Accton Technology 1500 User Manual

EtherHub 1500 System

User’s Guide

✚

♦ EtherHub-16i

✚

♦ EtherHub-16mi

EtherHub 1500 System

User’s Guide

✚

♦ EtherHub-16i

✚

♦ EtherHub-16mi

Copyright (c) 1995 by Accton Technology Corporation. All rights reserved.

No part of this document may be copied or reproduced in any form or by any means without the prior written
consent of Accton Technology Corporation.

Accton makes no warranties with respect to this documentation and disclaims any implied warranties of
merchantability, quality, or fitness for any particular purpose. The information in this document is subject to change
without notice. Accton reserves the right to make revisions to this publication without obligation to notify any person
or entity of any such changes.

.QWHUQDWLRQDO-HDGTXDUWHUV

No. 1 Creation Road III,
Science-based Industrial Park
Hsinchu 300, Taiwan, R.O.C.
Phone: [phone]
FAX: [phone]
BBS: 886-35-770-654
Internet: [e-mail]

:8&-HDGTXDUWHUV

1962 Zanker Road
San Jose, CA 95112
Phone: [phone]
FAX: [phone]
BBS: 408-452-8828
FAST FAX: [phone]

Accton, AccView, EtherHub and SwitcHub are trademarks or registered trademarks of Accton Technology
Corporation. Other trademarks or brand names mentioned herein are trademarks or registered trademarks of their
respective companies.

EH1501s
EH1502s
E0895-R01
150482-101

FCC Warning

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 instruction
manual may cause harmful interference to radio communications. Its
operation in a residential area is likely to cause harmful interference in
which case the user will be required to correct the interference at his
own expense.

A shielded transceiver cable is required to be used in order to ensure
compliance with FCC Part 15; it is the responsibility of the user to
provide such cable.

Changes or modifications not expressly approved by the party responsible
for compliance could void the user’s authority to operate the equipment.

Canadian Standards Association (CSA) Statement

This digital apparatus does not exceed the Class A limits for
radio noise emissions from digital apparatus as set out in the
radio interference regulations of the Canadian Department of
Communciations.

FCC Warning i

Sicherheitshinweise

1. Die Steckdose muß sich in der Nähe des Gerätes befinden und leicht
änglich sein.

zug

2. Zum Reinigen den Stecker aus der Steckdose ziehen. Beim Reinigen

keine Fl
angefeuchtetes Tuch.

3. Das ...... ger

benutzen, wie z.B. Badezimmer, Schwimmbad, Sp
Eindringen von Wasser kann zur Zerst

4. Das ...... ger

Rollwagen, Gestell usw., aufstellen. Es k
Verletzungen oder Besch
verursachen.

5. Die Bel

fl
Zerst

6. Versuchen Sie niemals dieses Ger

oder Abnehmen des Geh
besteht.

7. Keine Gegenst

durch scharfe Kanten zerst

8. Keinerlei Gegenst

dadurch sonst zu Kurzschl

9. Bei St

10. Bei Reperaturen d
gleichen Eigenschaften verwendet werden. Andere Bauteile k
Feuer, elektrischen Schlag oder andere Gefahren verursachen.

11. Nach Beendigung von Wartungsarbeiten oder Reperaturen durch den
Kundendienst sollte die Sicherheitspr

12. Bei l
spannung zu trennen. Dies verhindert eine Besch
durch eine

Der arbeitsplatzbezogene L

üssigreiniger oder Sprays verwenden, sondern ein

ät nicht in Naßräume oder in der Nähe von Wasser

ülbecken usw. . Das

örung des Gerätes führen.

ät nicht auf einer unstabilen Unterlage, wie z.B.

önnte herunterfallen und

ädigungen von Mensch und Gerät

üftungsöffnungen nicht blockieren oder auf falscher Ober-

äche, wie Bett, Sofa usw., stellen. Durch die Blockierung kann es zur

örung des Gerätes durch Überhitzung kommen.

ät selbst zu warten, da beim Öffnen

äuses die Gefahr eines elektrischen Schlages

ände auf das Anschlußkabel stellen, damit es nicht

ört werden kann.

ände durch die Öffungen in das Gerät stecken, da es

üssen kommen kann.

örungen des Gerätes den Wartungsdienst verständigen.

ürfen nur Orginalersatzteile oder Bauteile mit

önnen

üfung durchgeführt werden.

ängerem Stillstand des Gerätes, ist diese von der Versorgungs-

ädigung des Gerätes

Überspannung in der Zuleitung.

ärmschutzpegel nach DIN 45 635 ist kleiner

70dB (A).

Sicherheitshinweise iii

About this Guide

This is an installation guide for the EtherHub 1500 hubs 
EtherHub-16i
topics:

+

and EtherHub-16mi+. It covers the following

ì Product description, summary of important features and

specifications

ì Brief description of the EtherHub 1500 System
ì Description of significant components of the unit including

LED indicators, ports, buttons and switches

ì Hardware installation procedure
ì System setup and configuration
ì Applications

v

Package Checklist

Package Contents

Carefully unpack the contents of the package and verify them
against the checklist given below. This checklist applies to both
the EtherHub-16i

æ EtherHub-16i

EtherHub-16mi

æ One AC power cord
æ 0.5 meter FlexBus 1500 cable
æ Four rubber feet
æ BNC T-type connector and two 50-ohm (Ω) terminators

(for models with the BNC transceiver module only)

+

and EtherHub-16mi+ unless otherwise specified.

+

(Model No. EH1501s) or

+

(Model No. EH1502s)

In addition, the EtherHub-16mi

æ One serial RS232 connector module which includes 2 DB9

+

package includes the following:

to RJ-45 converter connectors, one DB25 to RJ-45 converter
connector, and one 3-meter parallel UTP cable

æ Diskette containing -

Accton’s EtherHub 1500 System Configuration Program

Please inform your dealer immediately should there be any
wrong, missing, or damaged parts.

If possible, retain the carton, including the original packing
materials. Use them again to repack the unit in case there is a
need to return it for repair.

To qualify for product updates and product warranty
registration, fill in the

Owner Registration Card and return it

to Accton Technology Corporation.

vii

Contents

Chapter 1: Overview 1-1

The EtherHub 1500 System 1-1
Features of EtherHub 1500 System 1-4
Distinguishing Factors of EtherHub 1500 System 1-5

Chapter 2: Hardware Description 2-1

Front Panel Displays 2-1

SmartWatch LED Panel 2-2

PWR/CPU 2-3
Interhub 2-3
Isolated (EtherHub-16i
Serial (EtherHub-16mi
Terminator 2-4
Monitor (EtherHub-16i
SNMP (EtherHub-16mi
Jabber 2-6
Alert 2-7
Utilization 2-7
Collision 2-8
Segment LED Indicators 2-9
Hub ID Indicators 2-10
Port Status Indicators 2-10
PARTITION/DISABLE 2-11
LINK/TRAFFIC 2-12

Diagnostic Test LED Indicators 2-13
Configure Button 2-14
STP Station Ports 2-15
Daisy-Chain Switch 2-15

Rear Panel Displays 2-16

Port Connections 2-16

FlexBus 1500™ 2-16

Serial Port (EtherHub-16mi

ALT Port 2-17

BNC Module (10BASE2) 2-18
Power Socket 2-18
Power Switch 2-18

+

only) 2-3

+

only) 2-4

+

only) 2-5

+

only) 2-5

+

only) 2-17

ix

EtherHub 1500 System User’s Guide

Chapter 3: Hardware Installation 3-1

Before You Begin 3-1
Hardware Installation 3-2

Stacking Hubs without a Rack 3-3
Mounting Hubs on a Rack 3-4
Connecting the Hub System 3-5
Preparing for System Configuration 3-7

Local Out-of-Band Configuration 3-7

Remote Out-of-Band Configuration 3-8

In-Band Configuration 3-10
Installing an SNMP Backup Agent 3-10

Chapter 4: Setup and Configuration 4-1

System Setup 4-1

Diagnostic Tests 4-1

Upon Power On 4-1

During Normal Operation 4-2
Multi-Segment Architecture 4-2
FlexBus 1500 Management Link 4-3
Hub ID Setting 4-3
SNMP Backup Agent 4-3
Port Backup Function 4-4
Hot Remove Function 4-5
Preparing for Configuration Management 4-5

Out-of-Band Configuration 4-5

EtherHub 1500 System C onf igu ration Program (Et herHu b-16m i

System Menu 4-9

Displaying System Information 4-9

Changing System Configuration 4-10

Assigning Trap Managers 4-10

Downloading System Software 4-11

Restarting the Agent 4-11

Reverting Configuration to Factory Settings 4-11
Control Menu 4-12

Configuring Hub Parameters 4-12

Configuring Port Parameters 4-13

Defining Backup Ports 4-13

Setting the External Configure Buttons 4-14

+

) 4-8

x Contents

EtherHub 1500 System User’s Guide

Performance Menu 4-14
Threshold Menu 4-14

Using the Configure Button 4-16

Selections Available 4-18

Chapter 5: Applications 5-1

Attaching Stack to One Segment 5-1
Attaching Stack to Three Segments 5-2
Attaching Stack to Multiple Segments 5-3
Each Hub is Isolated 5-4
Extending the Network with STP/BNC Connections 5-5
Linking a Stack to a Network Management Station 5-6
Interconnecting Segments 5-7
Linking a Distributed Segment 5-8
Linking Distributed Segments 5-9
Operating in Novell NetWare IPX Environment 5-10
Operating in TCP/IP Environment 5-11

Contents xi

EtherHub 1500 System User’s Guide

Appendix A: Product Specifications A-1

Features A-1
Physical Characteristics A-1
Specifications for FlexBus 1500 Cable A-2

Attenuation for Horzontal FlexBus 1500 Cable

Error! Bookmark not defined.

NEXT for Horizontal FlexBus 1500 Cable A-3

Standards Compliance A-4

Appendix B: Pin Assignments B-1

FlexBus 1500 Pin Description B-1
RS232 Port Pin Description B-1
DB9 Serial Port to RJ-45 Converter Connector Pin Assignment B-2
DB9 PC’s COM Port to RJ-45 Converter Pin Assignment B-2
DB25 RS232 to RJ-45 Converter Connector Pin Assignment B-3
Connection from EH1502s Serial Port to PC’s COM Port B-3
Connection from EH1502s S eri al Port t o Modem’s DCE Port B-4

Appendix C: Product Support Services C-1

Product Registration C-1
Problem Report C-1
Hardware Repair Service C-1
Software Update and Upgrade Service C-2
Bulletin Board Service (BBS) C-2
Interactive Fast Fax (U.S.A. office) C-3
Technical Support C-3
Limited Warranty C-4

Customer Remedies C-4
Return Process C-5

Ordering Information C-6

Glossary
Index

xii Contents

List of Figures

Figure 2.1 The EtherHub-16i+ Front Panel 2-1
Figure 2.2 The EtherHub-16mi
Figure 2.3 SmartWatch

Figure 2.4 SmartWatch

 LED Panel for EtherHub-16i
 LED Panel for EtherHub-16mi+2-2

Figure 2.5 Daisy-Chain Switch Setting 2-15
Figure 2.6 The EtherHub-16i
Figure 2.7 The EtherHub-16mi

+

Front Panel 2-1

+

Rear Panel 2-16

+

Rear Panel 2-16

+

2-2

Figure 3.1 Stacking Hubs without a Rack 3-3
Figure 3.2 Mounting Hubs Using a Mounting Rack 3-4
Figure 3.3 Connecting Hub’s Serial Port to

Figure 3.4 Connecting Hub’s Serial Port to

PC COM Port 3-7
a Modem 3-8

Figure 3.5 Connect ing Remote PC’s Seria l Port to a Mo dem 3-9
Figure 4.1 Communication Port Dialog Box 4-6
Figure 4.2 DCE/DTE Dialog Box 4-7
Figure 4.3 Phone List Menu 4-7
Figure 4.4 Main Menu 4-7
Figure 5.1 Attaching All Hubs in Stack to One Segment 5-1
Figure 5.2 Attaching Hubs in Stack to 3 Segments 5-2
Figure 5.3 Linking Part of the Stacked Hubs to a Segment 5-3
Figure 5.4 Stacked Hubs Not Linked to a Segment 5-4
Figure 5.5 Linking Stacked Hubs to Unmanaged Hubs

with STP Port Connection 5-5

Figure 5.6 Linking Stacked Hubs to a Network

Management Station 5-6
Figure 5.7 Linking Segments in a Stacked System 5-7
Figure 5.8 Linking a Distributed Segment 5-8
Figure 5.9 Linking Distributed Multi-Segments 5-9
Figure 5.10 System Applied in Novell NetWare IPX

Environment 5-10
Figure 5.11 System Applied in TCP/IP Environment 5-11

xiii

Chapter 1: Overview

The EtherHub 1500 System

The EtherHub 1500 System is a powerful and innovative LAN
network enhancement and management product series. Each
component in the system supports a multi-segment bus
architecture that enhances traffic management and network
bandwidth utilization. This system offers the network manager
a wide range of flexible configuration options, allowing you to

effectively increase your network’s bandwidth. In addition, the
entire installation can be monitored and controlled through any
network management station.

The major components of this network system include:

EtherHub-16mi+, a 16-port intelligent hub with an SNMP-

based network management agent for monitoring and
controlling various network components. It includes -

• 16 RJ-45 STP station ports for connecting computers to the

network using shielded or unshielded twisted-pair cable

• 1 optional port for installing an AUI, BNC or Fiber-Optic

module, which permits connection to thick or thin Ethernet
or 10BASE-F cable

• 2 FlexBus 1500 ports for connecting to compatible hubs via

a FlexBus 1500 STP cable

• RJ-45 port 16 which can also be converted to a daisy-chain

port (

• SmartWatch LED panel that provides an easy way to

configure and monitor the system

) using the daisy-chain switch

1-1

EtherHub 1500 System User’s Guide

In addition, this hub supports a multi-segment bus architecture
that enhances traffic management and network bandwidth
utilization. With an SNMP agent, this unit not only functions
as an intelligent hub, but can also monitor up to 10 intelligent
hubs connected to it (including itself) through the FlexBus 1500
port connection. The EtherHub-16mi

+

conforms to both the
IEEE 802.3 repeater specification and the Simple Network
Management Protocol (SNMP).

This hub supports both in-band and out-of-band management.
For in-band management, it uses Accton’s optional Network
Management Software, called AccView/Open (not included
with this package) to monitor and control a stacked system. For
out-of-band management, the device’s RS232 port can be
connected to a PC and managed using Accton’s EtherHub 1500
System Configuration Program. Any computer (i.e., XT, AT)
with a COM1~4 RS232 port, at least 640 KB on-board memory ,
and a monochrome, EGA or VGA display can be used.

+

The Etherhub-16mi

can be configured as a stand-alone system
to form a simple LAN networking 2 to 16 computers using the
RJ-45 ports. Or it can be connected to other hubs using the
FlexBus 1500 port connection. Further network expansion can
be achieved using the BNC, AUI or fiber-optic trunk port
connection (optional ALT PORT), or the RJ-45 daisy-chain
port. Workstations are connected to the EtherHub-16mi

+

station ports using shielded or unshielded twisted-pair cable.

1-2 Overview

EtherHub 1500 System User’s Guide

EtherHub-16i+, a 16-port intelligent 10BASE- T hub. It includes -

• 16 RJ-45 STP station ports for networking computers to the

network using shielded or unshielded twisted-pair cable
(STP or UTP).

• 1 optional port for installing an AUI, BNC or Fiber-Optic

module, which permits connection to thick or thin Ethernet
or 10BASE-F cable.

• 2 FlexBus 1500 ports for connecting to compatible hubs or

to the EtherHub-16mi

+

via a FlexBus 1500 cable.

• RJ-45 port 16 which can be converted to a daisy-chain port

) using the daisy-chain switch.

(

• Comprehensive LED indicators on the front panel to provide

easy and quick configuration and monitoring the unit.

+

As an intelligent hub, the EtherHub-16i

collects port statistics
and records events for system administration. When stacked with
other intelligent hubs through the FlexBus 1500 ports and
connected to an SNMP management device (e.g., EtherHub-

+

), you can monitor and control all attached hubs through

16mi
in-band and out-of-band communication.

The EtherHub-16i

+

can be used in a stand-alone configuration
to form a simple LAN networking 2 to 16 computers using the
RJ-45 ports. Further network expansion can be achieved using
the BNC, AUI or fiber-optic trunk port connection (optional
ALT PORT), or the RJ-45 daisy-chain port. Workstations are
connected to the EtherHub-16i

+

station ports using shielded or

unshielded twisted-pair.

AccView/Open (SW6102), a Windows-based network

management software package that analyzes and displays data
from the EtherHub-16mi
user to the EtherHub-16mi

+

and transmits commands from the

+

. AccView should be installed on
the network management station (i.e., any workstation used to
manage the network). If segmented architecture is used, the
network management station should be on the same segment as

Overview 1-3

EtherHub 1500 System User’s Guide

the SNMP management agent (i.e., EtherHub-16mi+). The
network management station can be a 386 or 486 workstation
with a 10MB hard disk, at least 2 MB on-board memory, a
VGA display, and running Windows version 3.1 or higher (i.e.,

Windows 3.1, 3.11, ’95, NT).

AccView/Open EtherHub Manager, is network management

software specifically designed to manage Accton’s EtherHub
family. This software can be integrated into the following
third-party management platforms -

• SunNet Manager/Sparc (SW6120-1)

• SunNet Manager/X86 (SW6120-2)

• OpenView/Windows (SW6121)

• OpenView/Sparc (SW6122)

• Novell Netware Managment System (SW6124)

Alternative Interface Module -

• BNC (EH1551),

• AUI (EH1552)

• Fiber Optic (EH1553)

Security Kit (SW7300), for intrusion/eavesdropping protection

default module preinstalled in EH1500

Features of EtherHub 1500 System

• Conforms to the SNMP & IEEE Hub Management

Standards, MIB I and MIB II

• Conforms to the IEEE 802.3 repeater specification and the

10BASE-T standard

• Manages up to 10 concentrators using the FlexBus 1500

(STP) cable

• One optional port (BNC, AUI or Fiber-Optic) for connecting

to any Ethernet media via slide-in alternative module
transceiver

1-4 Overview

EtherHub 1500 System User’s Guide

• Provides one serial 9-pin RS232 port for out-of-band

network management (EtherHub-16mi

• Supports daisy chaining by using a daisy-chain switch to

+

only)

convert port 16 to a daisy-chain port

• Automatic polarity detection and correction permits

automatic recovery due to wiring errors

• Automatically partitions bad port to protect network

• Adapts to universal wide range voltage power

(i.e., 100V AC to 240V AC +/- 10%, 50~60 +/- 3Hz)

• Flexible installation for desktop, wall mount, or rack

installation (standard 19” size)

Distinguishing Factors of EtherHub 1500 System

• Provides multi-segment architecture allowing the network to

be split into three segments

• Includes a SmartWatch comprehensive LED indicator

panel for reporting network activity, unit configuration and
facilitating problem diagnosis

• Automatic ID assignment and auto-terminator setting for

auto-configuration

• Supports fault-tolerant configuration by allowing port link

backup and agent backup

• Two FlexBus 1500 management ports (BUS IN/OUT) for a

bundled cable containing 3 separate Ethernet segments and
a management link

• Provides front panel configuration using a Configure button

Overview 1-5

EtherHub 1500 System User’s Guide

• Supports out-of-band management (using Accton’s proprietary

EtherHub 1500 System Configuration Program), and full
software configurable in-band manag ement using the optional
AccView/Open (network manag ement software)

• Flash ROM on board the EtherHub-16mi

+

for easily updating

the SNMP agent using AccView/Open’s download option

• Stacked hubs can be distributed up to 100-meters in a single

segment configuration

1-6 Overview

Chapter 2: Hardware Description

This chapter describes the hardware features of the EtherHub-16i
and EtherHub-16mi+. Except for 3 LED indicators that are unique
to each hub, both products have similar indicators and other front
panel components. Likewise, the rear panel is similar for both
versions, except that the EtherHub-16i
232 serial port. Before connecting any network device to the hub,
read this chapter carefully. For easier management and control of
the hub, familiarize yourself with the front panel indicators and

Configure button.

Front Panel Displays

Figure 2.1 The EtherHub-16i+ Front Panel

+

does not support the RS-

+

Figure 2.2 The EtherHub-16mi+ Front Panel

2-1

EtherHub 1500 System User’s Guide

SmartWatch LED Panel

Both hubs have a SmartWatch LED panel that includes
comprehensive indicators for monitoring the device and
network status. A quick glance at the front panel tells you if

the unit’s power in ON, if it is monitoring another hub (or
concentrator), or if a problem exists on the network. The
following sections describe the function of each indicator.

Figure 2.3 SmartWatch LED Panel for EtherHub-16i

Figure 2.4 SmartWatch LED Panel for EtherHub-16mi

+

+

2-2 Hardware Description

EtherHub 1500 System User’s Guide

PWR/CPU

Color: Green
Label: PWR/CPU
Function: Power indicator

LED Activity Condition Indication

STEADY LIGHT ON Unit is receiving power, CPU is running,

and EH1502s Agent is in Master mode.

BLINKING LIGHT ON Unit is receiving power, CPU is running,

and EH1502s Agent is in Slave mode.

NO LIGHT OFF Power is disconnected; no power received.

Interhub

Color: Green
Label: Interhub
Function: Indicates a valid connection between hub and agent

LED Activity Condition Indication

BLINKING LIGHT ON Hub has a valid connection to the Agent through

the FlexBus 1500 port on the back plane.

NO LIGHT OFF Hub is in a stand-alone configuration. Or hub

does not have a valid connection to the network
system it monitors.

Isolated (EtherHub-16i+ only)

Color: Green
Label: Isolated
Function: Indicates the hub is isolated from Ethernet segment

of the FlexBus 1500 backplane

LED Activity Condition Indication

STEADY LIGHT ON Hub is isolated from all segments.
NO LIGHT OFF Hub is attached to one of the 3 segments of

the FlexBus 1500.

Hardware Description 2-3

EtherHub 1500 System User’s Guide

Serial (EtherHub-16mi+ only)

Color: Green
Label: Serial
Function: Indicates connection to a management console

LED Activity Condition Indication

BLINKING LIGHT ON Agent has a valid connection to a

management console using its RS232 serial
port. A valid link only occurs when the
management console is sending a message
to or receiving a message from the agent.

NO LIGHT OFF No connection to a management console.

Terminator

Color: Green
Label: Terminator
Function: Indicates if a unit is located in a terminal position

in a stacked system

The unit has an auto-terminate function that is enabled when it
is at the end of a stack. In a stand-alone configuration, this
LED is ON because of the auto-terminate function.

LED Activity Condition Indication

STEADY LIGHT ON The hub is at the end of a stacked
NO LIGHT OFF The hub is connected to a stacked

2-4 Hardware Description

system or in a stand-alone configuration.
system, but not at the terminal position of

a stack.

EtherHub 1500 System User’s Guide

Monitor (EtherHub-16i+ only)

Color: Green
Label: Monitor
Function: Indicates that an SNMP management agent is

connected to and managing the hub

LED Activity Condition Indication

BLINKING ON Hub is connected to and managed by an

Agent.

NO LIGHT OFF Hub is not connected to an Agent.

SNMP (EtherHub-16mi+ only)

Color: Green
Label: SNMP
Function: Indicates that an SNMP frame is being received by

the Agent

LED Activity Condition Indication

BLINKING LIGHT ON Hub is presently receiving an SNMP frame.
NO LIGHT OFF Hub is not receiving an SNMP frame.

In a stacked system where a Master and Slave agent exist, the
SNMP LED of the active agent will blink if an SNMP frame is
received. Normally, this would mean that the Master agent’s
SNMP LED will be ON. However, if the Master agent fails, the
Slave agent’s SNMP LED should light up. See the section on

Master Agent in Chapter 4 for related information.

Hardware Description 2-5

EtherHub 1500 System User’s Guide

Jabber

Color: Red
Label: Jabber
Function: Jabber lock-up indicator

Jabber refers to an abnormal Ethernet frame transmission. The
frames causing jabber are normally much too long. This may
result from a malfunctioning Ethernet card and may cause data
loss for all network users.

LED Activity Condition Indication

STEADY LIGHT ON Jabber exists on one or more port

connection (i.e., RJ-45 or ALT port).

NO LIGHT OFF No jabber occurring.

I

IMPORTANT

connections one by one, as follows:

1. Select a port to check.

2. Then unplug its cable connection while checking the Jabber display.
If the Jabber LED goes OFF, you have successfully identified the
defective port. However, if the light remains ON, the port is in good
condition.

3. Replug the cable connection, and select another port to test.

4. Repeat this procedure until you find the port causing the problem.

!

To identify the port causing the problem, check all existing

2-6 Hardware Description

EtherHub 1500 System User’s Guide

Alert

Color: Yellow
Label: Alert
Function: Indicates hardware or hub ID setting problems

LED Activity Condition Indication

BLINKING LIGHT ON Hardware or hub ID setting error has occurred.
NO LIGHT OFF No abnormal occurence.

The Alert LED indicates that the device has encountered a problem

F

in one or more hardware components (e.g., EEPROM checksum
error, or Configure button is locked). However, the unit can still
function even if the Alert LED is on. It is also used as a diagnostic
test LED. Refer to the section on
later in this chapter for more information.

Utilization

Label (%) Color Function

1% 5% 15% Green Indicates percentage
30% Amber (yellow) utilization of LAN bandwidth.
65+% Red

Diagnostic Test LED Indicators

The Utilization LEDs indicate the percentage of network
bandwidth used by valid data. The hub updates this display
every 0.5 seconds.

There are 5 LEDs representing the percentage of network
utilization. The corresponding LEDs light to show that the
percentage utilization of LAN bandwidth has reached this level.
When active, these LEDs look like a stereo’s equalizer display.

For example, if network utilization reaches 1%, the LED
labeled 1% will light. However, if network utilization rises
above 1% (e.g., 30%), the LED labeled 30 and all the other
LEDs before it (i.e., 1, 5, and 15) will light in rapid succession.

Hardware Description 2-7

EtherHub 1500 System User’s Guide

These LEDs monitor the share of valid network frames
transmitted by this hub within a 10Mbps bandwidth. They
provide a quick way to monitor the current traffic load relative
to the network’s capacity.

Collision

Label (%) Color Function

1% 3% 5% Green Indicates the percentage of packet
10% Amber (yellow) collisions occurring out of the total
15+% Red packets received by the hub.

Collisions occur when two or more devices connected to a hub
attempt to transmit data simultaneously on the network. When
a collision occurs, devices pause and then re-transmit after a
pseudo-random wait period. Because wait periods differ among
devices, successive collisions become increasingly improbable.

The Collision LEDs assist the network manager in monitoring
the percentage of packet collisions occurring relative to the total
packets received by the hub. Similar to Utilization LEDs, the
Collision LEDs have 5 numbers representing collision percentag e.
When collisions reach a level marked on the LED display, the
corresponding LED lights up.

For example, if packet collisions reach 1%, the LED labeled
1% will light up. However, if collisions go beyond 1% (e.g.,
15%), the LED labeled 15+ and all the other LEDs before it
(i.e., 1, 3, 5, and 10) will also light up in rapid succession.

When more than 31 consecutive collisions occur on the cable

F

2-8 Hardware Description

segment connected to a port, that port is automatically partitioned
by the hub. The hub automatically reconnects this port when a data
packet longer than 512 bits (normal) is transmitted or received by
the partitioned port without collision. This applies to all STP ports
and the ALT PORT.

EtherHub 1500 System User’s Guide

Segment LED Indicators

Color: Green
Label:

Function: Indicates which segment is attached to the hub
There are 3 Ethernet segments embedded in the FlexBus 1500

ports located on the back plane of the EtherHub 1500 series.
These units can be attached to any one of the three Ethernet
segments. The 3-segment LED indicator displays a
combination of ON/OFF lights to show which segment the unit
is connected to. The table below shows the possible LED
display combination of the segment indicators marked "1 2 3"
and their corresponding meaning.

Segment Description

1 2 3
ON OFF OFF Hub is connected to Segment 1 (Default)
OFF ON OFF Hub is connected to Segment 2
OFF OFF ON Hub is connected to Segment 3

The EtherHub-16i+ can be completely isolated except for the

F

management channel (which is reflected via the Isolated LED).
However, the EtherHub-16mi

+

can not be physically isolated.

Hardware Description 2-9

EtherHub 1500 System User’s Guide

Hub ID Indicators

Color: Green
Label:

Function: Indicates Unit ID Setting
In a stacked system, each hub unit has a unique ID. The EtherHub

1500 hub series is equipped with a function that automatically sets
the hub ID, freeing the user from this task. The table below shows

possible display combinations for the hub unit’s ID LED indicators
marked "1 2 4 8" and their corresponding meaning. These LEDs
display the binary equivalent of the selected ID number (displayed
left to right). In normal operation, the LEDS turned ON display a
steady light; while in configuration mode, they blink.

Hub ID LED 1 Hub ID LED 2 Hub ID LE D 4 Hub ID LE D 8 Hub ID Number Setting

ON ON ON ON (DEFAULT) Used for

automatic Hub ID setting.
ON OFF OFF OFF Hub ID 1
OFF ON OFF OFF Hub ID 2
ON ON OFF OFF Hub ID 3
OFF OFF ON OFF Hub ID 4
ON OFF ON OFF Hub ID 5
OFF ON ON OFF Hub ID 6
ON ON ON OFF Hub ID 7
OFF OFF OFF ON Hub ID 8
ON OFF OFF ON Hub ID 9
OFF ON OFF ON Hub ID 10

Port Status Indicators

There are 17 pairs of port status LED indicators. Each pair
consists of a PARTITION/DISABLE LED (top row) and
LINK/TRAFFIC LED (bottom row). Each pair (or column) has
a label referring to the port number the LEDs monitor. For
example, the port status LED pair labeled ALT monitors the
optional port found at the rear panel (labeled ALT PORT). The
other 16 pairs are for the RJ-45 ports on the front panel of the hub.

2-10 Hardware Description

EtherHub 1500 System User’s Guide

PARTITION/DISABLE

LED Activity Condition Indication

STEADY RED LIGHT PARTITION Indicates port partitioning due to an

abnormal network condition.
BLINKING RED LIGHT DISABLE Indicates the port has been disabled
NO LIGHT OFF Port is in good condition.

The PARTITION/DISABLE LEDs are also used as diagnostic LEDs.

F

Please refer to the
for more information.

Partition

Diagnostic Test LEDs

section later in this chapter

A port is temporarily partitioned when a line error or too many
collisions are detected on the attached segment. While it is
automatically partitioned, the port continues to receive data
from the segment. However, data is not transmitted onto the
segment. When the problem is corrected or a valid data packet
is received through the port, the port is automatically
reconnected. When partitioning occurs, the port’s
corresponding PARTITION/DISABLE LED will be continually
lit (RED light). Otherwise, this LED should be OFF (unlit).

Disable

Disabling a port is the same as manually partitioning it, except
that you must also manually reconnect it. You can choose to
partition a port even if there is nothing wrong with it. For
example, to prevent a certain device from accessing the network
or to reduce network traffic you may opt to disable the port. No
incoming packet transmission can occur on a disabled port.
Ports can be disabled/enabled using Accton’s AccView/ Open
or the EtherHub 1500 System Configuration Program. They
can also be enabled by activating the factory default settings.
See the section on

Reset Mode in Chapter 4 for information on

reverting to default settings.

Hardware Description 2-11

EtherHub 1500 System User’s Guide

LINK/TRAFFIC

LED Activity Condition Indication

STEADY GREEN
LIGHT
BLINKING GREEN
LIGHT
NO LIGHT OFF No valid link has been established on this port.

ON Indicates a valid link has been established on this

port.

ON Indicates the port is receiving packets; blinking is

proportional to the traffic passing through the port.

Link

The corresponding LINK/TRAFFIC LED should light up when
a device (e.g., computer, hub or bridge) establishes a valid
connection using the RJ-45 port. However, for the ALT PORT,
no link connection is tested. The LINK/TRAFFIC LED for
ALT only monitors the traffic condition.

TROUBLESHOOTING

If the LINK/TRAFFIC LED does not light up when a device is connected
to its corresponding port, check that both the hub and connected device
are powered on. For devices connected to the hub using an STP or
UTP cable, check that the cable length does not exceed 100 meters.
You should have standard, straight cables and not cross-over or other
specialized cables.

Traffic

Traffic refers to the movement of packets being received by the
port. A port’s corresponding LINK/TRAFFIC LED will blink
(ON) in proportion to the rate of traffic passing through the
port. Through this LED, the network manager can easily view
the activity on a port.

2-12 Hardware Description