Troubleshooting guide

D-1
ATM and Layer 3 Switch Router Troubleshooting Guide
OL-1969-01
APPENDIX D
Creating a Core Dump
If the switch router fails, it is sometimes useful to get a full copy of the memory image, called a core
dump, to identify the cause of the failure. Core dumps are generally only useful to your technical support
representative.
Caution Use the commands discussed in this appendix only under the direction of a technical support
representative. Creating a core dump while the switch router is functioning in a network can disrupt
network operation. The resulting binary file, which is very large, must be transferred to a Trivial File
Transfer Protocol (TFTP), File Transfer Protocol (FTP), or remote copy (rcp) server. It is
subsequently interpreted by technical personnel who have access to source code and detailed memory
maps.
Using exception Commands
Use the exception class of configuration commands only after consulting with a technical support
representative. These commands are useful for debugging purposes, but they can result in unexpected
behavior.
Creating a Core Dump
To obtain a core dump when a switch router fails, use the exception dump ip-address switch router
configuration command (where ip-address is the address of your TFTP server).
If you include this command in your configuration, the switch router attempts a core dump when it
crashes. The core dump is written to a file named hostname-core on your server, where hostname is the
name of the switch router. You can change the name of the core file by entering the exception
core-file filename command.
The default protocol for transferring the core dump is TFTP. However, TFTP transfers only 16 MB of
the core dump file. If the switch router memory is over 16 MB, only the first 16 MB is transferred. To
transfer the whole core dump, configure the switch router to use rcp or FTP for core dumps with the
exception protocol command.