HP-UX HB v13.00 Ch-08 - Crash Dumps

HP-UX Handbook – Rev 13.00 Page 17 (of 38)
Chapter 08 Crash Dumps
October 29, 2013
Saving the dump to the filesystem
After the system has finished to write the whole or only parts of the dump to the dump devices,
the system reboots and automatically starts up again. When booting up, the system starts a rc
script to copy the dump into the file system.
As of UX 11.00 the rc script itself is /sbin/init.d/savecrash. The configuration file is stored
at /etc/rc.config.d/savecrash. The default location is /var/adm/crash with sub directories
named crash.n for every saved crash. The crash.n directory contains an ASCII file named
INDEX that contains some metadata of the dump, a copy of the current kernel vmunix and files for
every saved contiguous chunk of memory named image.m.n. If the kernel contains loadable
modules, those are copied to the dump directory too.
You can configure crash directory, compression mode, etc. in the appropriate configuration file
/etc/rc.config.d/savecrash:
Here are the most important options:
SAVECRASH 1 = save a crashdump (default)
0 = do not save a crashdump
SAVECRASH_DIR directory for the crashfiles. Default is /var/adm/crash
COMPRESS 0 = never compress
1 = always compress
2 = compress in case of insufficient space in crasdirectory
(default)
Further options (MINFREE, SWAP_LEVEL, CHUNK_SIZE, SAVE_PART, FOREGRD, LOG_ONLY) are
explained in the comments of the config file.
Saving the dump manually
If the dump was not saved completely due to lack of space in the crash directory you have the
possibility to save the dump again. The -r option (resave) need to be included when this is not
the first time that savecrash runs.
# savecrash -v [-r] <crash directory>
NOTE: If after the crash, the system has been manually rebooted with a new kernel from the one
that was used at the time of the crash then you will need modify the options of savecrash with ‘-d
<path-of-kernel-file>’. In the same token, if the dump device has been changed then you would
need to add the options ‘-D <dumpdevice> -O <offset-in-Kbytes-on-the-dumpdevice>’.