Cisco Systems DOC-7814982 Using the crashinfo File

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Catalyst 2950 Desktop Switch Software Configuration Guide

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Chapter 28 Troubleshooting Using th e cra shinf o File

Beginning in privileged EXEC mode, enter this command to enable all-system diagnostics:

Switch# debug all

Caution Because debugging output takes priority over other network traff ic, and because the debug all pri vileged

EXEC command generates more output than any other debug command, it can se ve rely diminish switch

performance or even render it unusable. In virtually all cases, it is best to use more specific debug

comm an ds.

The no debug all privileged EXEC comm and disab les all diagnosti c output . Using the no debug all

comm and is a convenient way to ensure th at you have not accide ntally l eft any debug commands

enabled.

By default, the network server sends the output from debug commands and system error messages to the

console . If you use this de fault, you can use a virtu al term inal conn ection to monitor debug output

instead of connec ting to the co nsole po rt.

Possible destinations include the console, virtual terminals, internal buffer, and UNIX hosts running a

syslog server. The syslog format is compatible with 4.3 Berkeley Standard Distribution (BSD) UNIX

and its derivatives.

Note Be aware that the debuggin g destin ation yo u use affects system overhead. Lo gging messages to the

console produces very high overhea d, wherea s logging me ssages to a vir tual termi nal produce s less

overhead. Lo gging m ess age s to a s yslog se rver pro duc es even less, an d lo gging t o an inte rn al buffer

produce s the least overhea d of any method.

Using the crashinfo File

The crashinfo file saves information that helps Cisco technical support representatives to debug

problems that caused the IOS image to fail (crash). The switch writes the crash information to the

console at the time of the failure, and the file is created the next time you boot the IOS image after the

failure (instead of while the system is failing).

The informati on in the f ile includes the IOS imag e name and ve rsion that fa iled, a dump of the processo r

registers, an d a stack trac e. You can provid e this in formatio n to the Cis co techni cal suppor t

represe nta tive by using th e show tech-support privileged EXEC command.

All crashinfo files are kept in this directory on the Flash file system:

flash:/crashinfo/crashinfo_n where n is a sequence number.