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SegV exceptions

Core Issue

Segmentation Violation (SegV) exceptions are always software problems. These issues may lead to a SegV exception:

  • Access to an invalid memory address
  • Write access to a read-only memory region
  • A jump to an invalid PC (often 0x0)


If you do not power-cycle or manually reload the router, the show version command displays one of these outputs: 

  • Router uptime is 2 days, 3 hours, 5 minutes 
    System restarted by error - a SegV exception, PC 0x80245F7C
    System image file is "flash:c2600-js-mz.120-9.bin"
  • Router uptime is 11 hours, 38 minutes 
    System returned to ROM by error - a SegV exception, PC 0x80249B0C
    System image file is "flash:c2600-is-mz.121-1.5.bin"

These lines may also be present in the console logs: 

*** System received a SegV exception ***

signal= 0xb, code= 0x1200, context= 0x80d15094

PC = 0x80678854, Vector = 0x1200, SP = 0x80fcf170


If you have not manually reloaded or power-cycled the router since the SegV exception, you can search for a known matching Cisco bug ID using the Output Interpreter tool.   

If you have the output of a show stacks command from your Cisco device, you can use Output Interpreter tool to display potential issues and fixes.

If the decoded output from the show stacks command matches a known software bug, you will receive the Cisco bug IDs of the most likely software bugs that could have caused the SegV exception. Click on the bug ID hyperlinks to view additional bug details from the Bug Toolkit, which can help you determine the correct Cisco bug ID match. Once you have identified a matching bug ID, refer to the fixed in field to determine the first Cisco IOS  Software version that contains the fix for the bug. 

If you are uncertain which Cisco bug ID matches or which Cisco IOS Software version contains the fix for the problem, refer to Cisco Downloads for the latest version in your release train. 

For more information, refer to SegV Exceptions.

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Last update:
‎06-22-2009 04:06 PM
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