SAVECORE(8) Maintenance Procedures SAVECORE(8)
NAME
savecore - save a crash dump of the operating system
SYNOPSIS
/usr/bin/savecore [
-L |
-r] [
-vd] [
-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. By default, it
is invoked by the
dumpadm service each time the system boots.
Depending on the
dumpadm(8) 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.
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(8) 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(8).
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.
-r 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.
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(8).
FILES
directory/vmdump.n directory/vmcore.n directory/unix.n directory/bounds directory/minfree /var/crash/`uname -n` default crash dump directory
SEE ALSO
adb(1),
mdb(1),
svcs(1),
syslog(3C),
attributes(7),
smf(7),
dd(8),
dumpadm(8),
svcadm(8)NOTES
The system crash dump service is managed by the service management
facility,
smf(7), 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(8). 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.
February 22, 2019
SAVECORE(8)