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savecore(8) [bsd man page]

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

NAME
savecore - save a core dump of the operating system SYNOPSIS
savecore dirname [ system ] DESCRIPTION
Savecore is meant to be called at the end of the /etc/rc file. Its function is to save the core dump of the system (if one was made) and to write a reboot message in the shutdown log. It saves the core image in the file dirname/core.n and its corresponding namelist in dirname/unix.n. The second argument is the namelist for the system which made the core image; the current system is always assumed to be /unix. The trailing ".n" in the pathnames is replaced by a number which grows every time savecore is run in that directory. Before savecore writes out a core image, it reads a number from the file dirname/minfree. If there are fewer free blocks on the file sys- tem which contains dirname than the number obtained from the minfree file, the core dump is not done. If the minfree file does not exist, savecore always writes out the core file (assuming that a core dump was taken). Savecore also writes a reboot message in the shut down log. If the system crashed as a result of a panic, savecore records the panic string in the shut down log too. If savecore detects that the system time is wrong because of a crash (the time in the core image is after the current time), it will reset the system time to its best estimate of the time, which is the time in the core image plus the elapsed time since the reboot. It announces the time that it set when this occurs. FILES
/usr/adm/shutdownlogshutdown log /unix current UNIX BUGS
The method used to determine whether a dump is present, and to prevent the same core image from being saved multiple times, is not elegant. This information should be passed to init by the system; however, this is difficult because the system may have to be rebooted a second time if the root filesystem is patched. 3rd Berkeley Distribution SAVECORE(8)

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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)

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