svcadm(8)을 검색하려면 섹션에서 8 을 선택하고, 맨 페이지 이름에 svcadm을 입력하고 검색을 누른다.
textdump(4)
TEXTDUMP(4) BSD Kernel Interfaces Manual TEXTDUMP(4)
NAME
textdump — textdump kernel dumping facility
SYNOPSIS
options DDB
options KDB
options TEXTDUMP_PREFERRED
options TEXTDUMP_VERBOSE
DESCRIPTION
The textdump facility allows the capture of kernel debugging information
to disk in a human-readable rather than the machine-readable form nor‐
mally used with kernel memory dumps and minidumps. This representation,
while less complete in that it does not capture full kernel state, can
provide debugging information in a more compact, portable, and persistent
form than a traditional dump. By combining textdump with other ddb(4)
facilities, such as scripting and output capture, detailed bug informa‐
tion can be captured in a fully automated manner.
FORMAT
textdump data is stored in a dump partition in the same style as a regu‐
lar memory dump, and will be automatically extracted by savecore(8) if
present on boot.
textdump files are stored in the tar(5) format, and consist of one or
more text files, each storing a particular type of debugging output. The
following parts may be present:
ddb.txt Captured ddb(4) output, if the capture facility has been
used. May be disabled by clearing the
debug.ddb.textdump.do_ddb sysctl.
config.txt Kernel configuration, if options INCLUDE_CONFIG_FILE has
been compiled into the kernel. May be disabled by clearing
the debug.ddb.textdump.do_config sysctl.
msgbuf.txt Kernel message buffer, including recent console output if
the capture facility has been used. May be disabled by
clearing the debug.ddb.textdump.do_msgbuf sysctl.
panic.txt Kernel panic string, if the kernel panicked before the dump
was generated. May be disabled by clearing the
debug.ddb.textdump.do_panic sysctl.
version.txt Kernel version string. My be disabled by clearing the
debug.ddb.textdump.do_version sysctl.
Kernel textdumps may be extracted using tar(1).
CONFIGURATION
The textdump facility is enabled as part of the kernel debugger using
options KDB and options DDB. By default, kernel dumps generated on panic
or via explicit requests for a dump will be regular memory dumps; how‐
ever, by using the textdump set command in ddb(4), or by setting the
debug.ddb.textdump.pending sysctl to 1 using sysctl(8), it is possible to
request that the next dump be a textdump. One may also directly trigger
a textdump in ddb(4) by running the command textdump dump.
If at the ddb(4) command line, the commands textdump set, textdump
status, and textdump unset may be used to set, query, and clear the
textdump pending flag.
As with regular kernel dumps, a dump partition must be automatically or
manually configured using dumpon(8).
Additional kernel config(8) options:
TEXTDUMP_PREFERRED sets textdumps to be the default manner of doing
dumps. This means there will be no need to sysctl(8)
or use the textdump set ddb(8) commands.
TEXTDUMP_VERBOSE will have the textdump facility be more verbose about
each file it is emitting as well as other diagnostics
useful to debug the textdump facility itself.
EXAMPLES
In the following example, the script kdb.enter.panic will run when the
kernel debugger is entered as a result of a panic, enable output capture,
dump several useful pieces of debugging information, and then invoke
panic in order to force a kernel dump to be written out followed by a
reboot:
script kdb.enter.panic=textdump set; capture on; show allpcpu; bt;
ps; alltrace; show alllocks; call doadump; reset
In the following example, the script kdb.enter.witness will run when the
kernel debugger is entered as a result of a witness violation, printing
lock-related information for the user:
script kdb.enter.witness=show locks
These scripts may also be configured using the ddb(8) utility.
SEE ALSO
tar(1), ddb(4), tar(5), ddb(8), dumpon(8), savecore(8), sysctl(8)
HISTORY
The textdump facility first appeared in FreeBSD 7.1.
AUTHORS
The textdump facility was created by Robert N. M. Watson.
BSD December 24, 2008 BSD