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expand_dump(8) [osf1 man page]

expand_dump(8)						      System Manager's Manual						    expand_dump(8)

NAME
expand_dump - Produces a non-compressed kernel crash dump file SYNOPSIS
/usr/sbin/expand_dump input-file output-file DESCRIPTION
By default, kernel crash dump files (vmzcore.#) are compressed during the crash dump. Compressed core files can be examined by the latest versions of debugging tools that have been recompiled to support compressed crash dump files. However, not all debugging tools may be upgraded on a given system, or you may want to examine a crash dump from a remote system using an older version of a tool. The expand_dump utility produces a file that can be read by tools that have not been upgraded to support compressed crash dump files. This non-compressed version can also be read by any upgraded tool. This utility can only be used with compressed crash dump files, and does not support any other form of compressed file. You cannot use other decompression tools such as compress, gzip, or zip on a compressed crash dump file. Note that the non-compressed file will require significantly more disk storage space as it is possible to achieve compression ratios of up to 60:1. Check the available disk space before running expand_dump and estimate the size of the non-compressed file as follows: Run tests by halting your system and forcing a crash as described in the Kernel Debugging manual. Use an upgraded debugger to determine the value of the variable dumpsize. Multiply this vale by the 8Kb page size to approximate the required disk space of the non-compressed crash-dump. Run expand_dump and pipe the output file to /dev/null, noting the size of the file that is printed when expand_dump completes its task. RETURN VALUES
Successful completion of the decompression. The user did not supply the correct number of command line arguments. The input file could not be read. The input file is not a compressed dump, or is corrupted. The output file could not be created or opened for writing and truncated. There was some problem writing to the output file (probably a full disk). The input file is not formated consistantly. It is probably corrupted. The input file could not be correctly decompressed. It is probably corrupted. EXAMPLES
expand_dump vmzcore.4 vmcore.4 SEE ALSO
Commands: dbx(1), kdbx(8), ladebug(1), savecore(8) Kernel Debugging System Administration expand_dump(8)

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savecore(1M)						  System Administration Commands					      savecore(1M)

NAME
savecore - save a crash dump of the operating system SYNOPSIS
/usr/bin/savecore [-Lvd] [-f dumpfile] [directory] DESCRIPTION
The savecore utility saves a crash dump of the kernel (assuming that one was made) and writes a reboot message in the shutdown log. It is invoked by the dumpadm service each time the system boots. savecore saves the crash dump data in the file directory/vmcore.n and the kernel's namelist in directory/unix.n. The trailing .n in the pathnames is replaced by a number which grows every time savecore is run in that directory. Before writing out a crash dump, savecore reads a number from the file directory/minfree. This is the minimum number of kilobytes that must remain free on the file system containing directory. If after saving the crash dump the file system containing directory would have less free space the number of kilobytes specified in minfree, the crash dump is not saved. if the minfree file does not exist, savecore assumes a minfree value of 1 megabyte. The savecore utility also logs a reboot message using facility LOG_AUTH (see syslog(3C)). If the system crashed as a result of a panic, savecore logs the panic string too. OPTIONS
The following options are supported: -d Disregard dump header valid flag. Force savecore to attempt to save a crash dump even if the header information stored on the dump device indicates the dump has already been saved. -f dumpfile Attempt to save a crash dump from the specified file instead of from the system's current dump device. This option may be useful if the information stored on the dump device has been copied to an on-disk file by means of the dd(1M) command. -L Save a crash dump of the live running Solaris system, without actually rebooting or altering the system in any way. This option forces savecore to save a live snapshot of the system to the dump device, and then immediately to retrieve the data and to write it out to a new set of crash dump files in the specified directory. Live system crash dumps can only be per- formed if you have configured your system to have a dedicated dump device using dumpadm(1M). savecore -L does not suspend the system, so the contents of memory continue to change while the dump is saved. This means that live crash dumps are not fully self-consistent. -v Verbose. Enables verbose error messages from savecore. OPERANDS
The following operands are supported: directory Save the crash dump files to the specified directory. If directory is not specified, savecore saves the crash dump files to the default savecore directory, configured by dumpadm(1M). FILES
directory/vmcore.n directory/unix.n directory/bounds directory/minfree /var/crash/'uname -n' default crash dump directory ATTRIBUTES
See attributes(5) for descriptions of the following attributes: +-----------------------------+-----------------------------+ | ATTRIBUTE TYPE | ATTRIBUTE VALUE | +-----------------------------+-----------------------------+ |Availability |SUNWcsu | +-----------------------------+-----------------------------+ SEE ALSO
adb(1), mdb(1), svcs(1), dd(1M), dumpadm(1M), svcadm(1M), syslog(3C), attributes(5), smf(5) NOTES
The system crash dump service is managed by the service management facility, smf(5), under the service identifier: svc:/system/dumpadm:default Administrative actions on this service, such as enabling, disabling, or requesting restart, can be performed using svcadm(1M). The ser- vice's status can be queried using the svcs(1) command. If the dump device is also being used as a swap device, you must run savecore very soon after booting, before the swap space containing the crash dump is overwritten by programs currently running. SunOS 5.10 25 Sep 2004 savecore(1M)
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