here and

you cannot solve it, check the 3Com Knowledgebase

at ^{http://knowledgebase.3com.com}before contacting

your local technical support representative.

■ Powering off the Switch, and then powering it

back on.

For more information on how to obtain support for

your Switch, refer to Appendix A.

The Switch will perform automatic IP configuration

after you reset it. See “Automatic IP Configuration”

on page 29 for more information.

Resetting to Factory Defaults

If the Switch does not operate normally or if the

firmware becomes corrupted, you can reset the

Switch to factory defaults.

Forgotten Password

If you forget the password to the Web interface after

you set it, you will need to reset the Switch to regain

access. See “Resetting to Factory Defaults” on

page 59 for instructions.

CAUTION: Resetting the Switch to factory defaults

erases all your settings. You will need to reconfigure

the Switch after you reset it.

After resetting the Switch, log on to the Web inter-

face using the default admin account settings:

To reset the Switch to its factory defaults:

1 Using the tip of a pen (or a similar object), press the

Recovery button on the rear panel of the Switch. See

Figure 1 for illustration.

■ User name – admin

■ Password – blank (no password)

2 Power off the Switch, and then power it back on,

while keeping the Recovery button pressed.

3 Release the Recovery button.

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CHAPTER 5: TROUBLESHOOTING

■ The correct category of cable is being used for the

required link speed. Category 3 cables can be used

for 10BASE-T operation only. Category 5 cable is

required for 100BASE-TX or 1000BASE-T. 3Com

recommends Category 5e or 6 cables for

1000BASE-T operation.

Forgotten Static IP Address

If you forget the static IP address that you assigned to

the Switch and you need to access the Web interface,

use the Discovery application to automatically detect

the IP address and connect to the interface.

For information on using the Discovery application,

refer to “Running the Discovery Application” on

page 21.

A fiber cable is connected, but the Module

Active LED is off.

Verify that:

■ The fiber cable is in good condition.

■ The SFP module is correctly inserted.

Solving LED Issues

This section lists some issues that are related to the

LEDs on the front panel of the Switch. For

information on basic LED checks, refer to the

following topics in Chapter 1:

■ A 3Com SFP module is being used. Refer to

“Approved SFP Transceivers” on page 18 for

details.

■ The equipment at the far end is installed and cor-

■ (4) Module Active LEDs

■ (3) Link/Activity LEDs

■ (5) Power LED

rectly configured.

The Link/Activity LED is on, but network perfor-

mance is poor

A link is connected, but the Link/Activity LED for

the port is off.

The Switch supports full-duplex autonegotiation. If

the connected device does not support

autonegotiation, ensure that it is configured for

half-duplex operation only. If the connected device

has autonegotiation disabled or overridden, and is

configured as full-duplex, the Switch will configure

the link as half-duplex, causing a mismatch that will

reduce network performance when data is

transmitting and receiving simultaneously on the

same link.

There is a problem with this connection. Verify that:

■ The device being connected to is powered on and

operating correctly.

■ The cable is connected at both ends.

■ The cable is not damaged.

■ If the connection is to a workstation, that the

workstation's network interface is installed and

configured correctly.

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If the Problem Persists

Ensure that the connected device has either:

■ Autonegotiation enabled, or

If the Problem Persists

If the problem persists and the unit still does not

operate successfully, contact your 3Com network

supplier with the following information before

returning the unit:

■ The ports are configured for half-duplex operation

All ports appear to show continual activity.

There may be broadcast storms on the network.

Remove port connections one at a time, waiting a

few seconds between each port. If the LEDs go off

after removing a port connection, the device that was

connected to that port is introducing an excessive

amount of broadcast frames to the network. Some

pieces of network equipment operate by sending out

broadcast frames regularly.

■ Product number and serial number (printed on a

label supplied with the unit).

■ A brief description of the issue

Refer to the documentation that accompanies the

device for information on disabling the broadcast

operation.

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CHAPTER 5: TROUBLESHOOTING

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OBTAINING SUPPORT FOR YOUR PRODUCT

networking projects. More information on 3Com

maintenance and Professional Services is available at

http://www.3com.com/

Warranty and other service benefits start from the

date of purchase, so it is important to register your

product quickly to ensure you get full use of the

warranty and other service benefits available to you.

Contact your authorized 3Com reseller or 3Com for a

complete list of the value-added services available in

your area.

Warranty and other service benefits are enabled

through product registration. Register your product at

http://eSupport.3com.com/. 3Com eSupport

services are based on accounts that you create or

have authorization to access. First time users must

apply for a user name and password that provides

access to a number of eSupport features including

Product Registration, Repair Services, and Service

Request. If you have trouble registering your product,

please contact 3Com Global Services for assistance.

Troubleshoot Online

You will find support tools posted on the 3Com web

site at http://www.3com.com/

3Com Knowledgebase helps you troubleshoot

3Com products. This query-based interactive tool is

located at http://knowledgebase.3com.com and

contains thousands of technical solutions written by

3Com support engineers.

Purchase Value-Added Services

To enhance response times or extend warranty

benefits, contact 3Com or your authorized 3Com

reseller. Value-added services like 3Com Express^SM

and Guardian^SMcan include 24x7 telephone technical

support, software upgrades, onsite assistance or

advance hardware replacement. Experienced

engineers are available to manage your installation

with minimal disruption to your network. Expert

assessment and implementation services are offered

to fill resource gaps and ensure the success of your

Access Software Downloads

Software Updates are the bug fix / maintenance

releases for the version of software initially purchased

with the product. In order to access these Software

Updates you must first register your product on the

3Com web site at http://eSupport.3com.com/.

First time users will need to apply for a user name and

password. A link to software downloads can be found

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APPENDIX A: OBTAINING SUPPORT FOR YOUR PRODUCT

at http://eSupport.3com.com/, or under the

Product Support heading at http://www.3com.com/

To send a product directly to 3Com for repair, you

must first obtain a return authorization number

(RMA). Products sent to 3Com, without authorization

numbers clearly marked on the outside of the pack-

age, will be returned to the sender unopened, at the

sender’s expense. If your product is registered and

under warranty, you can obtain an RMA number

online at http://eSupport.3com.com/. First time

users will need to apply for a user name and pass-

word.

Software Upgrades are the software releases that

follow the software version included with your origi-

nal product. In order to access upgrades and related

documentation you must first purchase a service con-

tract from 3Com or your reseller.

Telephone Technical Support and Repair

To obtain telephone support as part of your warranty

and other service benefits, you must first register your

product at http://eSupport.3com.com/

3Com offers telephone, e-mail and internet access to

technical support and repair services. To access these

services for your region, use the appropriate

telephone number, URL or e-mail address from the list

below.

Warranty and other service benefits start from the

date of purchase, so it is important to register your

product quickly to ensure you get full use of the war-

ranty and other service benefits available to you.

Telephone numbers are correct at the time of publica-

tion. Find a current directory of support telephone

numbers posted on the 3Com web site at

When you contact 3Com for assistance, please have

the following information ready:

http://csoweb4.3com.com/contactus/

■ Product model name, part number, and serial

number

■ Proof of purchase, if you have not pre-registered

your product

■ A list of system hardware and software, including

revision level

■ Diagnostic error messages

■ Details about recent configuration changes, if

applicable

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Country

Telephone Number

Austria

01 7956 7124

070 700 770

7010 7289

Country

Telephone Number

Belgium

Denmark

Finland

Asia, Pacific Rim Telephone Technical Support and

Repair

01080 2783

France

0825 809 622

01805 404 747

06800 12813

1407 3387

1800 945 3794

199 161346

342 0808128

0900 777 7737

815 33 047

00800 441 1357

707 200 123

0800 995 014

9 021 60455

07711 14453

08488 50112

0870 909 3266

Australia

Hong Kong

India

1 800 678 515

800 933 486

+61 2 9424 5179 or

000800 6501111

001 803 61 009

00531 616 439 or

03 3507 5984

1800 801 777

0800 446 398

+61 2 9937 5083

1235 61 266 2602 or

1800 1 888 9469

800 810 3033

Germany

Hungary

Ireland

Israel

Italy

Luxembourg

Netherlands

Norway

Poland

Portugal

South Africa

Spain

Sweden

Switzerland

U.K.

Indonesia

Japan

Malaysia

New Zealand

Pakistan

Philippines

P.R. of China

Singapore

S. Korea

Taiwan

Thailand

800 6161 463

080 333 3308

00801 611 261

001 800 611 2000

You can also obtain support in this region using the following

URL: http://emea.3com.com/support/email.html

You can also obtain support in this region using the following

e-mail: [email protected]

Country

Telephone Number

Or request a repair authorization number (RMA) by fax using

this number: +65 543 6348

Latin America Telephone Technical Support and

Repair

Europe, Middle East, and Africa Telephone Technical

Support and Repair

From the Caribbean, Central and South America, call:

From anywhere in these

regions, call:

+44 (0)1442 435529

From the following countries, you may use the numbers

shown:

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APPENDIX A: OBTAINING SUPPORT FOR YOUR PRODUCT

Country

Telephone Number

Country

Telephone Number

Antigua

Argentina

Aruba

Bahamas

Barbados

Belize

Bermuda

Bonaire

1 800 988 2112

0 810 444 3COM

1 800 998 2112

52 5 201 0010

1 800 998 2112

0800 13 3COM

You can also obtain support in this region using the follow-

ing:

Spanish speakers, enter the URL:

http://lat.3com.com/lat/support/form.html

Portuguese speakers, enter the URL:

http://lat.3com.com/br/support/form.html

English speakers in Latin America should send e-mail to:

[email protected]

Brazil

Cayman

1 800 998 2112

Chile

AT&T +800 998 2112

1 800 998 2112

US and Canada Telephone Technical Support and Repair

Colombia

Costa Rica

Curacao

1 800 876 3266

Ecuador

AT&T +800 998 2112

57 1 657 0888

Dominican Republic

Guatemala

Haiti

Honduras

Jamaica

Martinique

Mexico

Nicaragua

Panama

Paraguay

Peru

Puerto Rico

Salvador

Trinidad and Tobago

Uruguay

Venezuela

Virgin Islands

AT&T +800 998 2112

1 800 998 2112

571 657 0888

01 800 849CARE

AT&T +800 998 2112

54 11 4894 1888

AT&T +800 998 2112

1 800 998 2112

AT&T +800 998 2112

1 800 998 2112

AT&T +800 998 2112

57 1 657 0888

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SAFETY INFORMATION

Important Safety Information

You can find the 3Com Switch Family Safety and

Regulatory Information manual on the product

CD-ROM that was included with your switch. You can

also download the safety manual from the 3Com

Web site: www.3Com.com

Please refer to the safety information found in the

3Com Switch Family Safety and Regulatory Informa-

tion manual included with this product.

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APPENDIX B: SAFETY INFORMATION

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TECHNICAL INFORMATION

Physical

Related Standards

Width

440 mm (17.3 in.)

215 mm (8.5 in.)

41 mm (1.6 in.) or 1U

3.1 kgs (6.83 lbs)

The 3Com Baseline Switch 2250 Plus has been

designed to the following standards:

Depth

Height

Functional

ISO 8802-3, IEEE 802.3 (Ethernet),

Weight

Mounting

IEEE 802.3u (Fast Ethernet), IEEE

802.3ab (Gigabit Ethernet), IEEE

802.3x (Flow Control), IEEE 802.1D

(Bridging)

Free standing, or 19 in. rack

mounted using the mounting kit

supplied

MAC Address

Safety

4096

UL/CUL (UL60950-1, CSA22.2 No

60950-1), TUV/GS (EN60950-1),

IEC60950-1

Electrical

Power Inlet

IEC 320

AC Line Frequency

Input Voltage

Current Rating

50/60 Hz

EMC Emissions

Immunity

EN 55022 Class A, FCC Part 15

Subpart B Class A, ICES-003 Class

A, VCCI Class A, AS/NZS 3548

Class A, CNS 13438 Class A

100–240 VAC

2 amperes (maximum)

Maximum Power Con- 56 watts

sumption

EN 55024

184.3 BTU/hr

Maximum Power Dissi-

pation

Environmental

Operating Temperature 0–40 °C (32–104 °F)

Humidity

Standard

0–95% (non-condensing)

EN 60068 (IEC 68)—various parts

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APPENDIX C: TECHNICAL INFORMATION

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GLOSSARY

10BASE-T

the IEEE 802.3 standard for Ethernet and is an

operation that takes place in a few milliseconds.

Autonegotiation must be enabled for the

1000BASE-T ports to operate at 1000 Mbps,

full-duplex.

The IEEE specification for 10 Mbps Ethernet over

Category 3, 4 or 5 twisted pair cable.

100BASE-TX

The IEEE specification for 100 Mbps Fast Ethernet

over Category 5 twisted-pair cable.

bandwidth

The information capacity (measured in bits per

second) that a channel can transmit. The bandwidth

of Ethernet is 10 Mbps, the bandwidth of Fast

Ethernet is 100 Mbps and Gigabit Ethernet is 1000

Mbps.

1000BASE-LX

IEEE 802.3z specification for Gigabit Ethernet over

9/125 micron core single-mode fiber cable.

1000BASE-SX

category 3 cable

IEEE 802.3z specification for Gigabit Ethernet over

two strands of 50/125 or 62.5/125 micron core

multimode fiber cable.

One of five grades of Twisted Pair (TP) cabling defined

by the EIA/TIA-568 standard. Category 3 is voice

grade cable and can only be used in Ethernet

networks (10BASE-T) to transmit data at speeds of up

to 10 Mbps.

1000BASE-T

IEEE 802.3ab specification for Gigabit Ethernet over

100-ohm Category 5, 5e or 6 twisted-pair cable

(using all four wire pairs).

category 5 cable

One of five grades of Twisted Pair (TP) cabling defined

by the EIA/TIA-568 standard. Category 5 can be used

in Ethernet (10BASE-T) and Fast Ethernet networks

(100BASE-TX) and can transmit data at speeds of up

to 100 Mbps. Category 5 cabling is better to use for

network cabling than Category 3, because it supports

both Ethernet (10 Mbps) and Fast Ethernet (100

Mbps) speeds.

autonegotiation

Autonegotiation is where two devices sharing a link,

automatically configure to use the best common

speed. The order of preference (best first) is:

1000BASE-T full-duplex, 100BASE-TX full-duplex,

100BASE-TX half-duplex, 10BASE-T full-duplex, and

10BASE-T half-duplex. Autonegotiation is defined in

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GLOSSARY

category 5e cables

One of five grades of Twisted Pair (TP) cabling defined

Ethernet address

See MAC address.

by the EIA/TIA-568 standard. Category 5e can be

used in Ethernet (10BASE-T), Fast Ethernet

(100BASE-TX) and Gigabit Ethernet (1000BASE-T)

networks, and can transmit data at speeds of up to

1000 Mbps.

Fast Ethernet

An Ethernet system that is designed to operate at 100

Mbps.

Gigabit Ethernet

category 6 cable

An Ethernet system that is designed to operate at

1000 Mbps.

One of five grades of Twisted Pair (TP) cabling defined

by the EIA/TIA-568-B standard. Category 6 can be

used in Ethernet (10BASE-T), Fast Ethernet

(100BASE-TX) and Gigabit Ethernet (1000BASE-T)

networks, and can transmit data at speeds of up to

1000 Mbps.

full-duplex

A system that allows packets to be transmitted and

received at the same time and, in effect, doubles the

potential throughput of a link.

client

DHCP

half-duplex

The term used to describe the desktop PC that is

connected to your network.

A system that allows packets to be transmitted and

received, but not at the same time. Half-duplex is not

supported for 1000 Mbps. Contrast with full-duplex.

Dynamic Host Configuration Protocol. This protocol

automatically assigns an IP address for every

computer on your network. Windows 95, Windows

98 and Windows NT 4.0 contain software that

assigns IP addresses to workstations on a network.

These assignments are made by the DHCP server

software that runs on Windows NT Server.

IEEE

Institute of Electrical and Electronics Engineers. This

American organization was founded in 1963 and sets

standards for computers and communications.

IEEE 802.1D

Specifies a general method for the operation of MAC

bridges, including the Spanning Tree Protocol.

Ethernet

A LAN specification developed jointly by Xerox, Intel

IEEE 802.1Q

and Digital Equipment Corporation. Ethernet

networks use CSMA/CD to transmit packets at a rate

of 10 Mbps and 100 Mbps over a variety of cables.

VLAN Tagging - Defines Ethernet frame tags that

carry VLAN information. It allows switches to assign

endstations to different virtual LANs, and defines a

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GLOSSARY

standard way for VLANs to communicate across

switched networks.

IP Address

Internet Protocol Address. A unique identifier for a

device attached to a network using TCP/IP. The

address is written as four octets separated with

periods (full-stops), and is made up of a network

section, an optional subnet section and a host

section.

IEEE 802.1p

An IEEE standard for providing quality of service (QoS)

in Ethernet networks. The standard uses packet tags

that define up to eight traffic classes and allows

switches to transmit packets based on the tagged

priority value.

LAN

Local Area Network. A network of end stations (such

as PCs, printers, servers) and network devices (hubs

and switches) that cover a relatively small geographic

area (usually not larger than a floor or building). LANs

are characterized by high transmission speeds over

short distances (up to 1000 meters).

IEEE 802.3ad

A standard that defines link aggregation. 802.3ad is

now incorporated into the relevant sections of the

IEEE Std. 802.3-2002.

IETF

Layer 2

Internet Engineering Task Force. An organization

responsible for providing engineering solutions for

TCP/IP networks. In the network management area,

this group is responsible for the development of the

SNMP protocol.

Data Link layer in the ISO 7-Layer Data

Communications Protocol. This is related directly to

the hardware interface for the network devices and

passes on traffic based on MAC addresses.

link aggregation

Internet Protocol. IP is a layer 3 network protocol that

is the standard for sending data through a network.

IP is part of the TCP/IP set of protocols that describe

the routing of packets to addressed devices. An IP

address consists of 32 bits divided into two or three

fields: a network number and a host number or a

network number, a subnet number, and a host

number.

See Trunking.

MAC

Media Access Control. A protocol specified by the

IEEE for determining which devices have access to a

network at any one time.

MAC address

Media Access Control Address. Also called the

hardware, physical, or Ethernet address. A layer 2

address associated with a particular network device.

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GLOSSARY

Most devices that connect to a LAN have a MAC

address assigned to them as they are used to identify

other devices on a network. MAC addresses are 6

bytes long.

SFP

Small Form Factor Pluggable (SFP) Connectors are

based on an open standard that enables hot

swapping of various types of fiber optic and

copper-based transceivers into the host equipment.

network

A network is a collection of computers and other

subnet address

An extension of the IP addressing scheme that allows

computer equipment that are connected for the

purpose of exchanging information or sharing

resources. Networks vary in size, some are within a

single room, others span continents.

a site to use a single IP network address for multiple

physical networks.

subnet mask

ping

A subnet mask, which may be a part of the TCP/IP

information provided by your ISP, is a set of four

numbers configured like an IP address. It is used to

create IP address numbers used only within a

particular network (as opposed to valid IP address

numbers recognized by the Internet, which must

assigned by InterNIC).

Packet Internet Groper. An internet utility used to

determine whether a particular IP address is online. It

is used to test and debug a network by sending out a

packet and waiting for a response.

protocol

A set of rules for communication between devices on

a network. The rules dictate format, timing,

sequencing and error control.

subnet

switch

A network that is a component of a larger network.

RJ-45

A standard connector used to connect Ethernet

networks. The “RJ” stands for “registered jack.”

A device that interconnects several LANs to form a

single logical LAN that comprises of several LAN

segments. Switches are similar to bridges, in that they

connect LANs of a different type; however they

connect more LANs than a bridge and are generally

more sophisticated.

server

A computer on a network that is shared by multiple

end stations. Servers provide end stations with access

to shared network services such as computer files and

printer queues.

TCP/IP

Transmission Control Protocol/Internet Protocol. This

is the name for two of the most well-known protocols

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GLOSSARY

developed for the interconnection of networks.

Originally a UNIX standard, TCP/IP is now supported

on almost all platforms, and is the protocol of the

Internet.

TCP relates to the content of the data travelling

through a network — ensuring that the information

sent arrives in one piece when it reaches its

destination. IP relates to the address of the end

station to which data is being sent, as well as the

address of the destination network.

traffic monitoring

Enables the monitoring of port traffic by attaching a

network analyzer to one switch port, in order to

monitor the traffic of other ports on the Switch.

trunking

A method which specifies how to create a single

high-speed logical link that combines several

lower-speed physical links.

VLAN

Virtual LAN. A collection of network nodes that share

the same collision domain regardless of their physical

location or connection point in the network. A VLAN

serves as a logical workgroup with no physical

barriers, and allows users to share information and

resources as though located on the same LAN.

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GLOSSARY

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INDEX

Numbers

1000BASE-LX 71

1000BASE-SX 71

1000BASE-T 71

100BASE-TX 71

10BASE-T 71

Ethernet 72

LAN defined 73

LED issues 60

LEDs

Link/Activity 10

Module Active 11

Power 12

Fast Ethernet 72

forgotten IP address 59

forgotten password 59

free-standing 14

front panel

link aggregation 45

local area network 73

auto IP configuration 29

default IP address 29

default mask 29

Link/Activity LEDs 10

Module Active LEDs 11

Power LED 12

RJ-45 ports 11

self-adhesive pads 12

SFP ports 10

autonegotiation

autosensing

MAC address 73

media access control 73

monitoring traffic 49

mounting kit

full-duplex 72

contents 13

using 14

bandwidth 71

Gigabit Ethernet 72

network analyzer 49

network cables

category 3 71

category 5 71

category 5e 72

category 6 72

network defined 74

client 72

configuration

overview 27

connecting

half-duplex 72

network device 17

SFP transceivers 18

conventions

notice icons, About This Guide

text, About This Guide

IEEE 72

IETF 73

installing 13

IP address

auto configuration 29

modifying 29

IP defined 73

package contents 12

panels

front

rear 12

DHCP 72

Discovery 21

dynamic host control protocol See DHCP

password

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INDEX

changing 32, 34

default (blank) 32

setting 28

troubleshooting 59

forgotten IP address 59

forgotten password 59

LED-related issues 60

POST failed 17

physical features

port settings

configuring 43, 50, 53

ports

trunking See link aggregation

RJ-45 11

SFP 8, 10

positioning 13

POST 16

powering on 16

power-on self-test See POST

protocol defined 74

user name

default 32

viewing

status information 27

VLANs 35

creating 41

maximum supported 35

sample configurations 40

rack-mounting 14

rear panel

power supply 12

Recovery button 12

resetting to factory defaults 59

RJ-45

defined 74

ports 11

Web interface

accessing directly 26

accessing using Discovery 21

buttons 25

connecting 21

logging on 23

menu 23

server defined 74

SFP ports 8, 10

SFP transceivers 18

approved (supported) 18

inserting 18

navigating 23

requirements for accessing 21

removing 19

spot checks 19

subnet mask 74

switch defined 74

TCP/IP 73

defined 74

traffic 75

monitoring 49

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REGULATORY NOTICES

FCC STATEMENT

VCCI STATEMENT

This equipment has been tested and found to comply with the limits for a Class A digital

device, pursuant to part 15 of the FCC rules. These limits are designed to provide

reasonable protection against harmful interference when the equipment is operated in

a commercial environment. This equipment generates, uses and can radiate radio

frequency energy and, if not installed and used in accordance with the instructions, may

cause harmful interference to radio communications. Operation of this equipment in a

residential area is likely to cause harmful interference to radio communications, in which

case the user will be required to correct the interference at their own expense.

INFORMATION TO THE USER

If this equipment does cause interference to radio or television reception, which can be

determined by turning the equipment off and on, the user is encouraged to try to

correct the interference by one or more of the following measures:

■

Reorient the receiving antenna.

Relocate the equipment with respect to the receiver.

Move the equipment away from the receiver.

Plug the equipment into a different outlet so that equipment and receiver are on

different branch circuits.

If necessary, the user should consult the dealer or an experienced radio/television

technician for additional suggestions. The user may find the following booklet prepared

by the Federal Communications Commission helpful:

How to Identify and Resolve Radio-TV Interference Problems

This booklet is available from the U.S. Government Printing Office, Washington,

DC 20402, Stock No. 004-000-00345-4.

In order to meet FCC emissions limits, this equipment must be used only with cables

which comply with IEEE 802.3.

CE STATEMENT (EUROPE)

This product complies with the European Low Voltage Directive 73/23/EEC and EMC

Directive 89/336/EEC as amended by European Directive 93/68/EEC/.

CSA STATEMENT

This Class A digital apparatus meets all requirements of the Canadian

Interference-Causing Equipment Regulations.

Cet appareil numérique de la classe A respecte toutes les exigences du Règlement sur le

matériel brouilleur du Canada.

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