Managing Systems and Workgroups: A Guide for HP-UX System Administrators

Administering a System: Booting and Shutdown
Abnormal System Shutdowns
Chapter 5552
After your system is rebooted, one of the first things you need to do is to
be sure that the physical memory image that was dumped to the dump
devices is copied to the HP-UX file system area so that you can either
package it up and send it to an expert for analysis, or analyze it yourself
using a debugger.
NOTE As of HP-UX Release 11.0, it is possible to analyze a crash dump directly
from dump devices using a debugger that supports this feature. But if
you need to save it to removable media, or send it to someone, you first
need to copy the memory image to the HP-UX file system area. See also
the information on converting compressed dumps in “Converting the
Format of Compressed Dumps” on page 554.
Unless you specifically disable savecrash processing during reboot (see
“The savecrash Processing Option” on page 551), the savecrash utility
will copy the memory image for you during the reboot process. The
default HP-UX directory that it will put the memory image in is
/var/adm/crash. You can specify a different location by editing the file
/etc/rc.config.d/savecrash and setting the environment variable
called SAVECRASH_DIR to the name of the directory where you would like
the dumps to be located.
Using crashutil to Complete the Saving of a Dump
If you are using devices for both paging (swapping) and dumping, it is
very important not to disable savecrash processing at boot time. If you
do, there is a chance that the memory image in your dump area will be
overwritten by normal paging activity. If, however, you have separate
dump and paging devices (no single device is used for both purposes), you
can delay the copying of the memory image to the HP-UX file system
area in order to speed up the boot process, to get your system up and
running as soon as possible. You do this by editing the file
/etc/rc.config.d/savecrash and setting the environment variable
called SAVECRASH=0.
If you have delayed the copying of the physical memory image from the
dump devices to the HP-UX file system area in this way, run savecrash
manually to do the copy when your system is running and when you have
made enough room to hold the copy in your HP-UX file system area.