HP 24S Reference guide

HP 24S Reference guide
HP EtherTwist
Hub and Hub Plus
Installation and
Reference Guide
Copyright Hewlett-Packard Company 1992. All rights reserved.
Hewlett-Packard Company makes no warranty of any kind with regard to this material, including, but not limited
to, the implied warranties of merchantability and fitness for a particular purpose. Hewlett-Packard shall not be
liable for errors contained herein or for incidental or consequential damages in connection with the furnishing,
performance, or use of this material.
This document contains proprietary information, which is protected by copyright. No part of this document may
be photocopied, reproduced, or translated into another language without the prior written consent of
Hewlett-Packard. The information contained in this document is subject to change without notice.
Print History:
Edition 1, March 1991
Edition 2, March 1992
Edition 3, June 1992
Safety Considerations
The product and related documentation must be reviewed for familiarization with safety markings and
instructions before installation and operation. See the documentation section entitled “Safety Information”.
Informations concernant la sécurité
Ce produit et la documentation s’y rapportant devront être étudiés avant l’installation et l’utilisation, afin de se
familiariser avec les symboles et instructions de sécurité. Reportez-vous à la section «Informations concernant la
sécurité».
Hinweise zur Sicherheit
Sehen Sie sich das Produkt an und lesen Sie die begleitende Dokumentation, damit Sie vor der Installation und
dem Betrieb mit den Sicherheitsmarkierungen und Anleitungen vertraut sind. Bitte lesen Sie das Kapitel mit der
Überschrift “Hinweise zur Sicherheit”.
Considerazioni sulla sicurezza
Esaminare il prodotto e la relativa documentazione per familiarizzarsi con gli avvisi e le istruzioni di sicurezza
prima dell’installazione e dell’uso. Vedere la sezione di questo documento intitolata “Considerazioni sulla
sicurezza”.
Consideraciones sobre seguridad
Antes de instalar y hacer funcionar el producto, se deben estudiar el producto y la documentación relacionada a
fin de familiarizarse con las indicaciones de advertencia e instrucciones. Ver la sección del documento titulada
“Consideraciones sobre seguridad”.
HP 28684B Hub/12
HP 28688B Hub Plus
HP 28699A Hub Plus/48
HP EtherTwist Hub and Hub Plus
Installation and Reference Guide
HP Part Number: 5090-2692
Printed in U.S.A.
June 1992
Edition 3
E0692
What Is In This Guide
This guide contains information to help you install, configure, and troubleshoot your
HP 28684B EtherTwist Hub/12, HP 28688B EtherTwist Hub Plus, and HP 28699A
EtherTwist Hub Plus/48. The guide is organized as follows:
Chapter 1 provides a brief introduction to the hubs. It describes important product
features, what you should have received with your hub, and an overview of how the hub
works.
Chapter 2 provides hub installation instructions. It describes, in detail, the steps that
you should follow to install the hubs.
Chapter 3 describes all the hubs’ console interface commands.
Chapter 4 contains troubleshooting information. If you experience problems with the
hubs, you should refer to this chapter.
Appendix A provides information on the cables and connectors that you should use to
connect the hubs to the other devices in your network.
Appendix B contains the technical specifications for the hubs.
Appendix C describes how to configure commonly found modems for use with the hubs’
console connection.
Appendix D is applicable only for the HP 28688B and HP 28699A and provides
information on network addressing for those using SNMP network management stations
to manage the hubs over IP and IPX networks.
Appendix E is applicable only for the HP 28688B and HP 28699A and provides
information on establishing a backup connection for a critical link to another hub in your
network topology.
Safety Information contains safety information about the hubs. You should read and
understand this information before you use the product.
2
Contents
1
2
Introducing the HP EtherTwist Hub/12, Hub Plus, and Hub Plus/48
Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Included Parts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Front of the Hub . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Status LEDs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Back of the Hub . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Status LEDs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
How the Hub Works . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Collision Detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Auto-Segmentation . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Link Beat . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Firmware Enhancements (HP 28688B and HP 28699A Only) . . . . . . . .
Network Management (HP 28688B and HP 28699A Only) . . . . . . . . .
Upgrading the HP 28684B to an HP 28688B . . . . . . . . . . . . . . . . .
Installation
Installation Summary . . . . . . . . . . . . . . . . . . . . . . .
1. Mount the hub . . . . . . . . . . . . . . . . . . . . . . . .
Mounting the HP 28684B EtherTwist Hub/12 and
HP 28688B Hub Plus . . . . . . . . . . . . . . . . . . . .
Mounting the HP 28699A Hub Plus/48 . . . . . . . . . . .
2. Plug in the hub and verify its operation . . . . . . . . . . .
3. Connect the hub to device and networks . . . . . . . . . . .
Connecting Computers . . . . . . . . . . . . . . . . . . . .
Connecting to a Network Backbone . . . . . . . . . . . . .
Connecting Other Hubs . . . . . . . . . . . . . . . . . . .
Port Connections . . . . . . . . . . . . . . . . . . . . . . . . . .
Twisted-Pair Port . . . . . . . . . . . . . . . . . . . . . . . .
ThinLAN Port . . . . . . . . . . . . . . . . . . . . . . . . . .
AUI Port . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4. Customize the hub’s configuration (if needed) . . . . . . . .
Console Connection . . . . . . . . . . . . . . . . . . . . . .
Connecting a Modem and Terminal . . . . . . . . . . . . .
If You Have Trouble with a Terminal or Modem Connection
Configuration Commands . . . . . . . . . . . . . . . . . . . .
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. 1-1
. 1-3
. 1-4
. 1-4
. 1-5
. 1-5
. 1-6
. 1-6
. 1-7
. 1-7
. 1-8
. 1-8
. 1-10
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2-1
2-2
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2-3
2-5
2-7
2-8
2-8
2-8
2-9
2-10
2-10
2-12
2-13
2-14
2-14
2-15
2-16
2-17
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3
3
4
A
4
Operation
Starting the Console Session . . . . . . . . . . . . .
Console CommandsHP 28699A;console commands .
HElp . . . . . . . . . . . . . . . . . . . . . . .
HElp <command> . . . . . . . . . . . . . . . .
BAckup (HP 28688B and HP 28699A Only) . .
COunters . . . . . . . . . . . . . . . . . . . .
DIsconnect . . . . . . . . . . . . . . . . . . .
IPconfig (HP 28688B and HP 28699A Only) .
PAssword (HP 28688B and HP 28699A Only) .
PIng (HP 28688B and HP 28699A Only) . . .
POrt <port> <ON/OFF> . . . . . . . . . . . .
REset . . . . . . . . . . . . . . . . . . . . . .
SPeed <new speed> . . . . . . . . . . . . . . .
STatus <port group> . . . . . . . . . . . . . .
TEstlink . . . . . . . . . . . . . . . . . . . . .
THinwatch <ON/OFF> . . . . . . . . . . . . .
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. 3-1
. 3-2
. 3-2
. 3-2
. 3-3
. 3-4
. 3-4
. 3-5
. 3-7
. 3-7
. 3-8
. 3-8
. 3-8
. 3-9
. 3-10
. 3-10
Troubleshooting
Basic Troubleshooting Tips . . . . . . .
Diagnosing With the LEDs . . . . . . . .
Diagnostic Tests . . . . . . . . . . . . .
Testing the Hub Only . . . . . . . . .
Testing the Hub’s Ports and the Links
Testing Twisted-Pair Cabling . . . . .
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Cables and Connectors
HP Cables . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Other Standard Cables . . . . . . . . . . . . . . . . . . . . .
Twisted-Pair Cable/Connector Pin-Outs . . . . . . . . . . . .
Twisted-Pair Cable for Hub-to-Computer Connection . . . .
Twisted-Pair “Crossover” Cable for Hub-to-Hub Connection
Twisted-Pair Cable Pin Assignments . . . . . . . . . . . . .
Twisted-Pair Straight-Through Cable . . . . . . . . . . .
Twisted-Pair Crossover Cable . . . . . . . . . . . . . . .
Thin LAN Cable Requirements . . . . . . . . . . . . . . . . .
AUI Cable . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
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. A-2
. A-3
. A-4
. A-4
. A-5
. A-6
. A-6
. A-6
. A-6
. A-7
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4-1
4-3
4-4
4-4
4-5
4-5
B
C
D
Console Connector and Cable Pin-Outs . . . . . . . . . . .
Pin-Out for Hub’s Console Port Connector . . . . . . . .
RS-232-C “Crossover” Cable
(for Terminal/PC with 25-Pin Connector) . . . . . . . .
RS-232-C “Crossover” Cable
(for Terminal/PC with 9-Pin Connector) . . . . . . . .
RS-232-C Cable for HP 110 . . . . . . . . . . . . . . . .
Null-Modem Adapter
(use with a modem cable when connecting a terminal) .
RS-232-C Modem Cable . . . . . . . . . . . . . . . . . .
Console Port Loopback Connector . . . . . . . . . . . . . .
. . . . . . . . . . . A-10
. . . . . . . . . . . A-11
. . . . . . . . . . . A-11
Specifications
HP 28684B Hub/12 and HP 28688B Hub Plus
Physical . . . . . . . . . . . . . . . . . . .
Electrical . . . . . . . . . . . . . . . . . .
Environmental . . . . . . . . . . . . . . .
Cable Interfaces . . . . . . . . . . . . . . .
Electromagnetic . . . . . . . . . . . . . . .
Datacomm Declarations . . . . . . . . . .
HP 28699A Hub Plus/48 . . . . . . . . . . . .
Physical . . . . . . . . . . . . . . . . . . .
Electrical . . . . . . . . . . . . . . . . . .
Environmental . . . . . . . . . . . . . . .
Cable Interfaces . . . . . . . . . . . . . . .
Electromagnetic . . . . . . . . . . . . . . .
Datacomm Declarations . . . . . . . . . .
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. B-1
. B-1
. B-1
. B-1
. B-2
. B-2
. B-2
. B-3
. B-3
. B-3
. B-3
. B-3
. B-4
. B-4
Modem Configuration
HP 35031A Support Link II . . . . . . . . . . . . . . . . .
HP 50759A Support Link . . . . . . . . . . . . . . . . . .
HP 37212B Support Link . . . . . . . . . . . . . . . . . .
Black Box V.32 9600 Async. . . . . . . . . . . . . . . . . .
Hayes 1200 Smartmodem (for both 8-and 10-switch units)
Racal Vadic Maxell 2400 VP (Hayes 2400 Compatible) . .
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. C-1
. C-1
. C-1
. C-2
. C-2
. C-2
Network Addressing (HP 28688B and HP 28699A Only)
IPX Addressing for Novell NetWare . . . . . . . . . . . . .
IPX Addressing Notes: . . . . . . . . . . . . . . . . . . . .
IP Addresses for IP and Non-IP Networks . . . . . . . . . . .
Using Assigned IP Addresses . . . . . . . . . . . . . . . . .
Building Your Own IP Addressing Scheme . . . . . . . . .
Example Addressing Scheme . . . . . . . . . . . . . . . . .
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A-8
A-8
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A-9
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A-9
A-10
D-1
D-2
D-2
D-2
D-3
D-3
5
E
Backup Links (HP 28688B and HP 28699A Only)
Description . . . . . . . . . . . . . . . . . . . . . .
Limitations . . . . . . . . . . . . . . . . . . . . . .
Additional Notes . . . . . . . . . . . . . . . . . . .
Configuring a Backup Link . . . . . . . . . . . . . .
Identifying the Backup Link . . . . . . . . . . . . . .
Indications of Backup Link Activation . . . . . . . .
Reactivating the Primary Link . . . . . . . . . . . .
Sample Topologies . . . . . . . . . . . . . . . . . . .
Sample 1: EtherTwist Hub-to-EtherTwist Hub . .
Sample 2: Backup Link Using Alternative Medium
Safety Information
Regulatory Statements
One-Year Limited Hardware Warranty
Index
6
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E-1
E-2
E-2
E-3
E-4
E-4
E-5
E-6
E-6
E-7
1
Introducing the HP EtherTwist Hub/12,
Hub Plus, and Hub Plus/48
The HP 28684B EtherTwist Hub/12, HP 28688B EtherTwist Hub Plus, and HP 28699A
EtherTwist Hub Plus/48 are 10-Mbit/s multiport repeaters used to connect computers and
other networked devices in an unshielded twisted-pair cable network. These hubs are
compatible with the IEEE 802.3 Type 10Base-T standard. See the document HP
EtherTwist Technical Reference Guide (part number 5091-3237E) for network
configuration guidelines.
Features
The HP EtherTwist hubs have the following features:
The following ports:
– 12 twisted-pair ports (HP EtherTwist Hub/12 and HP EtherTwist Hub Plus)
or 48 twisted-pair ports (HP EtherTwist Hub Plus/48) for connection to
twisted-pair cable.
– A ThinLAN port for connection to thin LAN coaxial cable.
– An AUI port for connection to an external transceiver. This additional port
can be used with the appropriate transceiver to connect any media, such as
twisted-pair, thick or thin coaxial, and fiber-optic cable. It can be used at the
same time the other ports are being used.
Note that all the network ports (twisted-pair, ThinLAN, and AUI) are active
and can be used at the same time.
– An RS-232-C console port for attaching a terminal or terminal emulator that
can be used to customize the hub’s configuration, monitor hub activity and
status, and run tests of the hub. Console access can be either local, by direct
attachment to the console port, or remote, through a modem connection.
Introducing the HP EtherTwist Hub/12, Hub Plus, and Hub Plus/48 1-1
Features (continued)
Compatibility with the IEEE 802.3 Type 10Base-T standard and support for both
IEEE 802.3 and Ethernet protocols.
A self-test for fault identification when the hubs are powered on or when they are
reset from the console or from a network management station.
LEDs on both the front and back panels for easy interpretation of the hub’s status.
Automatic segmentation of ports that are experiencing network communication
problems. This improves network integrity and aids in fault isolation.
Segmented ports automatically resume operation when the problems are
corrected. (See “Auto-Segmentation” later in this chapter.)
Support for a backup link to another hub (an automatically-activated redundant
connection) to enhance network fault tolerance. (HP 28688B and HP 28699A only.)
A power supply that automatically adjusts to the voltage range of the ac power
being supplied to the hub (90-120 volts or 200-240 volts). No voltage range setting
or fuse change is needed.
Comes with metal brackets that can be easily attached to the hub for mounting it
in a standard 19-inch telco rack or on a wall.
A factory assigned station address (also called MAC address, Ethernet address, or
physical address) allowing the hub to respond to 802.2 Test packets. The HP
28688B and HP 28699A can also be configured with an IP address and can
respond to an ICMP Echo Request packet (also called “Ping”).
The HP 28688B and HP 28699A can be managed remotely from a network
management station that supports SNMP over IP (using the configured IP
address) or IPX. (See “Network Management” later in this chapter.)
Can be downloaded with new firmware enhancements (HP 28688B and HP
28699A only) either from a PC attached to the console port, or over the network.
(See “Firmware Enhancements” later in this chapter.)
The HP 28684B can be upgraded to a managed HP 28688B Hub Plus by adding
the Upgrade Kit, HP part number J2351A.
1-2 Introducing the HP EtherTwist Hub/12, Hub Plus, and Hub Plus/48
Included Parts
HP EtherTwist Hub/12 (28684-60011)
HP EtherTwist Hub Plus (28688-60011) or
HP EtherTwist Hub Plus/48 (28699-60001)
Accessories kit for the Hub/12 and Hub Plus (5062-9312) or the
Hub Plus/48 (5062-3397), including:
– two mounting brackets for the Hub/12 and Hub Plus (5001-5624) or the
Hub Plus/48 (5001-5641)
– four 10-mm M4 screws (0515-0780)
– four 5⁄8-in number 12-24 screws (2940-0238)
– AUI retainer (5062-3351)
– four self-adhesive rubber feet (0403-0427)
– Velcro BNC “T” connector cover (1252-1650)
A Velcro strap holder attached to each of the hubs’ 50-pin ports (1400-1497)
A 12-port Modular Adapter (included with the Hub/12 and Hub Plus only)
(28638-60001)
HP EtherTwist Hub and Hub Plus Installation Steps (5090-2693)
HP EtherTwist Hub and Hub Plus Installation and Reference Guide (5090-2692)
Power cord, one of the following:
– United Kingdom (8120-1351)
– Australia (8120-1369)
– Europe (8120-1689)
– United States/Canada (8120-1378)
– Switzerland (8120-2104)
– Demark (8120-2956)
– Japan (8120-4753)
Introducing the HP EtherTwist Hub/12, Hub Plus, and Hub Plus/48 1-3
Front of the Hub
HE
PA WLE
CK TT
AR
D
Fib
Hu er-Op
b
PL tic
US
HE
PA WLE
CK TT
AR
D
Hu
Hu b/12
b
Plus
Status LEDs
HP 28684B and HP 28688B
Status LEDs
HP 28699A
Status LEDs
~Line On (green) is ON if the hub is receiving power.
Activity (green) is ON when data is being transmitted. The frequency shows the amount
of traffic. In heavy traffic, it may appear on all the time.
Fault (yellow) is ON if the hub is faulty and needs to be replaced, FLASHING if a port
has been auto-segmented. (See “Auto-Segmentation” later in this chapter.)
1-4 Introducing the HP EtherTwist Hub/12, Hub Plus, and Hub Plus/48
Back of the Hub
Dashed lines show top half of the Hub Plus/48
with additional twisted-pair port groups.
Group selector
button and LEDs
Group B
Group A
Status LEDs
ThinLAN port
Console port
Twisted-pair ports
AUI port
Group D
Group C
Station Address
and
Serial Number
Status LEDs
Power (green) is ON if the hub is receiving power.
(This is the same as ~Line On on the front.)
Activity (green) is ON when data is being
transmitted. The frequency shows the amount
of traffic. In heavy traffic, it may appear on all
the time. (This LED is repeated on the front.)
Fault (yellow) is ON if the hub is faulty and needs to be replaced, FLASHING if a port
has been auto-segmented. (This LED is repeated on the front.)
Collision (yellow) is ON when collisions (two or more nodes trying to transmit on the
network at the same time) are detected on any of the attached cable segments. If
collisions are infrequent (which is normal), the light may be imperceptible. If it appears
on continuously, see chapter 4, “Troubleshooting”.
Introducing the HP EtherTwist Hub/12, Hub Plus, and Hub Plus/48 1-5
Port LEDs (green), one for each network port, are ON when the corresponding port is
enabled and functioning normally. Ports can be enabled and disabled using the Port
command on the hub’s console. The AUI port LED is always ON when that port is
enabled, even if it is not being used. For the twisted-pair ports the LED will be OFF if the
link beat signal is not received from the device connected to that port. Each Port LED will
FLASH if the port has been auto-segmented (see “Auto-Segmentation” later in this
chapter).
To view the twisted-pair port LEDs on the HP EtherTwist Hub Plus/48, press the Group
Selector button until the port group you wish to view (group A, B, C, or D) is displayed.
The group selector LED identifies which port group is being displayed by the twisted-pair
port LEDs.
How the Hub Works
The HP EtherTwist Hub/12, Hub Plus, and Hub Plus/48 are multiport repeaters. Data
signals coming into the hub from any of its ports are automatically regenerated and
transmitted to all the other hub ports. The hub regenerates the data without interpreting
the contents, so it can be used in either IEEE 802.3 or Ethernet networks and with any
upper-level protocol.
Collision Detection
These hubs also perform collision detection. A collision occurs when two nodes try to
transmit at the same time. When the hub detects this, it stops repeating the colliding
transmissions and starts transmitting a jamming signal. The jamming signal tells the
transmitting nodes that a collision has occurred. The colliding nodes then stop
transmitting for a random amount of time before attempting to retransmit the data. Once
the collision condition is removed, the hub stops transmitting the jamming signal and
normal operation is restored.
1-6 Introducing the HP EtherTwist Hub/12, Hub Plus, and Hub Plus/48
Auto-Segmentation
These hubs will automatically disable (auto-segment) a port if it experiences excessive
collisions (greater than 30 consecutive collisions). The port will automatically return to
operation if the excessive collision condition is removed and normal traffic is restored.
Auto-segmentation can also be caused by improper termination of cabling attached to the
AUI or ThinLAN ports, or by having nothing attached to the ThinLAN port when it is
enabled.
If a port is auto-segmented, its port LED and the Fault LEDs will flash. A segmented
ThinLAN port will not cause the Fault LED to flash unless Thinwatch has been explicitly
enabled with the Thinwatch console command. The Thinwatch command is described in
chapter 3.
If a port is auto-segmented, only the LAN segment attached to that port is affected. The
other LAN segments will operate normally.
If a port is disabled explicitly, by using the console port, or from an HP network
management station, (HP 28688B and HP 28699A only) it must be enabled explicitly. It
will not be enabled automatically.
Link Beat
Type 10Base-T devices use a signal called link test pulse (link beat in HP documentation).
This signal informs a hub of the presence of a device connected to it over twisted-pair cable
and the integrity of the twisted-pair link between them. If your network has a mixture of
10Base-T and non-10Base-T products, you may have to disable link beat on some of them.
For the HP EtherTwist hubs, disable link beat on any port that is connected to a
non-10Base-T device. You can do this through the Link beat console command (see
chapter 3, “Operation”, in this manual for command details), or from an HP network
management station (HP 28688B and HP 28699A only — see the network management
product documentation for instructions).
The hub will not transmit packets out ports that do not sense the link beat signal unless
link beat is disabled on that port.
Introducing the HP EtherTwist Hub/12, Hub Plus, and Hub Plus/48 1-7
Firmware Enhancements (HP 28688B and HP 28699A
Only)
Hewlett-Packard continually tests and improves its products. When firmware
enhancements are made to the HP 28688B and HP 28699A hubs, you will be able to easily
update them with the new code. The update can be made from a PC attached to the hub’s
console port (directly or through a modem), or the hub’s new code can be downloaded over
the network. The update procedures are described in documents that come with the new
code.
The firmware, called the agent code, enables a managed device to respond to requests for
data from the HP OpenView Network Management station.
Contact your HP-authorized LAN dealer or local HP sales office for the latest on firmware
enhancements to the HP 28688B and HP 28699A hubs.
Network Management (HP 28688B and HP 28699A Only)
The agent code firmware on the HP EtherTwist Hub Plus and Hub Plus/48 allows them to
be managed remotely by any network management product that complies with the Simple
Network Management Protocol (SNMP) standard. HP offers SNMP-compliant network
management products; both DOS-based and UNIX-based versions are available. These
products use a windows interface to:
manage multiple HP hubs and other HP network devices
automatically generate a graphic display of the network map
gather network traffic statistics
configure ports
run tests of the hub
test network links to other devices
Note
The functionality provided by HP network management products is
improved on a regular basis. For more information on the capabilities of
these products, contact your HP-authorized LAN dealer or local HP sales
office.
1-8 Introducing the HP EtherTwist Hub/12, Hub Plus, and Hub Plus/48
Network Address. The communication between the hub and the network management
station requires that the hub be assigned a network address. If you are using your hub in
a Novell NetWare network, it can be automatically configured with an IPX address from
an IPX router on the network. The hub is preconfigured to enable this function.
Alternatively, if you are using the hub in a network that uses the Internet Protocol (IP),
you manually configure the hub with an IP address using the hub console’s IP command.
See the IP command description in chapter 3, “Operation”, and appendix D, “Network
Addressing”, for more information on configuring a network-layer address on the hub.
When configured with an IP address, the hub can also send and respond to network-layer
test packets (ICMP Echo Request, or “Ping” packets).
Using Non-HP Network Management. To manage the HP EtherTwist Hub Plus and
Hub Plus/48 with a non-HP network management product, you must first obtain HP’s
Network Management Information Base (MIB) extensions. The HP MIB extensions are
available on request. Contact your HP-authorized LAN dealer or local HP sales office.
Introducing the HP EtherTwist Hub/12, Hub Plus, and Hub Plus/48 1-9
Upgrading the HP 28684B to an HP 28688B
To add network management capabilities, the HP 28684B EtherTwist Hub/12 can be
upgraded to an HP 28688B EtherTwist Hub Plus. The upgrade procedure involves a
software download to the HP 28684B Hub/12 using a unique password. The HP
EtherTwist Hub/12 Upgrade Kit, HP part number J2351A, is available from your nearest
Dealer or HP Sales Office. (One Upgrade Kit must be ordered for each HP 28684B Hub/12
to be upgraded.)
Once upgraded, the HP 28684B Hub/12 becomes an HP 28688B Hub Plus and includes the
following features:
Remote management capability from a network management station that
supports SNMP over IP or IPX.
Additional console commands:
–
–
–
–
IP configuration
BAck-up link configuration
PIng (network-layer ICMP Echo Request test)
PAssword (to set network management access control)
Network update capability for future firmware enhancements.
1-10 Introducing the HP EtherTwist Hub/12, Hub Plus, and Hub Plus/48
2
Installation
This chapter describes how to install and configure the HP 28684B EtherTwist Hub/12,
HP 28688B Hub Plus, and HP 28699A Hub Plus/48, and verify that they are operating
correctly.
Installation Summary
The steps to install the hubs are:
1.
2.
3.
4.
Mount the hub (in a rack, on a wall, or on a table).
Plug in the hub and verify its operation.
Connect the hub to devices and networks.
Customize the hub’s configuration if necessary (for example, because you want to
turn off the unused ports, or, for the HP 28688B and HP 28699A only, because the
hub will be managed remotely from a network management station on an IP
network).
The details for these steps are provided in the rest of this chapter.
Tools and equipment needed for mounting the hub in a rack or on the wall:
Phillips (cross-head) number 1 screwdriver (for rack or wall mounting)
four 5⁄8-inch number 12 wood screws or equivalent (for wall mounting only)
Installation 2-1
1. Mount the hub
1. Make sure the hub’s power cord is correct for your country’s ac power supply. Do
not plug the power cord into the power supply until the hub is mounted. (Note
that the hub does not have a power switch; the hub is powered on when the power
cord is plugged in.)
2. As described on the next page, mount the hub in a rack or on a wall by using the
mounting brackets, or place it on a table.
Before mounting the hub, plan its location and orientation relative to other devices and
equipment. Also consider management of the cabling you will be attaching and consider
access to the ports you will be using. In the example below, the hub is mounted in a rack
with other HP EtherTwist family devices and a cable guide unit. Order the
HP EtherTwist LAN Rack (HP 46298D) and the Cable Guide (HP 35199D). If you are
using a modular adapter on an EtherTwist hub, position that hub at least one rack unit
apart from any HP Fiber-Optic Hub Plus for easier port access.
Cable guide
HP network
devices; hubs, bridges,
etc.
Thin coaxial cable
backbone
Standard 19-inch telco
rack
2-2 Installation
Mounting the HP 28684B EtherTwist Hub/12 and HP 28688B Hub Plus
For Rack or Cabinet Mounting:
1. Using a Phillips or cross-head screwdriver, attach the mounting brackets to the
hub with 10-mm M4 screws (included in accessory kit). Note that the hub’s case
and the mounting brackets are designed to allow you to rack mount the hub with
either the back or the front facing out.
2. Position the hub in the rack or cabinet and slide it up or down until the rack holes
line up with the bracket holes. Then attach the hub to the rack with 5⁄8-inch
number 12-24 screws (included in the accessory kit). (Some cabinets require
number 10-32 screws instead, available as part number 2680-0302. Make sure
you have screws that fit your cabinet or rack before mounting the hub.)
Mounting bracket
Front facing out
10-mm M4 screws
Mounting bracket
5
⁄8-inch number 12-24
screws
Back facing out
Installation 2-3
For Wall Mounting: Using a Phillips or cross-head screwdriver, attach the mounting
brackets to the hub with 10-mm M4 screws (included in the accessories kit). Then attach
the hub to a wood surface (minimum 1⁄2-inch plywood or equivalent) with 5⁄8-inch number
12 wood screws or equivalent (not included).
Mounting bracket
10-mm M4 screws
Flat on wall
Mounting bracket
Straight out from wall
10-mm M4 screws
For Table Mounting: Attach the self-adhesive rubber feet to the bottom of the hub. Set
the hub on a table near a power source.
2-4 Installation
Mounting the HP 28699A Hub Plus/48
For Rack or Cabinet Mounting:
1. Using a Phillips (cross-head) screwdriver, attach the mounting brackets to the hub
with 10-mm M4 screws (included in accessory kit).
2. Position the hub in the rack or cabinet and slide it up or down until the rack holes
line up with the bracket holes. Then attach the hub to the rack with 5⁄8-inch
number 12-24 screws (included in accessory kit).
10-mm M4 screws
Mounting bracket
You can rack mount the hub with
either the back or the front facing
out.
5
⁄8-inch 12-24 screws
(Some cabinets require number 10-32 screws instead, available as p/n 2680-0302. Make
sure you have screws that fit your cabinet or rack before mounting the hub.)
Installation 2-5
For Wall Mounting: Using a Phillips (cross-head) screwdriver, attach the mounting
brackets to the hub with 10-mm M4 screws, included in the accessories kit with the hub.
Then attach the hub to a wood surface (minimum 1⁄2-inch plywood or equivalent) with
5⁄8-inch number 12 wood screws or equivalent (not included).
Mounting bracket
Flat
on wall
10-mm M4
screws
Straight out
from wall
For Table Mounting: Attach the self-adhesive rubber feet to the four corners of the
bottom of the hub. Set the hub on a table near a power source.
2-6 Installation
2. Plug in the hub and verify its operation
1. Plug the power cord into the hub’s power socket and into an ac power source. Note
that the hub does not have a power switch; the hub is powered on when the power
cord is plugged in.
The HP EtherTwist hubs have a power supply that automatically adjusts to any
ac power source that provides between 90 and 240 volts. No voltage range setting
is necessary.
2. Check the LEDs on the hub’s back panel.
When you plug in the hub, it executes a self-test and illuminates all the LEDs for
approximately ten seconds. At the end of the self-test you should see the following
LED pattern:
– The Power LED is ON.
– The Fault LED is OFF.
– Disregard the other LEDs until you have attached the LAN segments to the
network ports.
If the LED pattern is different, refer to “Diagnosing With the LEDs” in chapter 4,
“Troubleshooting”.
Installation 2-7
3. Connect the hub to devices and networks
Use the network ports (twisted-pair, AUI, and ThinLAN) to connect to computers, other
hubs or other network devices, or to a network backbone. Some examples follow showing
how to connect devices and networks to the hub’s network ports. Details of how to connect
your network cabling to the hub’s ports are included later in this chapter.
Connecting Computers
4-pair twisted-pair cable
25-pair cable to
cross-connect block
Hub
Hub
OR
50-pin connector attached
to twisted-pair port
Modular adapter attached
to twisted-pair port
Connecting to a Network Backbone
Transceiver
Hub
Hub
ThinLAN
coaxial cable
AUI port*
Coaxial or
fiber-optic
cable
BNC “T”
ThinLAN port
2-8 Installation
*Make sure the SQE test is disabled
on the attached transceiver.
Connecting Other Hubs
You can connect the hub to another HP EtherTwist twisted-pair hub using any of the
network ports. Some examples are shown below. Note that twisted-pair cabling may pass
through intermediate cross-connect blocks. See the HP EtherTwist Technical Reference
Guide (part number 5091-3237E) for information on network topologies.
Twisted-Pair Port to Twisted-Pair Port:
Modular adapters attached to
twisted-pair ports
HP
EtherTwist
hub
Twisted-pair cable
with Tx and Rx
pairs reversed*
HP
EtherTwist
hub
* Between hubs, Tx and Rx pairs must be reversed. You can use the HP 92214W
Crossover Cable with Inline Adapter to reverse the pairs. For more details and a wiring
diagram, see appendix A.
ThinLAN Port to ThinLAN Port:
ThinLAN cable
HP
EtherTwist
hub
HP
EtherTwist
hub
BNC “T” attached
to ThinLAN port
AUI Port to Twisted-Pair Port:
Twisted-pair cable
(Tx and Rx pairs
NOT reversed)
HP
EtherTwist
hub
HP EtherTwist
transceiver
attached to
AUI port
Twisted-pair
port with modular adapter
OR
50-pin connector
HP
EtherTwist
hub
Installation 2-9
Port Connections
Caution
Do not touch the connector pins of connectors or cables. Static discharge
may damage equipment.
Twisted-Pair Port
Using a 12-port modular adapter:
(One modular adapter is included with the
HP 28684B and HP 28688B. You can order
additional modular adapters, product
number HP 28638A.)
Screws
1. Remove the Velcro strap holder by
unscrewing and removing the two screws
that hold it to the back of the hub.
Velcro strap and holder
2. Plug the modular adapter into the
hub’s twisted-pair port and tighten
the two thumbscrews.
Be careful not to over tighten
the thumbscrews. Damage to
the hub’s case could result.
12-port
modular adapter
3. Attach the twisted-pair
network cables to the
modular adapter. Push the
cable’s 8-pin plug into the
jack until it clicks into place.
Thumb-screw
2-10 Installation
Twisted-pair port
Using a right-angle 50-pin connector:
1. Loosen the Velcro strap to make
room for the 50-pin connector.
50-pin
connector
Twisted-pair port
2. Slip the connector inside the strap
and plug it into the twisted-pair port.
3. Pull down on the Velcro strap end
to tighten it, then pull up and secure
the end to the strap.
Velcro strap
to cross-connect
block
Note: If you are using a mixture of modular adapters and right-angle 50-pin connectors on
a Hub Plus/48, position the modular adapters on ports to the left of the 50-pin connectors.
For information on twisted-pair cabling schemes using the 50-pin connector, see the
HP EtherTwist Technical Reference Guide (part number 5091-3237E).
Using a straight-out 50-pin connector:
1. Remove the Velcro strap holder by unscrewing and removing the two screws that
hold it to the back of the hub.
2. Attach standoffs (p/n 1252-3056). You can use the standoffs from an unused
console port or form the back of the modular adapter that came with your hub (HP
28684B or 28688B only). Be careful not to over tighten the stand-offs. Damage to
the hub’s case could result.
3. Plug in the connector and secure it to the standoffs.
Installation 2-11
ThinLAN Port
1. Attach a thin LAN cable section to one side of a BNC “T” connector.
2. Attach another thin LAN cable section or a 50-ohm terminator to the other side of
the “T” connector.
3. Attach the “T” connector to the ThinLAN port.
Thin LAN
cable
Thin LAN
cable
Thin LAN
cable
BNC “T”
mid-cable
attachment
ThinLAN port on hub
BNC “T”
50-ohm
terminator
end-of-cable
attachment
OR
ThinLAN port on hub
4. Fold the BNC “T” connector cover around the connection, and squeeze the surfaces
together around the edges.
BNC “T” connector cover
thin LAN cable
Note
Each thin LAN cable segment must be terminated with a 50-ohm
terminator at each end. In the illustration above showing the ThinLAN
port at the end of a cable segment, the 50-ohm terminator is attached to
one side of the BNC “T” connector.
2-12 Installation
AUI Port
Caution
Do not touch the hub connector pins or the cable connector pins. Static
discharge may damage the equipment.
1. Disable the SQE Test (signal
quality error, or “heartbeat”, test signal)
and Loopback Test options, if present
on the transceiver. See Note below.
AUI retainer
AUI port on hub
2. Slide the AUI retainer (included)
onto the connector posts on the
transceiver or AUI cable.
3. Plug the transceiver or AUI cable
into the AUI port on the hub and
secure it with the retainer’s screws.
Tighten the screws until they are snug;
do not over tighten them.
Transceiver or AUI
cable
4. Attach the network cable to the transceiver.
Note
Disable SQE Test on Transceiver.
Any transceiver used with this hub must allow disabling the SQE test.
An HP 28641A ThinMAU does not meet this requirement and cannot be
used. Instead use an HP 28641B ThinLAN Transceiver.
Similarly, an HP 30241A ThickMAU with date code D-3017 or earlier
cannot be used. (The date code is found on a small white sticker on the
body of the device. Lower numbers indicate an earlier manufacturing
date.) Instead, use an HP 30241A with date code F-3105 or later, and
follow the instructions that are included with the ThickMAU for disabling
SQE test.
Installation 2-13
4. Customize the hub’s configuration (if needed)
No changes to the hub’s default configuration are required for the hub to operate correctly.
The hubs each have a console interface for customizing the hub’s configuration, monitoring
its activity, and running diagnostics.
To configure the hub, first connect a terminal or PC running a terminal emulator, as
described under “Console Connection” below. Then, use the console interface to change
the desired hub configuration parameters. The commands that you can use to change the
hub’s configuration are listed and described later in this section under “Configuration
Commands”.
(The HP 28688B Hub Plus and HP 28699A Hub Plus/48 can also be configured over the
network from an HP network management station. See the network management product
documentation for more information.)
Console Connection
Connect a terminal to the hub’s console port directly or through modems, as described
below.
Connecting a Terminal Directly
1. Connect a terminal, or a PC emulating a terminal, to the console port using an
RS-232-C cable. (For pin-outs and recommended cables see appendix A, “Cables
and Connectors”.)
2. Switch on the terminal’s power (or switch on the PC’s power and start the
terminal emulation program). Configure the terminal for 8 bits per character, 1
stop bit, no parity, Xon/Xoff handshaking, and a baud rate of 9600, 2400, 1200, or
300.
3. Press RETURN several times for the prompt, =>. The baud rate for
communication between the hub and the terminal is set automatically when you
press RETURN.
2-14 Installation
Connecting a Modem and Terminal
1. Use a full-duplex, asynchronous (character-mode) modem only. The following
modems have been tested at their rated speeds:
– HP 37212B Support Link
– HP 35031A Support Link II
– HP 50759A Support Link
– Hayes 1200 Smartmodem
– Racal Vadic Maxell 2400VP (Hayes 2400 compatible)
– Black Box V.32 9600 Baud.
2. Configure the modem as described in appendix C, “Modem Configuration”.
3. Connect the modem to the console port using an RS-232-C modem cable. (For
pin-outs and recommended cables see appendix A, “Cables and Connectors”.)
4. At the remote site, connect the terminal (or PC emulating a terminal) to the
remote modem. Make sure the terminal and modems are functioning properly,
then establish the link between the terminal’s modem and the hub’s modem
according to the modem instructions.
5. Press RETURN several times for the prompt =>. The baud rate for
communication between the hub and the terminal is set automatically when you
press RETURN.
Installation 2-15
If You Have Trouble with a Terminal or Modem Connection
If you have connected a terminal or modem according to the previous instructions and you
do not get a prompt after you have pressed RETURN several times, then try the following
procedures in sequence until you get the prompt:
1. Connection Reset Procedure:
a. Detach, then reattach the console or modem cable from the hub.
b. Press RETURN several times for the prompt.
2. Cycle Power Procedure:
a. Cycle power on the hub by unplugging the power cord and plugging it in again.
b. When the power-on self-test is done, press RETURN several times for the
prompt.
3. Adjust Baud Rate Procedure:
a. Temporarily set the baud rate in the terminal’s own configuration to 2400.
b. Press RETURN several times for the prompt.
c. Set the hub’s baud rate to the desired rate (for example 9600) by using the
console’s Speed command (see “Console Commands” in chapter 3).
d. Set the terminal’s configuration to this new baud rate, and press RETURN
again for the prompt.
4. Test Console Port Procedure:
a. Detach the console cable from the hub. Attach the console port’s loopback
connector to the hub. (HP part no. 5062-3355––see appendix A, “Cables and
Connectors”.)
b. Cycle power on the hub by unplugging the power cord and plugging it in again.
As part of its power-on self-test the hub tests the console port.
c. If the test passes (the fault LED goes OFF), the console port should be
functional.
i. Remove the loopback connector and cycle power again.
ii. Connect the console cable to the hub. Press RETURN several times for the
prompt.
d. If the fault LED remains ON, the hub is faulty and must be replaced.
2-16 Installation
Configuration Commands
Several of the console commands allow you to customize the operation of your hub. They
are listed and described here.
Command Name
Command Function
Factory Preset
Value
Backup
(HP 28688B and
HP 28699A only)
Configures one of the hub’s ports for
dedicated use in a backup (redundant) link
to another hub.
IPconfig
(HP 28688B and
HP 28699A only)
Configures the hub to enable communication IP communications
with a network management station using
disabled.
the Internet Protocol (IP).
No backup link
configured.
Enables or disables linkbeat on specific
twisted-pair port.
Linkbeat enabled.
(You must disable
linkbeat on every
twisted-pair port
connected to a non10Base-T device.)
Port
Enables or disables specific hub ports.
All ports enabled.
Thinwatch disabled.
Thinwatch
Enables or disables Thinwatch. If
Thinwatch is enabled, the Fault LEDs and
ThinLAN port LED will flash if the
ThinLAN port becomes segmented.
Linkbeat
Note
Other console commands allow you to monitor the hub’s activity and to
diagnose hub and network problems. See chapter 3, “Operation”, for
console command details.
You can also receive information about a command at the console prompt
by entering HE (the Help command) followed by the first two characters of
the command, for example HE PO for help on the Port command.
Installation 2-17
3
Operation
The HP 28684B EtherTwist Hub/12, HP 28688B Hub Plus, and HP 28699A Hub Plus/48
are designed to operate unattended. A console interface is provided with these hubs if you
wish to customize their configuration, monitor their activity, or run diagnostics. (For the
HP 28688B and HP 28699A, you can also perform these and other functions with the HP
network management products from a network management station anywhere on the
network. See your HP network management product documentation for more
information.)
Starting the Console Session
To start the console session:
1. Make sure a console is connected and configured as described in “Console
Connection” in chapter 2 of this manual.
2. Press RETURN for the prompt. The console session prompt is =>. You may have
to press RETURN several times while the hub automatically senses the terminal’s
communication baud rate.
The console session starts with a display like the following (the actual version numbers
may be different, and the Hub Plus/48 has the label 48-port 10Base-T hub):
12-port 10Base-T hub
HW
A.01.00
ROM
A.01.02
EEPROM D.01.00
Enter HE for help.
Operation 3-1
Console Commands HP 28699A; console commands
Enter at least the first two letters of a command to execute it, such as HE for the Help
command. The Help command displays a screen like the following, listing all commands.
Note that the BAckup, IPconfig, PAssword, and PIng commands are not displayed for the
HP 28684B Hub/12.
The commands and their uses are described in the rest of the chapter.
HElp
To see a list and brief description of all available commands.
HElp <command>
To see the syntax and description of a specific console command. For the
<command> parameter, use the first two letters of the command you wish to see.
Example: HE ST
3-2 Operation
(This displays help for the Status command.)
BAckup (HP 28688B and HP 28699A Only)
To configure one of the hub’s ports for dedicated use in a backup (redundant)
link to another hub.
The HP EtherTwist Hub Plus and Hub Plus/48 allow you to use any two of their network
ports for a link to another hub in your network. The backup link normally carries no
traffic, but it is automatically activated if the primary link fails. Note that any of the ports
can be the backup port to any other port.
When you enter the Backup command, you are prompted for these values:
Backup Port
The port used for the backup link. Enter the port ID (see the Port
command description for the port IDs). Or, enter 0 if you wish to
remove an existing backup link configuration.
Primary Port
The port used for the primary link. Enter the port ID.
Remote Station
Address
The 12-digit hexadecimal station address of the hub at the remote
end of the critical link.
Seconds Between
Test Packets
How often you want the hub to send an IEEE 802.2 Test packet
to the remote hub over the primary link.
Consecutive Failures
The number of consecutive Test packet response failures that will
trigger activation of the backup link. For example, enter 5 to
activate the backup link on the fifth failure.
The hub monitors the primary link by sending IEEE 802.2 Test packets at the specified
frequency to the specified remote hub. If “n” consecutive Response packets are not
returned from the remote hub, the primary port is disabled and the backup port is enabled.
When the primary link is repaired, you must reenable the primary port. It is not
automatically reenabled. When the primary port is reenabled, the backup port is disabled
automatically and returned to backup mode. See “Reactivating the Primary Link” in
appendix E, “Backup Links”.
Appendix E contains more information on backup links, including requirements,
limitations, and sample topologies.
Operation 3-3
COunters
To display counters for each port, the global count for all ports, and the time
elapsed since they were last reset with the Reset command.
Total Packets
The total number of packets and fragments received.
Collisions
The number of times the port was involved in a collision. A single
collision will be counted by all ports involved, so the total collision
count may be less than the sum of the port counts.
CRC Errors
The number of packets with invalid Cyclic Redundancy Checksums
(CRCs). (The CRC is a calculated value used to check the validity of
each packet.)
Alignment Errors
The number of incorrectly aligned packets.
Giant Packets
The number of packets larger than 1518 bytes.
Broadcast Packets
The number of packets addressed to station address
FFFFFF-FFFFFF.
Note that counter values may be approximate under heavy network traffic consisting of
small packets. For the error counters, depending on the type of error, the number of the
associated port may not be known. In this situation, the error is recorded in the global
count only.
DIsconnect
To terminate the console session and reset the console port baud rate to be
automatically sensed. The command also disconnects the phone link if you accessed the
console using modems.
3-4 Operation
IPconfig (HP 28688B and HP 28699A Only)
To set IP configuration parameters on the hub. Use this command if you wish the
hub to be accessible using IP (the Internet Protocol). If either of the following is true, you
must set the IP configuration parameters on the hub:
The hub will be managed remotely with a network management product, such as
HP OpenView Hub Manager or HP OpenView Interconnect Manager, over an IP
network (a network operating system that uses IP communications).
The network cable segments attached to the hub will be tested using the IP “Ping”
test.
Note
Novell NetWare uses the IPX protocol. If you are using the hub on a
Novell NetWare network, no configuration of the hub is required for it to
communicate with a network management station that is also using the
IPX protocol. IPX is automatically enabled on the hub. The hub
determines its IPX address automatically from information received from
a router or file server that is running IPX on the network, and from its
own station address (also sometimes called the MAC address, physical
address, or Ethernet address).
See appendix D, “Network Addressing” for more information.
At the console interface prompt, enter IP and you will be prompted to enter values for the
parameters listed on the next page.
Operation 3-5
IP Address
The IP address of the hub, written in the format X.X.X.X.
Each number between the decimal points is a decimal number
between 0 and 255. Every IP address on a network must be
unique. The default is 0.0.0.0, which disables IP communications
on the hub.
Subnet Mask
The bit mask defining which portion of the IP address is the
subnet address, written in the format X.X.X.X. A default value is
automatically generated and depends on the class of IP address
that has been entered. See your network administrator for the
subnet mask used by all devices on your IP network.
Primary Default
Router
The IP address of the nearest IP router in your network. The
default value is 0.0.0.0. If no IP routers are in your network,
enter the address of a network management station, if any.
Backup Default
Router
The IP address of the router used in place of the primary default
router when it is inaccessible. The default value is 0.0.0.0. If
there is no backup router, or no primary default router, use
0.0.0.0.
Time To Live
The number of IP routers a packet is allowed to cross before the
packet is discarded. The default value is 32. Increase this value
if the hub will be sending IP packets to a destination that is more
than 32 routers away. The maximum is 255.
See your network administrator for these IP settings. See appendix D for information on
setting the IP address.
At the end of the process of changing the IP configuration, the hub will be reset. This
terminates the console session (and disconnects the phone line if using a modem) and
resets the console port baud rate to be automatically sensed. To restart the session, when
the reset process completes, press RETURN several times for the prompt.
3-6 Operation
LInkbeat <port> <ON/OFF>
To enable (set to ON) or disable (set to OFF) link beat on a port. The default
setting is enabled (ON). Disable link beat on any twisted-pair port that is not connected to
a Type 10Base-T device. Unused twisted-pair ports should have link beat enabled. The
<port> parameter can be:
a twisted-pair port number – from 1 to 12 for the Hub/12 and Hub Plus and from
1 to 12 preceded by a group number for the Hub Plus/48
a twisted-pair port group number – A, B, C, or D (Hub Plus/48 only)
ALL or AL for all twisted-pair ports
Example for the Hub/12 and Hub Plus: LI 1 OFF (This disables link beat for port 1.)
Example for the Hub Plus/48: LI A OFF (This disables link beat for all group A ports.)
PAssword (HP 28688B and HP 28699A Only)
To set or change the password on the hub. The password is used to prevent
unauthorized access of the hub from network management stations. The hub is
initially shipped without a password. Follow the prompts to enter a new password or to
change the existing password. You can use this command if you forget the password. To
remove an assigned password, enter the command, then press RETURN without entering
any characters at the password prompt.
PIng (HP 28688B and HP 28699A Only)
To run a test of the path between the hub and another device that responds to
IP packets. The hub sends Internet Control Message Protocol (ICMP) Echo Request
packets to another node with the specified IP address and waits for Echo Response packets
in return.
When you run the Ping command, you will be prompted for:
the IP address of the destination device (in the format X.X.X.X)
the number of packets to send
the timeout value (the number of seconds to wait for a response)
If any errors are reported during this test, there may be a fault on the path used during
the test or on the destination device. For more information about testing network links,
see chapter 4, “Troubleshooting”.
Operation 3-7
POrt <port> <ON/OFF>
To enable (set to ON) or disable (set to OFF) a hub port. The initial setting for all
ports is enabled (ON). To simplify network changes, unused ports need not be disabled.
You can use the Status command to check all the ports. The <port> parameter can be:
a twisted-pair port number – from 1 to 12 for the Hub/12 and Hub Plus and from
1 to 12 preceded by a group number for the Hub Plus/48 (for example B3 is port 3
in group B)
a twisted-pair port group number – A, B, C, or D (Hub Plus/48 only)
AUI or AU for the AUI port
THINLAN or TH for the ThinLAN port
ALL or AL (for all ports)
Example for the Hub/12 or Hub Plus: PO 1 OFF (This disables port 1.)
Example for the Hub Plus/48: PO A1 OFF (This disables port A1.)
REset
To run a hub self-test and reset the hub. This command also resets all the network
statistic counters, and the time since last reset to 0 (see the Counters command). The
current configuration is unchanged. The hub is not accessible from network management
software while it is being tested, but it continues to repeat data. If the hub is faulty, the
Fault LED will stay on. This command also terminates the console session (and
disconnects the phone line if using a modem) and resets the console port baud rate to be
automatically sensed. To restart the console session, reestablish the phone link (if used),
then press RETURN several times for the prompt.
SPeed <new speed>
To change the console port baud rate. Normally, the baud rate is automatically
sensed. Use this command to set the baud rate explicitly to 300, 1200, 2400, or 9600. You
will be prompted to set the terminal’s baud rate to the same speed and to press RETURN
several times for the prompt.
3-8 Operation
STatus <port group>
To display status information for the hub, including the time elapsed since the
last reset (see the Reset command), the hub’s station address, the Thinwatch
setting, and a table with the following port information:
For the Hub/12 and Hub Plus, do not specify a port group.
For the Hub Plus/48, the <port group> parameter is a letter A, B, C, or D. If no port group
is specified, all ports will be displayed.
Port
The port ID. (For the HP 28688B and HP 28699A, BKUP indicates
the port is configured as the backup link, PRI indicates the port is
the primary link).
Port Status
The status of each port:
ON means the port is enabled and is not auto-segmented.
OFF means the port has been explicitly disabled.
SEGMENTED means the port has been auto-segmented.
(See “Auto-Segmentation” in chapter 1.)
ON/REVERSED means that reversed wiring polarity on the receive
pair has been detected on a twisted-pair cable and the hub has
compensated.
Link Beat
The link beat status of each twisted-pair port:
OFF means link beat has been explicitly disabled.
NOT DETECTED means link beat is enabled but is not detected.
(Note: If a packet is received on a port with a missing link beat,
the port will be enabled for a short time. This may cause its port
LED to flash intermittently.) This field is blank if the port is
disabled.
Station Address
The station address of the device connected to each port, or:
NONE meaning an address has not yet been detected. A device
must transmit packets to be detected.
MULTIPLE meaning more than one address has been detected.
Operation 3-9
TEstlink
To run a test of the link between the hub and another IEEE 802.3 device.
Note
The destination device must be able to send an IEEE 802.2 Test response
packet upon receipt of an IEEE 802.2 Test command packet.
You will be prompted for the 12-digit hexadecimal station address (also called MAC
address, Ethernet address, or physical address) of the destination device. You will then be
prompted for the number of test packets to send.
If any errors are reported during this test, there may be a fault on the link being tested or
on the destination device. For more information about testing network links, see chapter
4, “Troubleshooting”.
THinwatch <ON/OFF>
To enable (set to ON) or disable (set to OFF) Thinwatch on the ThinLAN port.
With Thinwatch enabled, the Fault and ThinLAN port LEDs will flash whenever the
ThinLAN port is auto-segmented. (If you don’t enable Thinwatch, the LEDs won’t flash.)
Auto-segmentation occurs on the ThinLAN port when it is enabled but has no connector on
it, the connected segment is not properly terminated, or it experiences excessive collisions.
Segmentation of a twisted-pair port or the AUI port is always displayed on the
corresponding port LED and the Fault LEDs. See “Auto-Segmentation” in chapter 1.
The default setting is disabled to allow you to “bench test” the hub and not get a fault
indication. Enable Thinwatch if the ThinLAN port is being used; disable Thinwatch if it is
not being used.
Example: TH ON
3-10 Operation
(This enables Thinwatch.)
4
Troubleshooting
Some of the hub console commands are used for the troubleshooting instructions in this
chapter. See “Console Connection” in chapter 2 for details on connecting to the console
port. See chapter 3, “Operation”, for details on the console commands.
This chapter describes these topics:
basic troubleshooting tips
diagnosing with the LEDs
diagnostic tests:
– testing the hub only
– testing the hub’s ports and the links
– testing twisted-pair cabling
Basic Troubleshooting Tips
Make sure that you have a valid network topology. If you have trouble after a
recent change to the network, switch back to the previous topology. If you no
longer have trouble, the new topology is probably at fault. Topology faults may be
due to excessive cable lengths or excessive repeater delays between nodes. For
configuration guidelines, see the HP EtherTwist Technical Reference Guide
(part number 5091-3237E).
Make sure that the hub is plugged in and that cable connections are secure.
If the ThinLAN port is being used, make sure that the port is properly
terminated. See “ThinLAN Port Connection” in chapter 2.
Troubleshooting 4-1
Basic Troubleshooting Tips (continued)
If the ThinLAN port is not being used, make sure that Thinwatch is disabled.
(If Thinwatch is enabled on an unused ThinLAN port, the hub will operate but the
Fault LED will flash.) Use the console’s Thinwatch command.
Make sure link beat is set correctly on each twisted-pair port. See “Link Beat” in
chapter 1. (If link beat is set incorrectly, it may cause intermittent flashing of the
port’s LED on the hub and poor network performance for the device connected to
the port.) Use the console’s Status command to check link beat status and the
Linkbeat command to turn link beat on or off.
If a transceiver is connected to the AUI port of the hub, make sure its switches are
correctly set according to its instructions. Make sure the SQE test is disabled.
If the console port does not work, see “Console Connection” in chapter 2.
For the HP 28688B and HP 28699A only, if you are using IP communications,
make sure your IP configuration parameters are set correctly. Use the console’s
IPconfig command.
Check LEDs. For descriptions, see “Back of the Hub” in chapter 1. When power
is cycled, all LEDs should go ON momentarily and then go into their normal
operational states. If all LEDs do not go ON, an LED may be burned out, or the
hub is faulty and must be replaced. Whenever you suspect a burned-out LED,
cycle power by unplugging the hub and then plugging it in; then check the LEDs
immediately. When the hub is operating, LED patterns that indicate a hub or
network problem are shown in the table on the next page.
4-2 Troubleshooting
Diagnosing With the LEDs
LED patterns indicating problems
Power Collision
OFF
Diagnostic Tips
Fault
Port
*
*
Check power cord and power source. If OK,
replace the hub.
*
Very frequent collisions could indicate a
network fault or a cable not properly
terminated, or SQE test not disabled. If link
beat is not enabled on unused twisted-pair
ports, crosstalk may be causing the problem.
*
A hub hardware failure was detected during
self-test. Replace the hub.
*
*
Very
frequent,
or solidly
ON
*
*
ON
*
A port has been auto-segmented because of too
many collisions on a ThinLAN port not properly
Flashing Flashing
terminated or not connected. Check cable
terminations, connections, SQE test setting,
transceivers, and attached network devices.
*
*
*
*
OFF
Check cabling on the port indicated.
Use the Status console command to check if:
OFF or
– The port has been manually turned off.
flashing
In this case, turn the port back on.
intermit– Link beat is expected but not detected
tently
(link beat missing). In this case, be sure
on a
cable is plugged in and check link beat
port in
settings. See “Link Beat” in chapter 1.
use
Use the console’s Linkbeat command to
turn link beat on or off.
* This LED is not important for the diagnosis.
Troubleshooting 4-3
Diagnostic Tests
Testing the Hub Only
Choose one of the following procedures to test the hub’s internal circuitry. The first is the
most complete internal test. (The hub’s ports are not tested with the following procedures;
see the next page to test the ports.)
Cycle power on the hub by unplugging the power cord and then plugging it in.
This causes the hub to test itself. All LEDs should go ON momentarily before
returning to their operational states. If all do not go ON, an LED may be burned
out, or the hub is faulty. If the Fault LED on the front or back of the hub stays
ON, the hub is faulty and must be replaced.
Connect a console to the hub. Use the console’s Reset command, which causes the
hub to test itself. All LEDs should go ON momentarily before returning to their
operational states. If all do not go ON, an LED may be burned out, or the hub is
faulty. If the Fault LED on the front or back of the hub stays ON, the hub is
faulty and must be replaced. See chapter 3, “Operation”, for console command
details.
For the HP 28688B and HP 28699A only, use an HP network management
product to run a self-test. For instructions, see the network management
documentation.
4-4 Troubleshooting
Testing the Hub’s Ports and the Links
To test the hub’s ports and the attached network links, choose one of the following ways to
run a test between the hub and an addressable device connected at the remote end of each
of the cables you wish to test:
Use the console’s Testlink command to run a link test. This works with devices
able to send an IEEE 802.2 Test response packet upon receipt of a Test command
packet. You specify the remote device by its 12-digit hexadecimal station address.
See “Testlink” in chapter 3 for details.
For the HP 28688B and HP 28699A only, use the console’s Ping command to run a
network-layer test. This works with devices having an IP address and which are
able to respond to an ICMP echo request packet. You specify the remote device by
its IP address. See “Ping” in chapter 3 for details.
For the HP 28688B and HP 28699A only, use HP network management software
to test the link. For instructions, see the network management product’s
documentation.
If the test passes, the hub’s port, the network link, and the remote device are all working
properly. If testing the AUI port, this also tests a transceiver that is connected to the port.
If the test fails, you can test the hub using the procedures on the previous page. You
should also verify that the remote device is powered on and functioning properly, and that
the cable is good.
Testing Twisted-Pair Cabling
Twisted-pair cable must be compatible with the IEEE 802.3 Type 10Base-T standard.
Instruments are available that you can use to verify that your cable is compatible with
this standard. One such instrument is the HP 28687A Wire Test Instrument. HP also
offers a wire testing service. Contact your local HP sales office for more information.
Troubleshooting 4-5
A
Cables and Connectors
This appendix lists cables that have been tested and verified for use with the HP
EtherTwist Hubs. It also includes minimum pin-out information so, if you wish to use an
unlisted cable, you can verify that the cables used in your installation are correctly wired.
Note that each pin-out does not necessarily match the pin-out for the corresponding HP
cable, but cables manufactured to follow the minimum pin-out will function correctly.
Note
Incorrectly wired cabling is the most common cause of problems for LAN
communications. HP recommends that you work with a qualified LAN
cable installer for assistance with your cabling requirements.
These topics are discussed:
HP cables
Other standard cables
Twisted-pair cable/connector pin-outs
Thin LAN cable requirements
AUI cable
Console connector and cable pin-outs
Console port loopback connector
Cables and Connectors A-1
HP Cables
Cable
Function
Cable Type
Port Type
on
Terminal,
PC,
or Modem
HP Product Number
Connecting to the network:
Connecting
hub-to-hub
Twisted-pair
“crossover” cable
—
92214W (6-inch Crossover Cable)
Connecting
hub-to
computer
Unshielded
twisted-pair cable
—
92268A, B, C, D, or N (4-pair)
92214R, S, or T (25-pair)
—
92214U (0.5 meter),
includes a BNC “T” connector and
one 50-ohm terminator
—
92264D (1 meter)
92254A through H
(6–48 meters)
92254J (5 meters)
IEEE Type
Connecting hub10Base2 Thin
to-hub in a rack
coaxial cable
Connecting a
transceiver to
the AUI port *
AUI cable
Connecting to the console port:
Connect a
terminal or PC
to the console
port
Connect a
modem to the
console port
25-pin female 13242G† , 40242G†
RS-232-C
“Crossover” cable
25-pin male
9-pin male
9-pin female
(for HP 110)
13242H
24542G†
92221P†
“Straight-through” 25-pin female 13242M, 13242N, 17355M
RS-232-C modem
25-pin male 31391A
cable
* An AUI cable is not necessary with some transceivers such as the HP 28685A or
HP 28685B EtherTwist Transceivers, the HP 28641B ThinLAN Transceiver, and
the HP 28683A Fiber-Optic Transceiver. These transceivers can be attached directly
to the AUI port of a network device.
† For these cables, the signals DTR (pin 20) and RTS (pin 4) must be on, or high, on
your terminal or in your terminal emulator.
A-2 Cables and Connectors
Other Standard Cables
Cable Function
Port Type
on
Terminal,
PC,
or Modem
Standard Cable or
Cable Solution
Connecting to the console port:
Attach a null modem adapter† (Tandy Null Modem
Adapter No. 26-1496 has been tested) to the console
25-pin female
port. Then attach a straight-through modem cable to
the null modem adapter.
Connect a
terminal or PC to
the console port
with an
RS-232-C cable.* 9-pin male
Connect a
modem to the
console port
Use a Black Box PC/AT Serial Printer Cable
(EVNBPC has been tested).
OR
Attach a null modem adapter† (Tandy Null Modem
Adapter No. 26-1496 has been tested) to the console
port. Then attach a modem cable† (Black Box Cable
EVNBMC and Cablex PC Modem Cable have been
tested) to the null modem adapter.
25-pin female “Straight-through” RS-232-C modem cable (standard
or male port
cable)
* For these cables, the signals DTR (pin 20) and RTS (pin 4) must be on, or high, on
your terminal or in your terminal emulation program.
† The required minimum pin-out is listed in the section, “Console Connector and
Cable Pin-Outs”.
Cables and Connectors A-3
Twisted-Pair Cable/Connector Pin-Outs
Twisted-Pair Cable for Hub-to-Computer Connection
To connect PCs or other network devices to the hub, use a “straight-through” cable. The
twisted-pair wires must be twisted through the entire length of the cable. The wiring
sequence must conform to AT&T 258A (not USOC). See “Twisted-Pair Cable Pin
Assignments” later in this chapter for a listing of the signals used on each pin.
Straight-through cable
white/orange
orange/white
white/green
green/white
Note
Pins 1 and 2 must be wired to a twisted pair.
Pins 3 and 6 must be wired to a twisted pair.
Pins 4, 5, 7, and 8 are not used in this application, although they may be
wired in the cable.
A-4 Cables and Connectors
Twisted-Pair “Crossover” Cable for Hub-to-Hub Connection
For wiring between two hubs, the transmit and receive pairs must be reversed. The
twisted-pair wires must be twisted through the entire length of the cable. See
“Twisted-Pair Cable Pin Assignments” later in this chapter for a listing of the signals used
on each pin.
hub 2 end
hub 1 end
Crossover cable
white/orange
orange/white
white/green
green/white
Note
Pins 1 and 2 on the hub 1 end must be wired through a twisted pair to
pins 3 and 6 on the hub 2 end. Pins 3 and 6 on the hub 1 end must be
wired through a twisted pair to pins 1 and 2 on the hub 2 end.
Pins 4, 5, 7, and 8 are not used in this application, although they may be
wired in the cable.
crossover cable
A short crossover cable (like
the HP 92214W) can be used
to adapt a straight-through
twisted-pair cable for
“cascading” hubs through the
twisted-pair ports.
hub
straight-through
in-line adapter
straight-through
cable
hub
Cables and Connectors A-5
Twisted-Pair Cable Pin Assignments
Twisted-Pair Straight-Through Cable
Computer or
Transceiver End
Hub End
Signal
Pins
Pins
1
2
3
6
1
2
3
6
(receive +)
(receive –)
(transmit +)
(transmit –)
Signal
(transmit +)
(transmit –)
(receive +)
(receive –)
Twisted-Pair Crossover Cable
Hub 1-end
Signal
(receive +)
(receive –)
(transmit +)
(transmit –)
Hub 2-end
Pins
Pins
1
2
3
6
6
3
2
1
Signal
(transmit –)
(transmit +)
(receive –)
(receive +)
Thin LAN Cable Requirements
The thin coaxial cables used with the HP EtherTwist Hub/12, Hub Plus, and Hub Plus/48
must comply with the IEEE 802.3 Type 10Base2 requirements. Some RG-58 A/U or
RG-58 C/U cable meet these requirements.
The maximum length of a single thin coaxial cable segment is 185 meters.
A-6 Cables and Connectors
AUI Cable
Minimum Pin-Out
Transceiver
end
15-pin female
Hub end
15-pin male
2
3
4
5
6
9
10
12
13
2
3
4
5
6
9
10
12
13
Signal
Control In circuit A
Data Out circuit A
Data In circuit Shield (common drain)
Data In circuit A
Voltage Common
Control In circuit B
Data Out circuit B
Data In circuit B
Voltage Plus
For this connection, you can use:
HP 92264D (1-meter thin AUI
extension, pin 4 not connected)
HP 92254A through H (6-meter through
48-meter thick AUI cables)
HP 92254J (5-meter thin AUI cable,
pin 4 not connected)
Male
Connector
Female
Connector
Some longer cables may have all 15 pins wired.
See the IEEE 802.3 standards document for
definitions of the pins not shown here.
Cables and Connectors A-7
Console Connector and Cable Pin-Outs
The HP EtherTwist Hubs have a console port that automatically detects whether a
terminal or a modem is connected. No switch setting is required. Because of this function,
a standard “straight-through” cable can not be used when connecting a terminal directly.
For a terminal connection, you use a “crossover” cable (essentially a cable for connecting a
printer to a serial port), or a modem cable with a null modem adapter attached (which
provides the crossover function). For a modem connection, you can use a standard modem
cable.
This section provides pin assignment information for the cables you can use on the hub’s
console port.
Pin-Out for Hub’s Console Port Connector
PIN
US
CCITT
1
CHS GND
101
2
Tx
103
D1
3
Rx
104
D2
4
RTS
105
S2
5
CTS
106
M2
6
DSR
107
M1
7
GND
102
8
CD
109
M5
20
DTR
108
S1
M3
22
RI
125
23
SR
111
A-8 Cables and Connectors
DIN
RS-232-C “Crossover” Cable
(for Terminal/PC with 25-Pin Connector)
Minimum Pin-Out
Terminal/PC
end
25-pin male
Tx
Rx
GND
2
3
7
Hub end
25-pin male
2
3
7
5
6
8
22
23
Tx
Rx
GND
CTS
DSR
DCD
RI
DRS
RS-232-C “Crossover” Cable
(for Terminal/PC with 9-Pin Connector)
Minimum Pin-Out
Terminal/PC
end
9-pin female
Tx
Rx
GND
2
3
5
Hub end
25-pin male
2
3
7
5
6
8
22
23
Tx
Rx
GND
CTS
DSR
DCD
RI
DRS
Cables and Connectors A-9
RS-232-C Cable for HP 110
Minimum Pin-Out
HP110 end
9-pin male
Tx
Rx
GND
2
3
7
Hub end
25-pin male
2
3
7
5
6
8
22
23
Tx
Rx
GND
CTS
DSR
DCD
RI
DRS
Null-Modem Adapter
(use with a modem cable when connecting a terminal)
Minimum Pin-Out
Modem cable
end 25-pin
female
2
3
4
5
6
8
20
7
Hub end
25-pin
male
2
3
4
5
6
8
20
7
OR
4
5
4
5
DTR (pin 20) and RTS (pin 4) must be on, or high, on your terminal or in your terminal
emulation program.
A-10 Cables and Connectors
RS-232-C Modem Cable
Minimum Pin-Out
Modem end Hub end
25-pin male 25-pin male Signal
2
3
4
5
6
7
8
20
22
23
2
3
4
5
6
7
8
20
22
23
Tx
Rx
RTS
CTS
DSR
GND
CD OR DCD
DTR
RI
DRS – typically on V.24 (European) modems
Console Port Loopback Connector
The loopback connector shown below is useful for troubleshooting the console port on your
HP EtherTwist Hub/12, Hub Plus, and Hub Plus/48. This connector is included in the HP
Extended LAN Troubleshooting Kit, product number HP 28689B, or it can be purchased
separately. Contact your HP-authorized LAN dealer or your local HP sales office for
assistance.
HP part number 5062-3355.
The following pins are connected:
pin 2 to pin 3
pin 4 to pin 5 to pin 8
pin 6 to pin 20 to pin 22
pin 7 to pin 23
Cables and Connectors A-11
B
Specifications
HP 28684B Hub/12 and HP 28688B Hub Plus
Physical
Dimensions:
Weight:
42.5 cm by 23.5 cm by 4.4 cm
(16.8 in by 9.3 in by 1.7 in)
2.7 kg (6.0 lb)
Electrical
(The HP 28684B and HP 28688B hubs automatically adjust to any voltage between 90
and 240 volts and any frequency between 50 and 60 Hz.)
ac voltage:
100-120 volts
200-240 volts
Maximum current:
0.5 amps
0.5 amps
Frequency range:
50/60 Hz
50/60 Hz
Environmental
Temperature:
Relative humidity:
(non-condensing)
Maximum altitude:
Operating
Non-Operating
0°C to 55°C
(32°F to 131°F)
15% to 95%
at 40°C (104°F)
4.6 km (15,000 ft)
-40°C to 70°C
(-40°F to 158°F)
15% to 90%
at 65°C (149°F)
4.6 km (15,000 ft)
Specifications B-1
Cable Interfaces
The 50-pin twisted-pair port is compatible with the IEEE 802.3 Type 10Base-T
standard.
The ThinLAN port is compatible with the IEEE 802.3 Type 10Base2 standard.
The AUI port is compatible with IEEE 802.3 standards.
The RS-232-C console port conforms to V.22 bis.
Electromagnetic
Emissions
*FCC part 15 Class A
CISPR-22 Class A
*EN 55022 Class A
*VCCI Class I
Immunity
ESD
(in US, Canada, and Latic America)
(in Europe)
(in Japan)
*prEN 55101-2 (1991) / IEC 801-2 (3 kV CD, 8 kV AD)
(in Europe)
Radiated Emissions
*prEN 55024-3 (1991) / IEC 801-3 (draft) (3 V/m)
(in Europe)
* These specifications are legal requirements in the indicated countries.
Datacomm Declarations
United Kingdom
The HP 28684B and HP 28688B hubs are approved under Approval Number
NS/G/1234/J/100003 for indirect connection to public telecommunications systems within
the United Kingdom.
Sweden
Application and Declaration of Conformity to Swedish requirements has been filed.
Germany
Application for Certification and License approval have been filed.
B-2 Specifications
HP 28699A Hub Plus/48
Physical
Dimensions:
Weight:
42.5 cm by 23.5 cm by 8.9 cm
(16.8 in by 9.3 in by 3.5 in)
3.8 kg (8.8 lb)
Electrical
(The HP 28699A hub automatically adjusts to any voltage between 90 and 240 volts and
any frequency between 50 and 60 Hz.)
ac voltage:
100-120 volts
200-240 volts
Maximum current:
0.6 amps
0.5 amps
Frequency range:
50/60 Hz
50/60 Hz
Environmental
Temperature:
Relative humidity:
(non-condensing)
Maximum altitude:
Operating
Non-Operating
0°C to 55°C
(32°F to 131°F)
15% to 95%
at 40°C (104°F)
4.6 km (15,000 ft)
-40°C to 70°C
(-40°F to 158°F)
15% to 90%
at 65°C (149°F)
4.6 km (15,000 ft)
Cable Interfaces
The 50-pin twisted-pair port is compatible with the IEEE 802.3 Type 10Base-T
standard.
The ThinLAN port is compatible with the IEEE 802.3 Type 10Base2 standard.
The AUI port is compatible with IEEE 802.3 standards.
The RS-232-C console port conforms to V.22 bis.
Specifications B-3
Electromagnetic
Emissions
*FCC part 15 Class A
CISPR-22 Class A
*EN 55022 Class A
*VCCI Class I
Immunity
ESD
(in US, Canada, and Latic America)
(in Europe)
(in Japan)
*prEN 55101-2 (1991) / IEC 801-2 (3 kV CD, 8 kV AD)
(in Europe)
Radiated Emissions
*prEN 55024-3 (1991) / IEC 801-3 (draft) (3 V/m)
(in Europe)
* These specifications are legal requirements in the indicated countries.
Datacomm Declarations
United Kingdom
The HP 28699A hub is approved under Approval Number NS/G/1234/J/100003 for indirect
connection to public telecommunications systems within the United Kingdom.
Sweden
Application and Declaration of Conformity to Swedish requirements has been filed.
Germany
Application for Certification and License approval have been filed.
B-4 Specifications
C
Modem Configuration
HP 35031A Support Link II
At the hub
end:
At the user
end:
Configure SOFT OPTION 6 to 1.
Configure SOFT OPTION 15 to 2.
Configure SOFT OPTION 16 to 2.
Configure SOFT OPTION 20 to 2.
Configure SOFT OPTION 21 to 2.
Configure SOFT OPTION 16 to 2.
HP 50759A Support Link
At the hub
end:
For an 8-position switch, set switch 4 down, all others up.
For a 4-position switch, set switch 2 up, all others down.
At the user
end:
For an 8-position switch, set switches 3 and 8 down, all
others up. For a 4-position switch, set all switches down.
HP 37212B Support Link
At the hub
end:
Set switches 8, 9, 11, and 12 up (set to 1), all others down
(set to 0). AUTO ANS on the front should be pushed in.
At the user
end:
Set switches 8, 9, 11, and 12 up (set to 1), all others down
(set to 0).
Modem Configuration C-1
Black Box V.32 9600 Async.
At the hub
end:
Load the factory option set #1. Then make these changes:
– Data Rate Menu: change to 9600 uncoded
– Modem Parameters Menu: change to Forced Answer
– DTE Parameters Menu:
–
–
–
–
At the user
end:
set DTR State to Responds to DTR Change
set DSR State to DSR is Normal
set CTS State to CTS is Normal
set DCD State to DCD is Normal
Configure as at the hub end except:
– Modem Parameters Menu: change to Normal Originate
Hayes 1200 Smartmodem
(for both 8-and 10-switch units)
At the hub
end:
Set all switches up.
At the user
end:
Set switches 3 and 8 down, all others up.
Racal Vadic Maxell 2400 VP (Hayes 2400 Compatible)
At the hub
end:
Configure with a terminal or PC using the following
sequence:
at&f&c1&d2&s1q1*f0&wz
Depress the ANS button. The red light should go ON.
At the user
end:
Configure with a terminal or PC using the following
sequence:
at&f&c1&d2&s1*f0&wz
C-2 Modem Configuration
D
Network Addressing (HP 28688B and
HP 28699A Only)
The HP 28688B EtherTwist Hub Plus and the HP 28699A Hub Plus/48 can be managed
over the network by HP network management products, and any other network
management products that comply with the Simple Network Management Protocol
(SNMP) standard. The communication between the SNMP network management station
and the hub takes place using the network layer protocols, IPX for Novell networks, or IP
for TCP/IP networks.
Which protocol you use depends on the protocol being used by the network management
station. Additionally, if the network management station is on the other side of a router
from your hub, the protocol you run on both the hub and the network management station
depends on which protocol the router can handle.
The network layer communications require that the hub have a network layer address.
This appendix provides some background information on IPX and IP addressing.
IPX Addressing for Novell NetWare
The Novell NetWare network operating system uses a proprietary protocol called
Internetwork Packet Exchange (IPX). The IPX protocol firmware is always available on
the HP EtherTwist Hub Plus and Hub Plus/48; it becomes active when the hub gets an
IPX address. The IPX address consists of a network number and a device identification.
The address is automatically assigned to the hub as follows (no IPX configuration of the
hub is necessary):
The network number is automatically assigned by a router or file server on the
network that is running the IPX protocol.
The device identification is merely the hub’s station address (also known as the
MAC address, Ethernet address, or physical address). This address is a unique
12-digit hexadecimal number assigned to the hub at the factory.
Network Addressing D-1
IPX Addressing Notes:
Because the IPX address is assigned automatically, no IPX configuration is
necessary; no IPX configuration is provided on the hub console interface. By
default, the hub is ready to be managed by an SNMP network management
station that is configured for IPX communications.
If your hub is part of a network that is running IPX only, you do not need to
perform the IP configuration.
IP Addresses for IP and Non-IP Networks
If you have chosen to manage your hub with an SNMP/IP network manager, your hub
must be configured with an IP address. If your network will be connected with other
networks that use IP addresses, you must use assigned IP addresses. Otherwise, you can
build your own IP addressing scheme (described on the next page).
Using Assigned IP Addresses
Hewlett-Packard strongly recommends that if you intend to expand, integrate, or connect
your network to other networks, you use an assigned IP address. There is a formal
process to assign unique IP addresses to networks worldwide. DDN Network Information
Center in Menlo Park, California, is in charge of assigning IP addresses. Contact the DDN
Network Information Center by phone or mail. They will provide instructions and the
necessary documents to assign and register your IP addresses.
Telephone
in U.S. only:1-800-365-3642
worldwide:1-703-802-4535
FAX:1-703-802-8376
Mailing Address Government Systems, Inc.
Attn: Network Information Center
14200 Park Meadow Drive, Suite 200
Chantilly, VA 22021
D-2 Network Addressing
Building Your Own IP Addressing Scheme
If your network is isolated and will not be connected to any other networks that use IP
addressing, you can build your own IP addressing scheme. If you use your own addressing
scheme, be aware that any connection to another IP network could cause communication
problems on both networks. The IP addresses on the two networks must be compatible.
Each address must be unique.
The following documents have detailed descriptions on how to build your own IP
addressing scheme:
HP OpenView EtherTwist Network Management DOS Reference Guide
HP part number 5091-3635E
Internetworking With TCP/IP: Principles, Protocols, and Architecture
Author: Douglas E. Comer
Publisher: Prentice-Hall, Inc.
Example Addressing Scheme
On the next page is an example of a class C addressing scheme. Class C addresses allow
up to 254 devices to be configured. If you have 254 or fewer devices to be managed on your
network, you can use the addressing scheme shown below. If you have more than 254
devices to configure, see the referenced documents and use a class B addressing scheme.
Class B allows 65534 devices to be configured.
Network Addressing D-3
The IP address format is X.X.X.X, where each X is an integer between 1 and 255. The
integers are separated by decimal points. For a given network with its own class C
addressing scheme, the first three integers of each address must be the same. The fourth
integer must be unique for each addressed device. Do not use 0 or 255 in the fourth
position. They are reserved integers.
For three hubs and an HP network management station on the network, the class C
addresses might be:
management station
first hub
second hub
third hub
…
192.1.1.1
192.1.1.10
192.1.1.11
192.1.1.12
…
See “IPconfig” in chapter 3 for the IP configuration procedures and descriptions of the
parameters.
D-4 Network Addressing
E
Backup Links (HP 28688B and HP 28699A
Only)
Description
In some network configurations a critical link exists, for example between two workgroups
that regularly share or exchange data over the network. To maintain the integrity of such
a critical link, the HP EtherTwist Hub Plus and Hub Plus/48 offer a backup link feature.
A backup link is a separate cable run between two hubs that is automatically enabled if
the connection designated as the primary link fails.
802.2 test packets
“primary” link
hub A
“monitoring
hub”
802.2 response packets
hub B
“remote hub”
“backup” link
(normally inactive)
The hub on which the redundant link is configured (hub A in the illustration), is
responsible for monitoring the link. It sends IEEE 802.2 Test packets to the remote hub
(hub B in the illustration) and looks for response packets from that hub. If the response
packets fail to come back, the primary link is considered as having failed and the backup
link, which had not been carrying any traffic, is enabled automatically. If the primary link
does fail, it is automatically disabled until it can be repaired and reenabled.
When the primary link is repaired, you must reenable the primary port. It is not
reenabled automatically. When the primary port is enabled, the backup port is
automatically disabled and returned to backup mode. See “Reactivating the Primary
Link” later in this appendix.
Backup Links E-1
Limitations
Each hub can monitor a single backup link (only one backup link can be
configured on each hub). But, the hub may be at the remote end of one backup
link and at the monitoring end of a backup link to a different hub.
A given hub should be connected to the remote end of no more than two backup
links. If it is functioning as the remote hub in more than two backup links, it may
not be able to respond to the test packets fast enough when there is a high level of
data traffic on the network segments.
This limit may be exceeded by increasing the time between test packet
transmissions on the monitoring hubs. For all the backup links in which the
remote hub is involved, the time configured on the monitoring hubs for those links
should be increased by one second for each additional backup link beyond two
links. Add one to this count if the remote hub is also functioning as a primary
hub in a different link.
Additional Notes
Any port on the hub can be used for either the primary link or the backup link.
Any combination of media types can be used. For example, a thin coax link from
the ThinLAN port can act as a backup link to a twisted-pair link using one of the
hub’s twisted-pair ports. A transceiver attached to the hub’s AUI port can provide
a primary or backup link over any type medium (twisted-pair, coax, or fiber-optic
cable). (See “Sample Topologies” later in this appendix.)
The primary link and the backup link cabling should be run over different paths
(through different conduits, for example) to reduce the possibility that damage
will occur to both cables simultaneously.
E-2 Backup Links
Configuring a Backup Link
Configure the Monitoring Hub Only. All configuration of the backup link is
performed from the console on the hub that is responsible for monitoring the backup link.
On the remote hub, you only need to make sure the ports used in the primary and backup
links are both enabled.
Use the Console’s Backup Command. To configure this link, you use the Backup
command on the hub console interface. The command prompts you to identify the port
used for the backup link, the port used for the primary link, the station address of the hub
at the remote end of the link, how frequently (in seconds) test packets (used to check the
status of the primary link) should be sent to the remote hub, and how many consecutive
response failures will trigger activation of the backup link. The Backup command is
described in more detail in chapter 3, “Operation” under the section “Console Commands”.
Follow this Configuration/Installation Sequence. If a hub is installed in a network
that includes two connections to another hub, until one of the connections can be
configured as a backup link, a loop in the network exists causing some network
performance degradation. For this reason, it is better to configure the backup link on the
hub before the hub is installed in the network. It is best to follow these steps:
1. Attach a console to the hub’s console port and start a console session. (For
instructions see step 4, “Customize the hub’s configuration” in chapter 2.)
2. Use the Backup command (BA) to complete the backup link configuration. (See
the Backup command description in chapter 3, or enter HE BA at the console
prompt for online help on the Backup command).
3. Complete the network cable connections between the monitoring hub and the
remote hub. (For instructions, see “Port Connections” in chapter 2.)
4. Enable the primary port with the Port command (enter PO n ON where n is
the primary port’s ID). This step is necessary because, without the cables
connected, the test packets cannot be successfully sent and the backup port is
activated. Once you enable the primary port, it assumes the active role.
5. On the remote hub, make sure that the ports connected to both the primary and
backup links are enabled (PO n ON). On the monitoring hub, the status of the
primary and backup ports is controlled by the hub’s firmware; you do not need to
explicitly enable the monitoring hub’s ports.
Backup Links E-3
Identifying the Backup Link
The ports designated as the primary and backup ports are identified on the hub console’s
Status command screen by the words (PRI) and (BKUP), respectively, next to the port
numbers. HP network management products can also be used to identify the backup link.
See the HP network management product’s documentation for more information.
Indications of Backup Link Activation
When the primary link fails (“n” consecutive test packet responses were not received on
the primary port from the other hub), the backup link is automatically enabled. The effect
of this change is displayed on the monitoring hub’s LEDs and console interface. Activation
of the backup link does not change the status of any of the ports on the remote hub.
On the hub’s LEDs: The primary port LED goes off, and the backup port LED goes on.
On the hub console’s Status command screen: The status of the primary port
changes from ON to OFF, and the backup port changes from OFF to ON.
On HP network management products: Depending on the HP network management
product you have, you may be able to automatically monitor the status of the backup link
from the network management station. See your HP network management product
documentation for more information.
E-4 Backup Links
Reactivating the Primary Link
When the primary link is repaired, you can use any of the following methods to reenable
the primary port:
From the hub’s console, use the Port command, PO n ON where n is the
primary port’s ID.
Cycle power on the hub. This is useful if you do not have access to the hub’s
console interface (for example, because the hub is in a wiring closet and a console
is not connected).
From an HP network management station, reenable the port or reset the hub.
See the network management product documentation for details on how to enable
a port or reset the hub.
When the primary port is reenabled, the backup port is automatically disabled and
returned to backup mode.
Backup Links E-5
Sample Topologies
Following are two simple sample topologies that may give you some ideas on how a backup
link could be used in your network.
Sample 1: EtherTwist Hub-to-EtherTwist Hub
In this sample topology, the primary and backup links consist of twisted-pair cable
segments between an HP EtherTwist Hub Plus/48 and an HP EtherTwist Hub Plus.
Wiring Closet 1
Wiring Closet 2
HP
EtherTwist
Hub
HP
EtherTwist
Hub
HP
10:10 LAN
Bridge
HP
EtherTwist
Hub
to another network
HP
EtherTwist
Hub/48
HP
EtherTwist
Hub
primary link
backup link
E-6 Backup Links
Sample 2: Backup Link Using Alternative Medium
In this topology, the primary link consists of a twisted-pair cable between twisted-pair
ports on a Hub Plus/48 and a Hub Plus; the backup link is from AUI port to AUI port on
the two hubs. Depending on the type of transceivers used, the backup link could use thin
coax, fiber-optic cable, or even twisted-pair cable. Note that any of the network ports on
these hubs can function as a backup to any other port.
Wiring Closet 1
Wiring Closet 2
HP
EtherTwist
Hub
HP
EtherTwist
Hub
HP
EtherTwist
Hub
HP
10:10 LAN
Bridge
to another network
HP
EtherTwist
Hub/48
HP
EtherTwist
Hub
primary link (twisted-pair cable)
backup link (thin coax, fiber-optic, or twisted-pair cable)
Backup Links E-7
Safety Information
Safety Symbols
Documentation reference symbol. If the product is marked with this symbol, refer to the
product documentation to get more information about the product.
WARNING
A WARNING in the manual denotes a hazard that can cause injury or death.
CAUTION
A CAUTION in the manual denotes a hazard that can damage equipment.
Do not proceed beyond a WARNING or CAUTION notice until you have understood the
hazardous conditions and have taken appropriate steps.
Grounding
These are safety class I products and have protective earthing terminals. There must be an uninterruptible
safety earth ground from the main power source to the product’s input wiring terminals, power cord, or supplied
power cord set. Whenever it is likely that the protection has been impaired, disconnect the power cord until the
ground has been restored.
For LAN cable grounding:
If your LAN covers an area served by more than one power distribution system, be sure their safety
grounds are securely interconnected.
LAN cables may occasionally be subject to hazardous transient voltages (such as lightning or
disturbances in the electrical utilities power grid). Handle exposed metal components of the network
with caution.
Servicing
There are no user-serviceable parts inside these products. Any servicing, adjustment, maintenance, or repair
must be performed only by service-trained personnel.
These products do not have a power switch; they are powered on when the power cord is plugged in.
Safety Information 1
Informations concernant la sécurité
Symboles de sécurité
Symbole de référence à la documentation. Si le produit est marqué de ce symbole,
reportez-vous à la documentation du produit afin d’obtenir des informations plus
détaillées.
AVERTISSEMENT
Dans la documentation, un AVERTISSEMENT indique un danger susceptible
d’entraîner des dommages corporels ou la mort.
ATTENTION
Un texte de mise en garde intitulé ATTENTION indique un danger susceptible de
causer des dommages à l’équipement.
Ne continuez pas au-delà d’une rubrique AVERTISSEMENT ou ATTENTION
avant d’avoir bien compris les conditions présentant un danger et pris les mesures
appropriées.
Cet appareil est un produit de classe I et possède une borne de mise à la terre. La source d’alimentation principale
doit être munie d’une prise de terre de sécurité installée aux bornes du câblage d’entrée, sur le cordon
d’alimentation ou le cordon de raccordement fourni avec le produit. Lorsque cette protection semble avoir été
endommagée, débrancher le cordon d’alimentation jusqu’à ce que la mise à la terre ait été réparée.
Mise à la terre du câble de réseau local:
si votre réseau local s’étend sur une zone desservie par plus d’un système de distribution de puissance,
assurez-vous que les prises de terre de sécurité soient convenablement interconnectées.
Les câbles de réseaux locaux peuvent occasionnellement être soumis à des surtensions transitoires
dangereuses (telles que la foudre ou des perturbations dans le réseau d’alimentation public). Manipulez
les composants métalliques du réseau avec précautions.
Aucune pièce contenue à l’intérieur de ce produit ne peut être réparée par l’utilisateur. Tout dépannage, réglage,
entretien ou réparation devra être confié exclusivement à un personnel qualifié.
Cet appareil ne comporte pas de commutateur principal ; la mise sous tension est effectuée par branchement du
cordon d’alimentation.
2 Informations concernant la sécurité
Hinweise zur Sicherheit
Sicherheitssymbole
Symbol für Dokumentationsverweis. Wenn das Produkt mit diesem Symbol markiert ist,
schlagen Sie bitte in der Produktdokumentation nach, um mehr Informationen über das
Produkt zu erhalten.
VORSICHT
Eine VORSICHT in der Dokumentation symbolisiert eine Gefahr, die Verletzungen oder
sogar Todesfälle verursachen kann.
ACHTUNG
ACHTUNG in der Dokumentation symbolisiert eine Gefahr, die das Gerät beschädigen kann.
Fahren Sie nach dem Hinweis VORSICHT oder ACHTUNG erst fort, nachdem Sie den
Gefahrenzustand verstanden und die entsprechenden Maßnahmen ergriffen haben.
Dies ist ein Gerät der Sicherheitsklasse I und verfügt über einen schützenden Erdungsterminal. Der Betrieb des
Geräts erfordert eine ununterbrochene Sicherheitserdung von der Hauptstromquelle zu den
Geräteingabeterminals, den Netzkabeln oder dem mit Strom belieferten Netzkabelsatz voraus. Sobald Grund zur
Annahme besteht, daß der Schutz beeinträchtigt worden ist, das Netzkabel aus der Wandsteckdose herausziehen,
bis die Erdung wiederhergestellt ist.
Für LAN-Kabelerdung:
Wenn Ihr LAN ein Gebiet umfaßt, das von mehr als einem Stromverteilungssystem beliefert wird,
müssen Sie sich vergewissern, daß die Sicherheitserdungen fest untereinander verbunden sind.
LAN-Kabel können gelegentlich gefährlichen Übergangsspannungen ausgesetzt werden
(beispielsweise durch Blitz oder Störungen in dem Starkstromnetz des Elektrizitätswerks). Bei der
Handhabung exponierter Metallbestandteile des Netzwerkes Vorsicht walten lassen.
Dieses Gerät enthält innen keine durch den Benutzer zu wartenden Teile. Wartungs-, Anpassungs-,
Instandhaltungs- oder Reparaturarbeiten dürfen nur von geschultem Bedienungspersonal durchgeführt werden.
Dieses Gerät hat keinen Netzschalter; es wird beim Anschließen des Netzkabels eingeschaltet.
Hinweise zur Sicherheit 3
Considerazioni sulla sicurezza
Simboli di sicurezza
Simbolo di riferimento alla documentazione. Se il prodotto è contrassegnato da questo
simbolo, fare riferimento alla documentazione sul prodotto per ulteriori informazioni su di
esso.
PERICOLO
La dicitura PERICOLO denota un pericolo che può causare lesioni o morte.
ATTENZIONE La dicitura ATTENZIONE denota un pericolo che può danneggiare le attrezzature.
Non procedere oltre un avviso di PERICOLO o di ATTENZIONE prima di aver compreso le
condizioni di rischio e aver provveduto alle misure del caso.
Questo prodotto è omologato nella classe di sicurezza I ed ha un terminale protettivo di collegamento a terra.
Dev’essere installato un collegamento a terra di sicurezza, non interrompibile che vada dalla fonte
d’alimentazione principale ai terminali d’entrata, al cavo d’alimentazione oppure al set cavo d’alimentazione
fornito con il prodotto. Ogniqualvolta vi sia probabilità di danneggiamento della protezione, disinserite il cavo
d’alimentazione fino a quando il collegamento a terra non sia stato ripristinato.
Per la messa a terra dei cavi LAN:
se la vostra LAN copre un’area servita da più di un sistema di distribuzione elettrica, accertatevi che i
collegamenti a terra di sicurezza siano ben collegati fra loro;
i cavi LAN possono occasionalmente andare soggetti a pericolose tensioni transitorie (ad esempio,
provocate da lampi o disturbi nella griglia d’alimentazione della società elettrica); siate cauti nel
toccare parti esposte in metallo della rete.
Nessun componente di questo prodotto può essere riparato dall’utente. Qualsiasi lavoro di riparazione, messa a
punto, manutenzione o assistenza va effettuato esclusivamente da personale specializzato.
Questo apparato non possiede un commutatore principale; si mette scotto tensione all’inserirsi il cavo
d’alimentazione.
4 Considerazioni sulla sicurezza
Consideraciones sobre seguridad
Símbolos de seguridad
Símbolo de referencia a la documentación. Si el producto va marcado con este
símbolo, consultar la documentación del producto a fin de obtener mayor
información sobre el producto.
ADVERTENCIA
Una ADVERTENCIA en la documentación señala un riesgo que podría resultar en
lesiones o la muerte.
PRECAUCION
Una PRECAUCION en la documentación señala un riesgo que podría resultar en
averías al equipo.
No proseguir después de un símbolo de ADVERTENCIA o PRECAUCION hasta
no haber entendido las condiciones peligrosas y haber tomado las medidas
apropiadas.
Este aparato se enmarca dentro de la clase I de seguridad y se encuentra protegido por una borna de puesta a
tierra. Es preciso que exista una puesta a tierra continua desde la toma de alimentación eléctrica hasta las bornas
de los cables de entrada del aparato, el cable de alimentación o el juego de cable de alimentación suministrado. Si
existe la probabilidad de que la protección a tierra haya sufrido desperfectos, desenchufar el cable de alimentación
hasta haberse subsanado el problema.
Puesta a tierra del cable de la red local (LAN):
Si la LAN abarca un área cuyo suministro eléctrico proviene de más de una red de distribución de
electricidad, cerciorarse de que las puestas a tierra estén conectadas entre sí de modo seguro.
Es posible que los cables de la LAN se vean sometidos de vez en cuando a voltajes momentáneos que
entrañen peligro (rayos o alteraciones en la red de energía eléctrica). Manejar con precaución los
componentes de metal de la LAN que estén al descubierto.
Este aparato no contiene pieza alguna susceptible de reparación por parte del usuario. Todas las reparaciones,
ajustes o servicio de mantenimiento debe realizarlos solamente el técnico.
Este producto no tiene interruptor de potencia; se activa cuando se enchufa el cable de alimentación.
Consideraciones sobre seguridad 5
Safety Information
6 Safety Information
Regulatory Statements
FCC Statement (For U.S.A. Only)
Federal Communications Commission Radio Frequency Interference Statement
Warning: This equipment generates, uses, and can radiate radio frequency energy. If it is not installed and
used in accordance with the instruction manual, it may cause interference to radio communications. It has been
tested and found to comply with the limits for a Class A computing device pursuant to Part 15 of FCC Rules,
which are designed to provide reasonable protection against such interference when operated in a commercial
environment. Operation of this equipment in a residential area is likely to cause interference, in which case the
user at his own expense will be required to take whatever measures may be required to correct the interference.
If this equipment causes interference to radio reception (which can be determined by unplugging the power cord
from the equipment) try these measures: Re-orient the receiving antenna. Relocate the equipment with respect
to the receiver. Plug the equipment and receiver into different branch circuits. Consult your dealer or an
experienced technician for additional suggestions.
VCCI Class 1 (For Japan Only)
Regulatory Statements 1
Declaration of
Conformity
The following Declarations of Conformity for the HP 28684B,
HP 28688B, and HP 29699A comply with ISO/IEC Guide 22 and
EN 45014. The declarations identify the product, the
manufacturer’s name and address, and the applicable
specifications that are recognized in the European community.
2 Regulatory Statements
Regulatory Statements 3
4 Regulatory Statements
One-Year Limited Hardware Warranty
Hewlett-Packard warrants this computer hardware product against defects in materials
and workmanship for a period of one year from receipt by the end user. If HP receives
notice of such defects during the warranty period, HP will, at its option, either repair or
replace products that prove to be defective.
Should HP be unable to repair or replace the product within a reasonable amount of time,
Customer’s alternative exclusive remedy shall be a refund of the purchase price upon
return of the product.
Exclusions The above warranty shall not apply to defects resulting from: improper or
inadequate maintenance by customer; customer-supplied software or interfacing;
unauthorized modification or misuse; operation outside of the environmental specifications
for the product; or improper site preparation and maintenance.
Warranty Limitations HP makes no other warranty, either expressed or implied, with
respect to this product. HP specifically disclaims the implied warranties of
merchantability and fitness for a particular purpose. Some states or provinces do not
allow limitations on the duration of an implied warranty, so the above limitation or
exclusion might not apply to you. However, any implied warranty of merchantability or
fitness is limited to the one-year duration of this written warranty.
This warranty gives you specific legal rights, and you might also have other rights which
vary from state to state, or province to province.
Exclusive Remedies The remedies provided herein are Customer’s sole and exclusive
remedies. In no event shall HP be liable for any direct, indirect, special, incidental, or
consequential damages, whether based on contract, tort, or any other legal theory. Some
states or provinces do not allow the exclusion or limitation of incidental or consequential
damages, so the above limitation or exclusion might not apply to you.
Third-Party Products HP designed the hubs to operate with industry-standard
hardware and software products.
Warranty 1
HP has conducted limited testing with certain non-HP products to determine compatibility
with the hubs. Please contact your HP authorized LAN dealer or HP representative for
the current list of tested products.
HP relies in part upon information from the suppliers of non-HP products and makes no
warranty, expressed or implied, with respect to the operation of these products or their
compliance with worldwide regulatory requirements. HP advises customers to conduct
independent examination to determine suitable levels of compatibility for the customer’s
individual needs.
Gewährleistung
HP gewährleistet, daß die Geräte frei von Material- und Fabrikationsfehlern sind. Die
Gewährleistungsfrist beträgt ein Jahr ab Lieferung. Etwaige fehlerhafte Geräte werden
nach eigenem Ermessen repariert oder ersetzt.
Garantía
Esta pieza de hardware está garantizada por HP contra defectos de materiales o
manufactura por un período de un año a partir del momento en que el usuario la recibe.
Durante dicho período de garantía, HP o un distribuidor autorizado reparará o
reemplazará según su criterio, aquellos productos que resulten defectuosos.
Garantie
Hewlett-Packard garantit le matériel d’informatique personnelle contre tout défaut de
matière et de fabrication pour une période d’un an à compter de la réception du matériel
par l’utilisateur. Hewlett-Packard ou le distributeur agréé HP choisira de remplacer ou de
réparer tout produit défectueux.
Garanzia
La Hewlett-Packard garantisce i propri prodotti hardware per computer contro i difetti di
materiali e di fabbricazione per un periodo di 12 mesi dal giorno in cui li riceve l’utente
finale. Durante il periodo di garanzia, la Hewlett-Packard o un Rivenditore autorizzato
riparerà o sostituirà i prodotti che risultassero difettosi.
2 Warranty
Index
A
Accessories kit, 1-3
Alignment errors, 3-4
AUI ports, 1-1, 2-9
Auto-segmentation, 1-2, 1-7
B
BAckup command, 3-3
Backup default router, 3-6
Backup link, 1-2
Backup links, E-1
Backup port, 3-3
Baud rate, 2-14, 2-16
Broadcast packets, 3-4
C
Cable interfaces, B-2
Cables and connectors, A-1
Collision detection, 1-6
Collisions, 3-4
Configuration commands, 2-17
Connecting a console, 2-14
Connecting a modem and terminal, 2-15
Connecting a terminal directly, 2-14
Connecting computers, 2-8
Connecting other hubs, 2-9
connecting to a network backbone, 2-8
Connecting to devices and networks, 2-8
Connectors, A-1
Consecutive failures, 3-3
Console commands, 3-2
Console connection, 2-14
Console session, 3-1
Index-1
COunters command, 3-4
CRC errors, 3-4
D
Declaration of conformity, C-2
Diagnosing with the LEDs, 4-3
Diagnostic tests, 4-4
E
Echo request packet, 1-2
electromagnetic specifications, B-2, B-4
Errors, 3-4
Ethernet address, 3-5
F
Features, 1-1
Firmware enhancements, 1-2, 1-8
G
Giant packets, 3-4
H
HElp command, 3-2
How the hub works, 1-6
HP, 3-2
HP 28684B
accessories kit, 1-3
cable interfaces, B-2
cables and connectors, A-1
configuration commands, 2-17
connecting a modem and terminal, 2-15
connecting computers, 2-8
connecting to a network backbone, 2-8
connecting to devices and networks, 2-8
console commands, 3-2
diagnosing troubles, 4-3
diagnostic tests, 4-4
features, 1-1
Index-2
firmware enhancements, 1-2, 1-8
how it works, 1-6
included parts, 1-3
installation, 2-1
mounting, 2-1
network address, 1-9
operation, 3-1
ports, 1-1
power cord, 1-3
specifications, B-1
starting a console session, 3-1
station address, 1-2
status LEDs, 1-4
testing ports and links, 4-5
troubleshooting, 4-1
HP 28688B
accessories kit, 1-3
backup links, E-1
cable interfaces, B-2
cables and connectors, A-1
configuration commands, 2-17
connecting a modem and terminal, 2-15
connecting computers, 2-8
connecting to a network backbone, 2-8
connecting to devices and networks, 2-8
diagnosing troubles, 4-3
diagnostic tests, 4-4
features, 1-1
firmware enhancements, 1-2, 1-8
how it works, 1-6
included parts, 1-3
installation, 2-1
mounting, 2-1
network address, 1-9
network addressing, D-1
network management, 1-8
operation, 3-1
ports, 1-1
power cord, 1-3
remote management, 1-2
specifications, B-1
starting a console session, 3-1
station address, 1-2
status LEDs, 1-4
Index-3
troubleshooting, 4-1
HP 28699A
accessories kit, 1-3
backup links, E-1
cable interfaces, B-3
cables and connectors, A-1
configuration commands, 2-17
connecting a modem and terminal, 2-15
connecting computers, 2-8
connecting to a network backbone, 2-8
connecting to devices and networks, 2-8
diagnosing troubles, 4-3
diagnostic tests, 4-4
features, 1-1
firmware enhancements, 1-2, 1-8
how it works, 1-6
included parts, 1-3
installation, 2-1
mounting, 2-5
network address, 1-9
network addressing, D-1
network management, 1-8
operation, 3-1
ports, 1-1
power cord, 1-3
remote management, 1-2
specifications, B-3
starting a console session, 3-1
station address, 1-2
status LEDs, 1-4
troubleshooting, 4-1
I
ICMP, 3-7
IEEE 802.3 Type 10Base-T, 1-2
Included parts, 1-3
Installation, 2-1
IP address, 3-6
IP addresses, D-2
IPX, 3-5
IPX addressing, D-1
Index-4
L
LEDs, 1-2
LEDs, diagnosing with, 4-3
LEDs, status, 1-4
Link beat, 1-7
Linkbeat command, 3-7
M
MAC address, 3-5
Modems, C-1
Mounting brackets, 1-3
Mounting the hub, 2-1
N
Network address, 1-9
Network addressing, D-1
Network management, 1-8
Network management, non-HP, 1-9
Novell Netware, D-1
O
Operation, 3-1
P
Password command, 3-7
Physical address, 3-5
Ping, 1-2
Ping command, 3-7
POrt command, 3-8
Ports, 1-1
Ports, connections, 2-10
Ports, testing, 4-5
Power cord, 1-3
Primary default router, 3-6
Index-5
R
Regulatory statements, C-1 - C-4
Remote management, 1-2
Remote station address, 3-3
REset command, 3-8
RS-232-C console port, 1-1
S
Safety information, C-1
Self-test, 1-2
specifications
electromagnetic, B-2, B-4
SPeed command, 3-8
STatus command, 3-9
Status LEDs, 1-4
Subnet mask, 3-6
T
Test packets, 1-2, 3-3
Testing ports and links, 4-5
Testing twisted-pair cabling, 4-5
TEstlink command, 3-10
ThinLAN ports, 1-1, 2-9
THinwatch command, 3-10
Time to live, 3-6
Total packets, 3-4
Troubleshooting, 4-1
Twisted-pair cabling, testing, 4-5
Twisted-pair ports, 1-1, 2-9
W
Warranty, 1-1
Index-6
Regulatory Information
The product described in this document complies with specific international regulations. See the document
section entitled “Regulatory Statements” for the applicable regulatory information.
Informations concernant la réglementation
Le produit décrit dans le présent document satisfait à des normes internationales spécifiques. Pour plus de détails
sur les réglementations applicables, reportez-vous à la section «Regulatory Statements».
Informationen über Kontrollvorschriften
Das in diesem Dokument beschriebene Produkt erfüllt bestimmte internationale Kontrollvorschriften. Für
Informationen über die zutreffenden Kontrollvorschriften lesen Sie bitte das Kapitel mit der Überschrift
“Regulatory Statements”.
Informazioni sulla regolamentazione
Il prodotto descritto in questo documento è conforme alle specifiche normative internazionali. Vedere la sezione
del documento intitolata “Regulatory Statements” per le informazioni sulle normative competenti.
Informacin reglamentaria
El producto que se describe en este documento cumple con determinados reglamentos internacionales. En cuanto
a la información reglamentaria correspondiente, ver la sección del documento titulada “Regulatory Statements”.
Printed in U.S.A
5090-2692 E0692
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