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savecore(8) [ultrix man page]

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

Name
       savecore - save a core dump of the operating system

Syntax
       /etc/savecore [ options ] dirname [ system ] [ corename ]

Description
       The  command  is  meant	to  be called near the end of the file.  The command saves the core dump of the system (assuming one was made) and
       writes a reboot message in the shutdown log.

       The command checks the core dump to be certain it corresponds with the current running ULTRIX.  If it does, it saves the core image in  the
       file  dirname/vmcore.n and saves the namelist in the file dirname/vmunix.n.  The trailing .n in the pathnames is replaced by a number which
       increments each time is run in that directory.

       After saving the core and namelist images, will save the error logger buffer into a predetermined file.	The error logger  buffer  contains
       information about why the crash occurred.  After completes, the daemon will extract the error logger file and translate its contents into a
       form familiar to the program.

       Before writes out a core image, it reads a number from the file dirname/minfree.  If there are fewer free blocks  on  the  filesystem  that
       contains  dirname  than the number obtained from the file, a core dump is not done.  If the file does not exist, savecore always writes out
       the core file (assuming that a core dump was taken).

       The command also writes a reboot message in the shut down log.  If the system crashed as a result of a panic, also records the panic string
       in the shut down log.

       For  partial  crash  dumps,  creates  a	sparse	core image file in dirname/vmcore.n.  If this sparse core image file is copied or moved to
       another location, the file expands to its true size which can take too much file system space.  Hence, to copy or move  sparse  core  image
       files, you must use the command. The command has a conversion option to create sparse output files.

Options
       -c   Clears  the core dump.  This option is useful when the core dump is corrupted in a way that will not allow to save it safely.  Use the
	    option with caution, because once it clears the core dump, the core dump cannot be retrieved.

       -d dumpdev dumplo
	    Specifies the dump device and the dump offset when running on a system image other than the currently running system image.  The  pro-
	    gram  assumes  that  the running system image is and it reads the dump device and dump device offset are different in the system image
	    that crashed, the option provides the correct dump device and dump device offset.

       -e   Saves only the error logger buffer into a file.  If used, core or namelist images are not saved.

       -f corename
	    Takes the i corefile name as the file from which to extract the the crash dump data instead of the default dump device.   This  option
	    is used only for diskless workstations.

       If  the	core  dump was from a system other than /vmunix, the name of that system must be supplied as system.  The program assumes that the
       running image is

       After successful completion, the core dump is cleared.  Also, a message is written in the file which tells whether the  dump  succeeded	or
       failed.

Files
       Shut down log

       Current running ULTRIX system

See Also
       dd(1), uerf(8)

																       savecore(8)

Check Out this Related Man Page

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 5.11 25 Sep 2004 savecore(1M)
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