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.Dd January 14, 2024 .Dt CRASH 8 .Os .Sh NAME .Nm crash .Nd examine and debug system images .Sh SYNOPSIS .Nm .Op Fl w .Op Fl M Ar core .Op Fl N Ar kernel .Sh DESCRIPTION The .Nm command is used to examine and debug system images.
p If run without any arguments, .Nm operates on the running system.
p The options are as follows: l -tag -width xpalidocious t Fl M Ar core Operate on the specified crash dump instead of the default
a /dev/mem . Crash dumps should be from the same version of the system and same machine architecture as the running version of .Nm crash , and must be uncompressed. t Fl N Ar kernel Extract the name list from the specified kernel instead of the default
a /dev/ksyms . t Fl w Enable writing. .El
p The command syntax used by .Nm is the same as the in-kernel debugger. See the .Xr ddb 4 manual page for more information.
p Operations and facilities that require a running system, such as breakpoints, are not supported by .Nm crash .
p .Nm does not provide pagination. However, by using the pipe symbol, output may be sent to commands available from the shell. For example: d -literal -offset abcd crash> ps | more crash> ps | grep ioflush .Ed .Sh EXAMPLES You can obtain a full list of all kernel stack traces with a shell pipeline like the following: d -literal -offset abcd # echo ps | crash | grep '^[0-9]' | cut -c 30-46 | \\ sed 's,^,bt/a ,' | crash .Ed .Sh SEE ALSO .Xr ps 1 , .Xr vmstat 1 , .Xr ddb 4 , .Xr pstat 8 , .Xr savecore 8 .Sh HISTORY The .Nm command appeared in .Nx 6.0 . .Sh BUGS The .Nm command for the sparc port is unstable.
Indexes created Sun Sep 21 20:09:37 GMT 2025