Manualshelf

System information

ManualsBrandsDestination Audio ManualsComputer equipmentCS500C
481482483484485486487488489490
APPENDIX
Creating Core Dumps A-499
A
Creating Core Dumps
When a router crashes, it is sometimes useful to obtain a full copy of the memory image (called a
core dump) to identify the cause of the crash. Core dumps are generally useful only to your technical
support representative.
Note Use the commands discussed in this appendix only under the direction of a technical support
representative. Creating a core dump while the 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 Protocol (RCP) server and
subsequently interpreted by technical personnel who have access to source code and detailed
memory maps.
This appendix describes the exception, write core, and show commands.
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 router crashes, use the exception dump ip-address router
configuration command (where ip-address is the address of your TFTP server).
Including this command in your configuration causes the router to attempt to make a core dump
when it crashes. The core dump is written to a file named hostname-core on your TFTP server, where
hostname is the name of the router. You can change the name of the core file by configuring the
exception core-file filename command. This procedure can fail for certain types of system crashes.
However, if it is successful, the core dump file will be the size of the memory available on the
processor (for example, 16 MB for a CSC/4).
If you use TFTP to dump the core file to a server, the router will only dump the first 16 MB of the
core file. If the router’s memory is larger than 16 MB, the whole core file will not be copied to the
server. Therefore, use RCP or FTP to dump the core file.