Cisco XR 12406 - Manual (Page 143)

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Cisco XR 12406 Router Installation Guide
OL-13831-01
Chapter 4 Troubleshooting the Installation
Troubleshooting the Processor Subsystem
If you are unable to resolve the problem or if you determine that either the PEM
or power wiring is faulty, contact a service representative for assistance.
Troubleshooting the Processor Subsystem
The Cisco XR 12406 router processor subsystem consists of the RP, the line
cards, and the alarm cards. The RP and the line cards each have two processors.
One processor is the main processor; the other processor is a component in the
MBus module.
• The MBus module begins operation as soon as power is applied to the system.
The MBus module determines the type of card it is mounted on and whether
it should turn on the DC-DC converter.
• The RP MBus module turns on card power after a brief delay; the line card
MBus modules delay turning on power until they receive a command from the
RP.
A Cisco XR 12406 router requires that one RP be installed, or the system cannot
operate. A line card that is partially connected to the backplane will send
incomplete signals to the RP, which could cause the system to hang. If necessary,
you can troubleshoot individual line cards, but first ensure that the RP is installed
properly and the system software has initialized successfully.
A power-on self-test (POST) runs immediately at power-on to determine the
condition of the RP memory. Results are displayed in the alphanumeric LED
display as a pass/fail message.
Troubleshooting the RP
The LEDs on the route processor can help you to isolate a problem with the route
processor.
Figure 4-3 shows the RP alphanumeric LED displays.