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CONTENTS
ABOUT THIS GUIDE
Conventions 5
Related Documentation 5
SWITCH 7750 COMPONENTS
Switch Chassis 7
Switch Backplane 7
Fabric Module 8
Fabric 32 Submodules 12
I/O Modules 14
Power Module 33
Power Distribution 33
External PoE Power System 33
Fan Assembly 34
Switch 7750 Specifications 35
INSTALLING THE SWITCH 7750
Preparing to Install 37
General Site Requirements 38
Installation Checklist 39
Installing the Chassis 40
Installing the Cabling Rack 40
Installing a Module 41
Installing a Submodule 41
Connecting the Ground Wire 42
Connecting and Configuring Power 42
Installing the Fan Assembly 45
Installing Cables 45
Installing Cabling 47
Post-installation Checklist 48
CONFIGURINGTHE SWITCH 7750
Configuring the Switch 7750 and a Local Terminal 49
Setting Terminal Parameters 49
Booting the Switch 7750 52
4CONTENTS
MAINTAINING SOFTWARE
Upgrading Software 55
Lost Passwords 63
Using the BOOT Menu 63
TROUBLESHOOTING
Troubleshooting the Configuration 67
Troubleshooting Power 67
Troubleshooting the Fan 68
Troubleshooting the Modules 68
MAINTAINING HARDWARE
Replacing a Power Module 69
Replacing a Power Supply 70
Replacing I/O Modules 71
Replacing the Fan Assembly 71
OBTAINING SUPPORTFORYOUR SWITCH
Register Your Product to Gain Service Benefits 73
Purchase Value-Added Services 73
Troubleshoot Online 73
Access Software Downloads 73
Contact Us 74
Telephone Technical Support and Repair 74
SWITCH 7750 CABLES
Console Cable 77
AUX Cable 77
Electrical Port Connector 78
Optical Fiber Cable Connectors 79
ABOUT THIS GUIDE
This guide describes the 3Com® Switch 7750 and how to install hardware,
configure and boot software, and maintain software and hardware. This guide
also provides troubleshooting and support information for your switch.
This guide is intended for qualified Service personnel who are responsible for
configuring, using, and managing the switches. It assumes a working knowledge
of local area network (LAN) operations and familiarity with communication
protocols that are used to interconnect LANs.
Always download the Release Notes for your product from the 3Com World Wide
Web site and check for the latest updates to software and product documentation
http://www.3com.com.
at
ConventionsTa bl e 1 lists icon conventions that are used throughout this guide.
Related
Documentation
Ta bl e 1 Notice Icons
IconNotice TypeDescription
Information noteInformation that describes important features or
instructions.
CautionInformation that alerts you to potential loss of data
or potential damage to an application, system, or
device.
WarningInformation that alerts you to potential personal
injury.
The following manuals offer additional information necessary for managing your
Switch 7750:
command line interface (CLI) commands, that you require to manage your
Switch 7750.
■ Switch 7750 ConfigurationGuide— Describes how to configure your Switch
7750 using the supported protocols and CLI commands.
■ Switch 7750 Release Notes — Contains the latest information about your
product. If information in this guide differs from information in the release
notes, use the information in the Release Notes.
These documents are available in Adobe Acrobat Reader Portable Document
Format (PDF) on the 3Com World Wide Web site at
http://www.3com.com/.
6ABOUT THIS GUIDE
1
SWITCH 7750 COMPONENTS
The chapter describes the following Switch 7750 components:
■ Switch Chassis
■ Switch Backplane
■ Fabric Module
■ Fabric 32 Submodules
■ I/O Modules
■ Power Module
■ Power Distribution
■ External PoE Power System
■ Fan Assembly
■ Switch 7750 Specifications
Switch ChassisThe Switch 7750 is available with a 4-slot, 7-slot, or 8-slot chassis. Table 2 lists the
hardware features of each model.
Ta bl e 2 Hardware Features of the Switch 7750 Models
8-Slot Chassis
4-Slot Chassis
3C16894
Fabric slots112
I/O module slots366
Fan slot112
AC/DC Power module
slots
233
7-Slot Chassis
3C16895
AC 3C16896
DC 3C16897
Switch BackplaneThe Switch 7750 backplane is part of the integrated chassis and delivers
high-speed data transfer between the Fabric and I/O modules. The backplane
bandwidth capacity is 96 Gbps.
The backplane supports the following functions:
■ Interconnection of signals between modules
■ Provides communication channels
■ Hot swapping for modules
■ Automatic recognition of slots
■ Distribution of power and management of the power supply for the system
8CHAPTER 1: SWITCH 7750 COMPONENTS
1
2
3
45 6
7
8
9
3C16857
1234
56
7
Fabric ModuleThere are three Fabric modules for the Switch 7750:
■ Fabric 64 (3C16857 or 3C16857R)
■ Fabric 32 (3C16872)
■ PoE Fabric 96 (3C16886)
The Fabric 64 and Fabric 32 are not interchangeable. You can install the Fabric 32
only in a 4-slot chassis. You can install the Fabric 64 only in the 7-slot or 8-slot
chassis. You can install the PoE Fabric 96 in all three chassis.
The Fabric module is the core of Switch 7750 system. It has the following
functions:
■ Connects the I/O modules through the backplane and forwards Layer 2 and
Layer 3 data
■ Manages and calculates routing
■ Performs the switch’s software upgrade and system reset functions
■ Monitors system power and the fan frame
Figure 1 illustrates the front panel of the PoE Fabric 96.
Figure 1 PoE Fabric 96
3C16886
1 Compact Flash port
2 1000BASE-X-SFP ports
3 Console port
4 Ethernet port
5 Ethernet port LEDs
6 Fan LEDs
7 Power LEDs
8 I/O module LEDs
9 Reset button
Figure 2 illustrates the front panel of the Fabric 64.
Figure 2 Fabric 64
3C16857
1 Reset button
2 Console port
3 Ethernet port
4 Ethernet port LEDs
5 Fan LEDs
3C16872
1234567
8
6 Power module LEDs
7 I/O module LEDs
Figure 3 illustrates the front panel of the Fabric 32.
Figure 3 Fabric 32
3C16872
1 Submodule slot
2 Console port
3 Ethernet port
4 Ethernet port LEDs
5 Fan LEDs
6 Power LEDs
7 I/O module LEDs
8 Reset button
Fabric Module9
Ta bl e 3 lists Fabric specifications.
Ta bl e 3 Fabric Specifications
PoE Fabric 96
Item
(3C16886)
Bandwidth96 Gbps64 Gbps32 Gbps
CPUMPC8245MPC8260 200 Mhz
BootROM512 KB1 MB
SDRAM256 M256 MB
Flash32 MB16 MB
Submodule slot 1
Dimensions (L x W)366.7 mm x 340 mm (14.5 x 13.5 in)
External portsOne console port that supports local and remote dial-up configuration
management of the switch.
One 10BASE-T/100BASE-TX port for upgrade and network
management
One Compact Flash
port for storing log
and host version and
for online software
upgrades
Four 1000BASE-X-SFP
ports
Maximum power
80 W80 W70 W (with
consumption
Fabric 64 (3C16857
or 3C16857R)
Fabric 32 (3C16872)
submodule)
Submodule SlotThe submodule slot in the Fabric 32 offers extended Ethernet capacity using the
following submodules:
10CHAPTER 1: SWITCH 7750 COMPONENTS
■ 4-port 1000BASE-X-GBIC submodule
■ 4-port 10/100/1000BASE-T submodule
For more information on these submodules, see “Fabric 32 Submodules”on
page 12.
Fixed PortsThe Switch 7750 Fabric modules provide the following fixed ports:
■ Compact Flash (CF) Port
■ 1000BASE-X-SFP (PoE Fabric 96 only)
■ Console Port
■ Ethernet Port
Compact Flash (CF) Port
The Fabric module provides a CF port to accommodate a standard CF card, where
you can save logging information, host version information, alarming and other
diagnostic information. You can also use the CF port to upgrade software online.
1000BASE-X-SFP Ports
The PoE Fabric 96 provides four 1000 Mbps full-duplex SFP ports. Table 4 describes
the SFP cables for these ports.
Ta bl e 4 Cables for 1000BASE-T-SFP Modules
Maximum
SFP Module
Wavelength
ConnectorMatching Cable
1000BASE-SX-SFP850 nmLC50/125 µm
Central
transmission
distance
550 m (1804 ft.)
multimode
optical fiber
cable
62/125 µm
275 m (902 ft.)
multimode
optical fiber
cable
1000BASE-LX-SFP1310 nm9/125 µm single
1000BASE-LH-SFP30 km (19 mi.)
mode optical
fiber cable
10 km (6 mi.)
1000BASE-ZX-LR-SFP1550 nm40 km (25 mi.)
1000BASE-ZX-VR-SFP70 km (43 mi.)
1000BASE-T-FD-SFPRJ-45100 m (328 ft.)
Ta bl e 8 describes the LEDs of the SFP ports.
Ta bl e 5 SFP Port LEDs
LEDDescription
LINK/ACTOff — The line is not connected.
Green — The line is connected.
Green flashing — Data is being transmitted or received.
Fabric Module11
Console Port
The console port is connected to the configuration terminal using an RJ-45
connector. You can use the console port for system debugging, configuration,
maintenance, management, and loading application files.
The console port can also be connected to a modem for functions such as remote
system debugging, configuration, maintenance, and management. You can
configure the baud rate on the console port.
Ta bl e 6 lists console port specifications.
Ta bl e 6 Console Port Specifications
SpecificationDescription
Port connectorRJ-45
Port standardAsynchronous EIA/TIA-232
Baud rate9600 bps (by default)
Transmission distance15 m (45 ft)
ServicesConnects with character terminal
Connects with local or remote PC serial port and runs terminal
emulation on a PC (a pair of modems are required for a
remote connection)
Ethernet Port
The Ethernet port on the Fabric is connected to a computer using an RJ-45
connector. You can use the Ethernet port for system application downloading and
debugging. The Ethernet port can also be connected to devices such as a network
management workstation to manage the system remotely.
Ta bl e 7 lists Ethernet port specifications.
Ta bl e 7 Ethernet Port Specifications
SpecificationDescription
Port connectorRJ-45
Number of port(s)1
Port speed10 Mbps, half/full duplex
Cable and maximum transmission
distance
Port functionSwitch software upgrade and network management
100 Mbps, half/full duplex
MDI/MDIX auto sensing
Category-5 twisted pair for transmission within 100 m
(328 ft)
See “Electrical Port Connector” on page 78 for an illustration of the RJ-45
connector and MDI/MDI-X pinout details.
Ta bl e 8 describes the LEDs of the Ethernet port.
Ta bl e 8 Ethernet Port LEDs
LEDDescription
LINKOff — The line is not connected.
Green — The line is connected.
12CHAPTER 1: SWITCH 7750 COMPONENTS
Table 8 Ethernet Port LEDs (continued)
LEDDescription
ACTIVEGreen — No data is being transmitted or received.
Module LEDs The module LEDs show the status of the I/O modules, as described in Table 9.
Ta bl e 9 I/O Module LEDs
LEDStatus description
RUNGreen or off — The module failed or has not been inserted.
ALMOff — The module is working normally or has not been
Power LEDs PWR1, PWR2, and PWR3 LEDs show the status of the power modules, as
described in
Ta bl e 10 Power LEDs
Ta bl e 10.
Green flashing — Data is being transmitted or received.
Green flashing — The module is working normally.
inserted.
Green or green flashing — The module failed or is not
working normally.
LEDDescription
OKGreen — The corresponding power module is working
normally.
Off — The corresponding power module is not working or
has not been installed.
FAILGreen — The corresponding power module is not working.
Off — The corresponding power module works normally or
has not been installed.
Fan LEDFan LEDs show the status of the fan frame, as described in Table 11.
Ta bl e 11 Fan LEDs
LEDDescription
OKGreen — The fan is working normally.
Off — The fan is not working or has not been installed.
FAILGreen — The fan is not working.
Off — The fan is working normally or has not been installed.
Reset ButtonThe reset button resets the entire system.
Fabric 32 SubmodulesThe Fabric 32 provides a slot for one submodule. The Fabric 32 supports the
following submodules:
4-Port 1000BASE-X-GBIC
Submodule
■ 4-Port 1000BASE-X-GBIC Submodule (3C16874)
■ 4-Port 10/100/1000BASE-T Submodule (3C16873)
The 4-port 1000BASE-X-GBIC submodule provides four GE full-duplex Ethernet
GBIC ports.
Figure 4 illustrates the 4-port 1000BASE-X-GBIC submodule.
Fabric 32 Submodules13
12
3C16873
12
Figure 4 4-Port 1000BASE-X-GBIC Submodule
3C16874
Ethernet GBIC port
2 Ethernet GBIC port LED
Ta bl e 12 describes the 4-port 1000BASE-X-GBIC submodule LEDs.
Ta bl e 12 4-Port 1000BASE-X-GBIC Submodule LEDs
LEDDescription
LINK/ACTGreen — The link is operating normally.
Off — The link is not operating.
Green flashing — Data is being transmitted or received.
Ta bl e 13 lists the specifications for each of the 4-port 1000BASE-X-GBIC
submodule.
4-Port
10/100/1000BASE-T
Submodule
Ta bl e 13 4-Port 1000BASE-X-GBIC Submodule Specifications
Max.
Optional GBIC
Module
1000BASE-SX-MM
(3CGBIC91)
1000BASE-LX-SM-IR
(3CGBIC92)
1000BASE-LX-SM
(3CGBIC97)
Central
Wavelength
850 nmSC50/125 µm
1310 nmSC9/125 µm
1550 nmSC9/125 µm
Connector
Type
Interface Fiber
Specifications
multi-mode fiber
62.5/125 µm
Multi-mode fiber
Single-mode fiber
Single-mode fiber
Transmission
Distance
500 m (1640 ft)
220 m (722 ft)
10 km (6 mi)
40 km (25 mi)
70 km (43.5 mi)
The 4-Port 10/100/1000BASE-T submodule provides four 10/100/1000 Mbps
auto-negotiation service ports.
Figure 5 illustrates the 4-port 10/100/1000BASE-T submodule.
Figure 5 4-Port 10/100/1000BASE-T Submodule
3C16873
1 Ethernet port
2 Ethernet port LEDs
14CHAPTER 1: SWITCH 7750 COMPONENTS
Ta bl e 14 describes the 4-port 10/100/1000BASE-T submodule LEDs.
Ta bl e 14 4-Port 10/100/1000BASE-T Submodule LEDs
LEDDescription
LINKOff — The link is not operating.
ACTOff — No data is being transmitted or received.
Ta bl e 15 lists specifications of the 4-port 10/100/1000BASE-T submodule.
Ta bl e 15 4-Port 10/100/1000BASE-T Submodule Specifications
SpecificationDescription
Connector typeRJ-45
Number of ports4
Port speed1000 Mbps full duplex
Cable and maximum
transmission distance
On — The link is operating normally.
Green flashing — Data is being transmitted or received.
The 48-port 10/100/1000BASE-T PoE module provides 48 10/100/1000 Mbps
auto-sensing Ethernet ports that provide a remote power supply to powered
devices.
Figure 12illustrates the 48-port 10/100/1000BASE-T PoE module.
Figure 8 48-port 10/100/1000BASE-T PoE Module
3C16890
Figure 13 illustrates the front panel and LEDs of the 48-port 10/100/1000BASE-T
PoE module.
Figure 9 Front Panel of the 48-port 10/100/1000BASE-T PoE Module
3C16890
1 Ethernet port
2 Ethernet port LED
I/O Modules17
Ta bl e 22 describes the 48-port 10/100/1000BASE-T PoE module LEDs.
Ta bl e 18 48-port 10/100/1000BASE-T PoE Module LED
LEDDescription
LINK/ACTGreen — The port is connected.
Off — The port is not connected.
Green flashing — Data is being transmitted or received.
Ta bl e 23 describes the specifications of the 48-port 10/100/1000BASE-T PoE
module.
Ta bl e 19 Specifications for the 48-port 10/100/1000BASE-T PoE Module
SpecificationDescription
CPUMPC8241
BootROM512 KB
SDRAM128 M
Dimensions (L X W) 366.7 x 340 mm (14.4 x 13.4 in.)
Maximum power consumption70 W
ConnectorRJ-45
Number of ports48
Port transmission speed10/100/1000 Mbps half-/full-duplex
Cables and maximum
transmission distance
ComplianceIEEE802.3ab
MDI/MDIX auto-sensing
Category 5 twisted pair with a maximum distance of 100 m
(328 ft.)
Ta bl e 26 lists the cables for the 48-port 100BASE-X (SFP) ports
Ta bl e 26 Cables for the 48-port 100BASE-X SFP Module
Central
wave-
SFP module
100BASE-FX-MM-SFP 1310nmLCmultimode optical fiber
100BASE-FX-SM-SFP1310nm15 km (9.3 mi)
100BASE-FX-SM-LR-SFP1310nm9/125 µm single mode
100BASE-FX-SM-VR-SFP1550nm70km (43 mi)
lengthConnector Matching cable
cable
optical fiber cable
Maximum
transmission
distance
2 km (1.2 mi)
40 km (24.9 mi)
The 24-port 100BASE-FX MMF FE module provides 24 100 Mbps multi-mode
Ethernet optical port service channels.
Figure 16 illustrates the 24-port 100BASE-FX MMF FE module.
22CHAPTER 1: SWITCH 7750 COMPONENTS
1
2
Figure 16 24-Port 100BASE-FX MMF FE Module
Each 100 Mbps optical port has a green LED, as shown in Figure 17.
Figure 17 Front Panel of the 24-Port 100BASE-FX MMF FE Module
1 Ethernet port
2 Ethernet port LED
Ta bl e 27 describes the status of the 24-port 100BASE-FX MMF FE module LEDs.
Ta bl e 27 24-Port 100BASE-FX MMF FE Module LEDs
LED Description
LINK/ACTGreen — The port is connected.
Off — The port is not connected.
Green flashing — Data is being transmitted or received.
The 24-port 100BASE-FX MMF FE module requires a 62.5/125 µm multi-mode
optical fiber cable with an MT-RJ connector and a central wavelength of 1300 nm.
Ta bl e 28 describes the specifications of the 24-port 100BASE-FX MMF FE module.
Ta bl e 28 Specifications for the 24-Port 100BASE-FX MMF FE Module
SpecificationDescription
CPUMPC850
BootROM512 KB
SDRAM64 MB
Dimensions (L x W) 366.7 x 340 mm (14.5 x 13.4 in)
Maximum power
consumption
Connector typeMT-RJ
Number of ports24
Port transmission speed100 Mbps, full-duplex
55 W
I/O Modules23
3C16863
12
Table 28 Specifications for the 24-Port 100BASE-FX MMF FE Module (continued)
SpecificationDescription
Cables and maximum
transmission distance
ComplianceIEEE 802.3
62.5/125 µm multi-mode optical fiber up to 2 km (1.3 mi)
IEEE 802.3i
IEEE 802.3u
IEEE 802.3x
20-Port
10/100/1000BASE-T
Module
The 20-Port 10/100/1000BASE-T module provides 20 10/100/1000BASE-T
auto-sensing Ethernet ports.
Figure 18 illustrates the 20-Port 10/100/1000BASE-T Module.
Figure 18 20-Port 10/100/1000BASE-T Module
Figure 19 illustrates the front panel of the 20-port 10/100/1000BASE-T module.
Figure 19 Front Panel of the 20-Port 10/100/1000BASE-T Module
3C16863
1 Ethernet port
2 Ethernet port LED
Ta bl e 29 describes the 20-port 10/100/1000BASE-T module LEDs.
Ta bl e 29 20-Port 10/100/1000BASE-T Module LEDs
LEDDescription
LINK/ACTOff — The port is not operating.
On — The port is operating.
Green flashing — The port is transmitting or receiving data
24CHAPTER 1: SWITCH 7750 COMPONENTS
3C168623C16862
12
Ta bl e 30 lists specifications of the 20-port 10/100/1000BASE-T module.
Ta bl e 30 Specifications for the 20-Port 10/100/1000BASE-T Module