Reload due to a watchdog timeout

[TCC_2]

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:

  "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:

  %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 these two ways:

• The show version command output shows:

  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:

  System returned to ROM by watchdog timer expired 
  *** Watch Dog Timeout *** 
  PC = 0x800001b4, SP = 0x61e19590

Resolution

Once you have identified a watchdog timeout message, refer to the Field Notices for your platform and all the components installed in that system for known critical hardware issues.

If a new module has been recently installed, first try to remove it to determine whether it is causing the watchdog timeout. If the watchdog timeout messages persists, try to re-seat all removable components. If the watchdog timeout continues, at this point there are no Field Notices for your hardware. If no new module has been recently installed, replace the main processor board.

On high-end platforms, the processor board is a separate card, such as the NPE-400 or RSP8. On low-end platforms (such as the Cisco 1700, 2500, 4000, 2600, or 3600 series), the motherboard cannot be shipped separately. In this case, you have to replace the chassis itself.

For more information on Watchdog Timeout crashes, refer to Troubleshooting Watchdog Timeouts.