Troubleshooting PREs

This section describes how to troubleshoot Performance Routing Engines (PREs). It provides information on troubleshooting PRE fault states, the management Ethernet port, and the serial port.

The PRE provides the IP routing and forwarding functionality in the Cisco 10000. Thus, in a non-redundant PRE configuration, a PRE failure is a system failure. A redundant PRE configuration is recommended.

If the PRE fails, the yellow PRE STATUS LED lights. You can try rebooting the Cisco 10000, moving the card to a different PRE slot, or replacing the PRE with another one. In any event, you should capture any error messages that appear on the console, as well as the state of the PRE LEDs and alphanumeric display. Then you should contact the Cisco Technical Assistance Center (TAC).

Figure 3-1 describes the LED indicators on the PRE faceplate. Use these descriptions to verify the operation of the PRE.

Figure 3-1: PRE Faceplate and LEDs

Table 3-1 lists the PRE fault indications and recommended actions. The information contained in the table is based on the assumption that you have a nonredundant configuration.

Table 3-1: PRE Module Fault Indications and Recommended Action

Fault Steps to Take

STATUS LED is not lit

1. Check LEDs on other modules and cards. If none are lit, refer to Table 2-1 or Table 2-3 depending upon the PEM type in your chassis.

2. If LEDs on other modules and cards are lit, remove the card from its slot and check for bent or broken pins on the backplane. Return the card to its slot and screw it firmly into place.

3. Replace the card.

4. If the problem persists, contact the Cisco TAC.

FAIL LED is yellow, indicating that the PRE failed

1. Reinsert the PRE.

2. Insert a new PRE.

3. If the problem persists, contact the Cisco TAC.

The PRE initializes, but you cannot establish a console connection

1. Ensure that the terminal settings are properly set.

2. If you still cannot connect, check the console cable. Is it firmly connected? Is it the correct type of cable with proper connectors?

3. If the cable checks out and you cannot establish a console or Telnet session, reinsert the PRE module. If the problem persists, replace the PRE.

4. Enter show log to review console messages recorded in the system log.

Card cannot be fully inserted into its slot

Make sure that you are using slot 0A or 0B for the PRE module.

An alarm LED is lit

1. Enter the show facility-alarm status command and examine the output to determine which system component raised the alarm.

2. Troubleshoot using a procedure appropriate to the module or FRU responsible for the alarm. Refer to the following sections for information on interpreting alarms:

OC-12 POS Line Card Alarms and Error Messages

Channelized T3 (CT3) Line Card Alarms and Error Messages

Ethernet Connection Problems

If the management Ethernet connection on the Cisco 10000 PRE fails to work properly, and the corresponding Link LED is not lit (steady green)

Visually check that an Ethernet cable is connected to the correct Ethernet port on the Cisco 10000.
Verify that you are using the correct type of cable for a 100BaseT Ethernet.
Check to see if the cable is bad or broken.
Make sure the PRE module booted up properly by checking the Status LED on its faceplate. This LED should be steady green. If necessary, remove and reinsert the module and boot it up again.

If the Link LED is lit (steady green), but the Ethernet port is not working properly, make sure that the port in question is configured properly and is not administratively shut down. If you have a working console connection, perform the following steps:

Step 1 At the switch prompt, enter show interface fastethernet0/0/0. If the port is administratively down, enter these commands to enable it:

c10000# configure terminal
Enter configuration commands, one per line. End with CNTL/Z.
c10000(config)#interface fastethernet0/0/0
c10000(config-if)# no shut
c10000(config-if)# exit
c10000(config)# exit
c10000#

Step 2 Check that the Ethernet port in question is assigned a valid IP address.

For more information about configuring Ethernet ports, refer to the Cisco 10000 ESR Software Configuration Guide.

If the cable, connections, power, and configuration all check out, and you still cannot connect to the Ethernet port on the module, replace the module in question. If the problem persists, contact the Cisco TAC for further assistance. Refer to the "Obtaining Technical Assistance" section for instructions on contacting the Cisco TAC.

Console Port Serial Connection Problems

If the console screen connected to a Cisco 10000 console port appears frozen or fails to work properly

Refer to the "Cisco 10000 System Startup Sequence" section. If the display stops responding during this process, there is no console output.
Check the console cable and make sure it is properly connected to the correct console port on the Cisco 10000 system at one end and to your terminal equipment or terminal server at the other end.
Verify that you are using the right type of cable and adapter. For information about pin-out connections and installation instructions, refer to the Cisco 10000 ESR Hardware Installation Guide.
Make sure the cable is not defective or broken. Replace the cable with another high quality cable if possible, and check to see if the console port starts working.
Check that the terminal equipment is configured with the correct settings for the console port. The default console port settings are
- 9600 baud
- 8 data bits
- 1 stop bit
- No parity
- No flow control
Check the LEDs on the PRE faceplate to make sure it has powered up properly. If necessary, remove and reinsert both PRE modules to power them up again. Also, make sure the terminal equipment is working properly.

If the cable, connections, power, and terminal settings all check out and you still cannot connect to the console port on the module, replace the module in question. If the problem persists, contact the Cisco TAC for further assistance.

Fault	Steps to Take
STATUS LED is not lit	1. Check LEDs on other modules and cards. If none are lit, refer to Table 2-1 or Table 2-3 depending upon the PEM type in your chassis. 2. If LEDs on other modules and cards are lit, remove the card from its slot and check for bent or broken pins on the backplane. Return the card to its slot and screw it firmly into place. 3. Replace the card. 4. If the problem persists, contact the Cisco TAC.
FAIL LED is yellow, indicating that the PRE failed	1. Reinsert the PRE. 2. Insert a new PRE. 3. If the problem persists, contact the Cisco TAC.
The PRE initializes, but you cannot establish a console connection	1. Ensure that the terminal settings are properly set. 2. If you still cannot connect, check the console cable. Is it firmly connected? Is it the correct type of cable with proper connectors? 3. If the cable checks out and you cannot establish a console or Telnet session, reinsert the PRE module. If the problem persists, replace the PRE. 4. Enter show log to review console messages recorded in the system log.
Card cannot be fully inserted into its slot	Make sure that you are using slot 0A or 0B for the PRE module.
An alarm LED is lit	1. Enter the show facility-alarm status command and examine the output to determine which system component raised the alarm. 2. Troubleshoot using a procedure appropriate to the module or FRU responsible for the alarm. Refer to the following sections for information on interpreting alarms: OC-12 POS Line Card Alarms and Error Messages Channelized T3 (CT3) Line Card Alarms and Error Messages

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