Compressed Dump

Compressed Dump White Paper, Version 1.3
page 17
crash will not perform any compression.
When dirname is specified with the -t option, dirname is the name
of the existing directory where the INDEX file is created; the
default directory is /tmp. The INDEX file is the first file that is writ-
ten out to the dump tape. This file is written a second time once
all the dump files have been written. The first copy of the file only
contains crash dump header information and its filename on tape
is tmpindex. It does not contain information for the module and
image files.
When writing to tape, the tape device must be online otherwise
the command will fail with an error. Additionally, when savecrash
reaches end-of-tape, it will prompt the user for the next tape. Any
tape errors encountered will result in a generic tape error.
-w opt Defines the interaction between savecrash and swapon. opt can
be one of the following values:
NOSWAP Do not run swapon from savecrash.
SWAPEACH (default) Call swapon each time savecrash fin-
ishes saving the image from each dump device. This option pro-
vides the most efficient use of paging space.
SWAPEND Only call swapon when savecrash finishes saving
the image file from all dump devices. If this option is used, no
additional paging space other than the primary paging space is
available until the complete crash dump image is saved. This
option provides a second chance to retrieve the crash image if
savecrash fails on first attempt.
For compatibility with earlier savecore syntax, the values of 0, 1
and 2 can be used in place of NOSWAP, SWAPEACH, and
SWAPEND, respectively. This usage is obsolescent.
RETURN VALUE
Upon exit, savecrash returns the following values:
0 A crash dump was found and saved, or savecrash has preserved dump
information from the primary swap device and is continuing to run in the
background to complete its tasks.
1 A crash dump could not be saved due to an error.
2 No crash dump was found to save.
3 A partial crash dump was saved, but there was insufficient space to pre-
serve the complete dump.
4 The savecrash process continued in the background, see the INDEX file
for actual results.
WARNINGS