Cisco Systems Troubleshooting Common Cisco Parity Errors in Network Routers

Chapter 3 Troubleshooting PRE-1 Modules

Troubleshooting Common System Problems

Fatal Alignment Errors

If the alignment error was a fatal error, it displays a message similar to the following:

%ALIGN-1-FATAL: Corrupted program counter error.

ERROR: Slot 0, NPE300/IOFE2/VXR, CACHE, External Data Cache Memory Test:

*** Data Expected= 0x99999999 ***

Fatal alignment errors are most likely a hardware fault on the processor card. The card itself could be faulty, or the memory on the card could be faulty. Try replacing the processor card and rebooting the router. If a replacement card is not available, try replacing the memory on the processor card, making sure that the new memory meets the specifications that are required by the card.

Low Memory Errors

The router can experience low memory errors for a number of reasons, including the following possible causes:

•The router is handling an excessively large volume of traffic. In particular, the router could be experiencing a large volume of traffic that requires special handling, such as ARP requests.

•Abnormal processes are using excessive amounts of memory.

•Large amounts of memory are still allocated to dead processes.

•Software errors could have resulted in memory leaks.

•Hardware problems with the memory on the processor card or line card.

•Hardware problems on the processor card or line card.

Low memory problems are usually indicated by one or more system messages (for example, SYS-2-MALLOCFAIL). For troubleshooting steps to resolve problems with low memory, see the Tech Note titled Troubleshooting Memory Problems, at the following URL:

http://www.cisco.com/warp/customer/63/mallocfail.shtml

Memory Parity Errors

	A memory parity error means that one or more bits at a memory location were unexpectedly changed
	after they were originally written. This error could indicate a potential problem with the Dynamic
	Random Access Memory (DRAM) that is onboard the PRE-1 module.
	Parity errors are not expected during normal operations and might force the router to reload. If the router
	did reload because of a parity error, the show version command displays a message such as “System
	restarted by processor memory parity error” or “System restarted by shared memory parity error.” For
	example:
	Router# show version
	Cisco Internetwork Operating System Software
	IOS (tm) 10000 Software (UBR10K-P6-M), Experimental Version 12.2(20031215:22350]
	Copyright (c) 1986-2003 by cisco Systems, Inc.
	Compiled Mon 15-Dec-03 17:28 by mnagai
	Image text-base: 0x60008968, data-base: 0x61B80000
	ROM: System Bootstrap, Version 12.0(9r)SL2, RELEASE SOFTWARE (fc1)
	BOOTLDR: 10000 Software (C10K-EBOOT-M), Version 12.0(17)ST, EARLY DEPLOYMENT RE)
	ubr10k uptime is 6 days, 18 hours, 59 minutes
	Cisco uBR10012 Universal Broadband Router Troubleshooting Guide
3-16	OL-1237-01