savecore - save a crash dump of the operating system
/usr/bin/savecore [-L | -r] [-vd] [-f dumpfile] [directory]
The
savecore utility saves a crash dump of the kernel (assuming that one
was made) and writes a reboot message in the shutdown log. By default, it is
invoked by the
dumpadm service each time the system boots.
Depending on the
dumpadm(1M) configuration
savecore saves either
the compressed or uncompressed crash dump. The compressed crash dump is saved
in the file
directory/vmdump.n.
savecore saves the
uncompressed 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.
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 performed 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.
Open the dump device or file as read-only, and don't
update the dump header or do anything else that might modify the crash dump.
This option can be used to recover a crash dump from a read-only device. This
flag cannot be used in conjunction with -L.
-v
Verbose. Enables verbose error messages from
savecore.
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).
directory/vmdump.n
directory/vmcore.n
directory/unix.n
directory/bounds
directory/minfree
/var/crash/`uname -n`
default crash dump directory
adb(1),
mdb(1),
svcs(1),
dd(1M),
dumpadm(1M),
svcadm(1M),
syslog(3C),
attributes(5),
smf(5)
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 service'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.