Core Issue
Cisco processors have timers that guard against certain types of system hangs. The CPU periodically resets a watchdog timer. The watchdog timer basically controls the time of each process. If the timer is not reset, a trap occurs. If a process is longer than it should be, the watchdog timer is used to escape from this process.
There are two main types of watchdog timeouts. The first type is usually caused by a software problem and is reported in one or both of these ways:
- The show version command output shows this:
"System returned to ROM by bus error at PC 0x602DADE0, address 0x480811" - or -
"System returned to ROM by error - a Software forced crash, PC 0x60435894"
- The console logs show this:
%SYS-2-WATCHDOG: Process aborted on watchdog timeout
The second type of watchdog timeout is usually due to a hardware problem and is reported in one or both of the these ways:
- The show version command output shows this:
Router uptime is 17 minutes
System returned to ROM by watchdog timer expired
System image file is "flash:c3640-is-mz.122-3.bin"
- The console logs show this:
System returned to ROM by watchdog timer expired
*** Watch Dog Timeout ***
PC = 0x800001b4, SP = 0x61e19590
Resolution
For information on this issue, refer to Field Notice: Watch Dog Timeouts on 2600/3700 Series Routers with AIM Module.
For more information on watchdog timeout crashes, refer to Troubleshooting Watchdog Timeouts.
When hardware replacement is indicated after troubleshooting:
- If you have a hardware support contract directly with Cisco for this part, use the Service Order Submit Tool to request a replacement part directly.
- For warranty service, contact the Cisco Technical Assistance Center (TAC) directly at 1-800-553-2447, or online using the TAC Service Request Tool.
- If your product is not covered by contract or warranty, contact your Cisco Partner or Reseller to request a replacement part for the hardware component that is causing the issue.
