Black Box LGB408A-R2 User manual

Chapter
Order toll-free in the U.S.: Call 877-877-BBOX (outside
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24 hours a day, 7 days a week: Call 877-877-2269 or fax
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Customer
Support
Information
Provides (8) 10-/100-/1000-Mbps RJ-45
ports.
8-Port Gigabit Unmanaged Switch
LGB408A-R2

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Trademarks Used in this Manual
Trademarks Used in this Manual
Black Box and the Double Diamond logo are registered
trademarks of BB Technologies, Inc.
Mac is a registered trademark of Apple Computer, Inc.
Any other trademarks mentioned in this manual are
acknowledged to be the property of the trademark owners.

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FCC and IC RFI Statements
FEDERAL COMMUNICATIONS COMMISSION
AND INDUSTRY CANADA RADIO FREQUENCY
INTERFERENCE STATEMENTS
This equipment generates, uses, and can radiate radio-
frequency energy, and if not installed and used properly, that
is, in strict accordance with the manufacturer’s instructions, may
cause interference to radio communication. It has been tested
and found to comply with the limits for a Class A computing
device in accordance with the specifications in Subpart B of
Part 15 of FCC rules, which are designed to provide reasonable
protection against such interference when the equipment
is 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 necessary to correct
the interference.
Changes or modifications not expressly approved by the party
responsible for compliance could void the user’s authority to
operate the equipment.
This digital apparatus does not exceed the Class A limits for
radio noise emission from digital apparatus set out in the Radio
Interference Regulation of Industry Canada.
Le présent appareil numérique n’émet pas de bruits
radioélectriques dépassant les limites applicables aux appareils
numériques de classe A prescrites dans le Règlement sur le
brouillage radioélectrique publié par Industrie Canada.

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NOM Statement
Normas Oficiales Mexicanas (NOM)
Electrical Safety Statement
INSTRUCCIONES DE SEGURIDAD
1. Todas las instrucciones de seguridad y operación deberán
ser leídas antes de que el aparato eléctrico sea operado.
2. Las instrucciones de seguridad y operación deberán ser
guardadas para referencia futura.
3. Todas las advertencias en el aparato eléctrico y en sus
instrucciones de operación deben ser respetadas.
4. Todas las instrucciones de operación y uso deben ser
seguidas.
5. El aparato eléctrico no deberá ser usado cerca del agua—
por ejemplo, cerca de la tina de baño, lavabo, sótano
mojado o cerca de una alberca, etc.
6. El aparato eléctrico debe ser usado únicamente con
carritos o pedestales que sean recomendados por el
fabricante.
7. El aparato eléctrico debe ser montado a la pared o al
techo sólo como sea recomendado por el fabricante.
8. Servicio—El usuario no debe intentar dar servicio al
equipo eléctrico más allá a lo descrito en las instrucciones
de operación. Todo otro servicio deberá ser referido a
personal de servicio calificado.

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NOM Statement
9. El aparato eléctrico debe ser situado de tal manera que su
posición no interfiera su uso. La colocación del aparato
eléctrico sobre una cama, sofá, alfombra o superficie
similar puede bloquea la ventilación, no se debe colocar
en libreros o gabinetes que impidan el flujo de aire por los
orificios de ventilación.
10. El equipo eléctrico deber ser situado fuera del alcance de
fuentes de calor como radiadores, registros de calor,
estufas u otros aparatos (incluyendo amplificadores) que
producen calor.
11. El aparato eléctrico deberá ser connectado a una fuente
de poder sólo del tipo descrito en el instructivo de
operación, o como se indique en el aparato.
12. Precaución debe ser tomada de tal manera que la tierra
fisica y la polarización del equipo no sea eliminada.
13. Los cables de la fuente de poder deben ser guiados de tal
manera que no sean pisados ni pellizcados por objetos
colocados sobre o contra ellos, poniendo particular
atención a los contactos y receptáculos donde salen del
aparato.
14. El equipo eléctrico debe ser limpiado únicamente de
acuerdo a las recomendaciones del fabricante.
15. En caso de existir, una antena externa deberá ser
localizada lejos de las lineas de energia.
16. El cable de corriente deberá ser desconectado del cuando
el equipo no sea usado por un largo periodo de tiempo.
17. Cuidado debe ser tomado de tal manera que objectos
liquidos no sean derramados sobre la cubierta u orificios
de ventilación.

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NOM Statement
18. Servicio por personal calificado deberá ser provisto
cuando:
A: El cable de poder o el contacto ha sido dañado; u
B: Objectos han caído o líquido ha sido derramado dentro
del aparato; o
C: El aparato ha sido expuesto a la lluvia; o
D: El aparato parece no operar normalmente o muestra un
cambio en su desempeño; o
E: El aparato ha sido tirado o su cubierta ha sido dañada.

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Table of Contents
Table of Contents
1. Specifications........................................................................ 8
2. Overview ............................................................................. 9
2.1 Introduction ................................................................. 9
2.2 Features........................................................................ 9
2.3 What’s Included ......................................................... 10
2.4 Hardware Description ................................................ 10
2.4.1 Front Panel ........................................................ 10
2.4.2 Back Panel......................................................... 12
3. Installation ........................................................................... 13
3.1 Connecting the Switch to PCs, Servers, and Other
Network Devices ........................................................ 13
3.2 Connecting the Switch to a Switch or Hub................ 13
3.3 Application Diagram .................................................. 14
4. Operation ........................................................................... 16
Appendix. Troubleshooting..................................................... 17
A.1 Contacting Black Box ................................................. 17
A.2 Shipping and Packaging............................................. 17

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Chapter 1: Specifications
1. Specifications
Approvals — FCC Class A, CE
Buffer Memory — RAM: 3.5 MB per device
Filtering/Forwarding Rate — 10-Mbps ports: 14,880 pps,
100-Mbps ports: 148,800 pps,
1000-Mbps ports: 1,488,000 pps
Flow Control — Full-duplex mode: IEEE 802.3x;
Half-duplex mode: Backpressure
JUMBO Frames — Supports 9 KB
MAC Address — 8K MAC addresses
Network Transmission Media — 10BASE-T CAT3, 4,
or 5 UTP/STP; 100BASE-TX CAT5 UTP/STP;
1000BASE-T CAT5 UTP/STP
Standards Compliance — IEEE 802.3 10BASE-T; IEEE 802.3u
100BASE-TX and IEEE 802.3ab 1000BASE-T copper
over Ethernet
Connectors — (8) integrated RJ-45 ports (10-/100-/
1000-Mbps)
Indicators — (17) LEDs: (1) Power, (8) 1000M, (8) Link/Act.
Temperature Tolerance — Operating: 32 to 104° F
(0 to 40° C);
Storage: -4 to +194° F (-20 to +90° C)
Relative Humidity — 10–90%, noncondensing
Power — Input: 100–240 VAC, 50–60 Hz;
Consumption: 15 W (max.)
Size — 1.7"H x 4.8"W x 8.9"D (4.4 x 12.3 x 22.8 cm)
Weight — 2 lb. (0.9 kg)

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Chapter 2: Overview
2. Overview
2.1 Introduction
The Switch provides eight 10-/100-/1000-Mbps RJ-45 ports. It
was designed for easy installation and high performance in an
environment where traffic on the network and the number of
users increase continuously. With its Gigabit chip set, the 9"
Gigabit Ethernet Switch can fully support the highest speed even
when fully loaded and running in full-duplex mode.
The switch also provides automatic crossover detection function-
ality on each port. It’s easy to uplink to another switch without
crossover cable.
This quiet switch operates without a fan.
The compact rigid desktop size was specifically designed for
Remote Office and Branch Office (ROBO) and medium to large
workgroups. You can install the switch where space is limited. It
provides smooth network migration and easy upgrades to
network capacity. The 9" size can be rackmounted on a 10” or
19” cabinet.
2.2 Features
• Complies with the IEEE 802.3 Ethernet, IEEE 802.3u Fast
Ethernet and IEEE 802.3ab Gigabit Ethernet standards.
• Provides eight 10-/100-/1000-Mbps Gigabit switching ports.
• Performs full wire-speed switching with Head of Line (HOL)
blocking prevention.
• Provides non-blocking and non-head-of-line blocking full
wire-speed forwarding.
• Supports store-and-forward operation.
• Has embedded 3.5 MB SRAM for packet buffer.
• Supports 9 KB JUMBO frames.
• Provides 8sK MAC address entry.

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Chapter 2: Overview
• Supports broadcast storm filtering.
• All ports provide Auto-Negotiation and Auto-MDI/MDI-X
functions.
• Supports flow control: backpressure for half-duplex and IEEE
802.3x for full-duplex mode
• Includes (17) LEDs: (1) Power, (8) 1000M, and (8) Link/Act.
• Configurable to 10-Mbps full-/half-duplex, 100-Mbps full-/
half-duplex and 1000-Mbps full-/half-duplex for each port.
• 9” inch compact size, rackmountable to 10" and 19" with
bracket.
2.3 What’s Included
Your package should contain the following items. If anything is
missing or damaged, contact Black Box Technical Support at
724-746-5500 or [e-mail].
• (1) 8-Port Gigabit Unmanaged Switch
• (1) AC power cord
• (2) 19" rackmounting brackets
• This user’s manual
2.4 Hardware Description
2.4.1 Front Panel
Figure 2-1 shows the front panel of the switch. Table 2-1
describes its components.
1
4
2
3
Figure 2-1. Front panel.

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Chapter 2: Overview
Table 2-1. Front panel components.
Number Name Description
1Power LED Lights when power to
the unit is on.
2(8) 1000M
LEDs
On when port is
operating at 1000
Mbps. Off when port
is operating at 10 or
100 Mbps.
3(8) Link/Act.
LEDs
On when there is a
valid link to the
corresponding port.
Flashing when data is
activating.
4
(8) RJ-45
switching
ports
Link to 10BASE-T,
100BASE-TX, and
1000BASE-T devices.
Automatically sense
10/100/1000M speed
and negotiate full-/
half-duplex mode.
NOTE: For more information about the LED indicators, go to
Chapter 4, Operation.

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Chapter 2: Overview
2.4.2 Back Panel
Figure 2-2 shows the back panel of the switch. Table 2-2
describes its components.
5
Figure 2-2. Back panel.
Table 2-2. Back panel components.
Number Name Description
53-prong
receptacle
Insert 90–240-VAC,
50-/60-Hz power
supply cord here.

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Chapter 3: Installation
3. Installation
3.1 Connecting the Switch to PCs, Servers, and
Other Network Devices
Use straight-through twisted-pair cable (CAT5) to connect the
Switch to PCs, servers, and other network devices. See Figure
3-1.
8-Port Gigabit
Unmanaged Switch
(LGB408A-R2)
PC Mac®Server Workstation
Figure 3-1. Connecting to PCs, servers, and
other network devices.

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Chapter 3: Installation
3.2 Connecting the Switch to a Switch or a Hub
Use the straight-through twisted-pair cable to connect the
switch to another switch or hub on the uplink port.
Connected to Port 1,
uplink port on switch #2
Connected to Port 2
on switch #1
CATx cable
Figure 3-2. Connecting the switch to a switch or hub.

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Chapter 3: Installations
3.3 Application Diagram
Mac PC
Workstation PC PC
PC PC Server
Dual-Speed
Hub
Fast Ethernet
Switch
Server
Gigabit
Ethernet
Switch
8-Port Gigabit
Unmanaged Switch
(LGB408A)
Figure 3-3. Typical application.

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Chapter 4: Operation
4. Operation
Figure 4-1 shows the LEDs on the switch’s front panel. Table 4-1
describes their functions.
1
4
2
3
Figure 4-1. LEDs on front panel of switch.
Table 4-1. Front panel indicators.
Number LEDs Status Description
1(1) Power
LED ON Power is on
2
8 (1–8)
1000-Mbps
LEDs
ON Link is running at
1000 Mbps.
OFF Link is running at
10/100 Mbps.
38 (1–8)
Link/Act.
ON Link is established.
Flashing Data is activating.

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Appendix: Troubleshooting
Appendix. Troubleshooting
A.1 Contacting Black Box
If you determine that your 8-Port Gigabit Unmanaged Switch is
malfunctioning, do not attempt to alter or repair the unit. It
contains no user-serviceable parts. Contact Black Box Technical
Support at 724-746-5500 or [e-mail].
Before you do, make a record of the history of the problem. We
will be able to provide more efficient and accurate assistance if
you have a complete description, including:
• the nature and duration of the problem.
• when the problem occurs.
• the components involved in the problem.
• any particular application that, when used, appears to create
the problem or make it worse.
A.2 Shipping and Packaging
If you need to transport or ship your 8-Port Gigabit Unmanaged
Switch:
• Package it carefully. We recommend that you use the original
container.
• If you are returning the unit, make sure you include everything
you received with it. Before you ship for return or repair,
contact Black Box to get a Return Authorization (RA) number.

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NOTES

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NOTES

Chapter
Page 900
About Black Box
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LGB408A-R3 User Manual, version 2
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