Cisco Explorer 4700, Hardware Installation And Maintenance Manual

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Preparing for Installation 2-7
Preparing to Make Connections
Preparing to Make Connections
When viewed from the rear, the power cable and power switch appear on the right side of the router
chassis. The system console port, auxiliary (AUX) port, and network processor module ports appear
to the left of the power cable and switch. (See Figure 2-2.)
Figure 2-2 Router—Rear View Showing Slot Numbering and Interface Ports
Slot Numbering
The chassis contains slots for three network processor modules. These slots correspond to the three
slot numbers printed on the chassis front panel. (See Figure 1-1.) Slot numbers represent the order
in which the system scans the network processor modules. Network processor module location is not
slot-dependent. Any module can be moved to any other available slot location. For optimum heat
dissipation, use the center slot position, slot 2, for the FDDI module if one is present.
For information on how to remove and replace network processor modules, see the sections
“Removing Network Processor Modules” and “Replacing Network Processor Modules” in the
chapter “Maintaining and Upgrading the Router.“
Unit Numbering
Unit numbering allows the system to distinguish between two interfaces of the same type. As viewed
from the rear of the chassis, the unit numbering of the network processor modules increments from
zero counting from the right to left. The system assigns unit number addresses to these network
modules by starting with zero for each module interface type and numbering from right to left and
from bottom to top. The lowest unit number of that interface type is the module closest to the power
supply. (See Figure 2-2.) For example, the unit number addresses for the modules in Figure 2-2 are
as listed in Table 2-1.
Table 2-1 Unit Numbering for Dual Serial, Ethernet, and Token Ring Modules
Slot No. Interface Type Unit Address No.
1 Serial Port (Top)
Serial Port (Bottom) 1
0
2 Ethernet 0
3 Token Ring 0
Slot 3
10BaseT
port
Ethernet
port
Slot 2
Chassis
release screw
Ethernet module Token Ring module
Auxiliary port Console port
Token Ring port
Serial interface ports
Dual serial
module
Slot 1
Power On/off switch
H1033a