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crash(1) [bsd man page]

CRASH(L)																  CRASH(L)

crash - analyze kernel dump or active system image SYNOPSIS
crash [ aps ] [ -bdvtiz ] [ -s sfile ] [ -c cfile ] [ -u addr ] DESCRIPTION
Synopsis of options - -b Brief mode; skip general display of processes -d Crash dump contains swap image. (default?) -v Verbose; dump much information about each proc [future] -t TTY structs to be dumpped -i Incore inode table to be printed -c FILE Provide non-standard file name for system image input -s FILE Provide non-standard symboltable input -u ADDR Trace a process other than currently selected one -z Interrupt Trace displayed aps Print PS & PC at time of interupt (doesn't do anything) crash examines a dump of unix which it looks for in the file sysdump. It prints out the contents of the general registers, the kernel stack and a traceback through the kernel stack. If an aps is specified, the ps and pc at time of interrupt are also printed out. The dump of the stack commences from a "reasonable" address and all addresses are relocated to virtual addresses by using the value of kdsa6 found in the dump. The following options may be specified. -b Brief mode; skip general display of processes. Only the currently selected process will be traced. -c cfile If the -c argument is found, the following argument is taken to be the name of a file containing the system image. The default is "/usr/sys/core". -s sfile If the -s argument is found the following argument is taken to be the name of a file, containing a symbol table which should be used in interpreting text addresses. The default is "/unix". -u addr Force a process to be displayed as if it were active when the crash occurred. addr is the octal address of the proc table entry. FILES
/unix system namelist /dev/swap swap device /usr/sys/core core file SEE ALSO
crash(8), adb(1), ps(1), rstat(1) DIAGNOSTICS
Missing arg Unable to Open file Format Error in symbolfile BUGS
Care should be used in running crash on "/dev/mem". Things can change while crash is running; the picture it gives is only a close approx- imation to reality. AUTHOR
Mike Muuss, JHU EE John Stewart, Teledyne Geotech March 1983 CRASH(L)

Check Out this Related Man Page

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

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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