sentinel(1)sentinel(1)
HP Sentinel Tool
NAMEsentinel - Run time monitoring and debugging tool
SYNOPSIS-help
[-v] [-V] [<evt>[:<qual>] <act>]+ { <pid> | <command> <args> }
DESCRIPTION
IMPORTANT: Sentinel is delivered as part of the HP WDB debugger product
to enable the -crashdebug feature in gdb. There is no HP provided sup‐
port for the use of Sentinel as a standalone tool and it may not neces‐
sarily be part of any future releases of the WDB. We do welcome feed‐
back, directly sent to sentinel-help@cup.hp.com, if you use any of the
features of the standalone tool described below. Issues regarding using
Sentinel through gdb's -crashdebug option should be reported using your
regular HP support channel.
Sentinel is a tool to monitor the execution of a process and to take
specified actions in case of monitored events.
Events are essentially everything returned by ttrace (1M) call, along
with some qualifiers. Popular events are:
-sys system call
-sig signals
-exit program exit
-errexit non-zero exit
-abort exit due to uncaught signal (crash)
-fork used mostly with the action 'follow'
Each of these can be further qualified. For example, with -sys, you can
specify the system calls to make up that event. Thus -sys:open,close
will only monitor open and close system calls and none other (exit is
always monitored for logistics). For -sig, we can specify caught or
uncaught. With -exit, we can specify an exit code range. In fact,
-errexit is a special case of -exit (-exit:1-). A range of 1- means
everything greater than and including 1.
For the specified event, an action is also required if the event
occurs. Common actions are:
print Print the event
stats Give statistics of the type of event
core Dump core
coreplus Dump core + system and process forensics
mail Email $SENTINEL_MAIL or root@localhost
mailplus Collect core + forensics and send mail
debug Attach $SENTINEL_DEBUGGER or gdb in $PATH
follow Used with -fork => trace children.
OPTIONS
Any arguments other than options specify a command to execute (along
with its arguments) or an all-numeric argument signifying the pid of a
process to attach to.
Other command line options are described below:
-v Verbose
-V Version information
-silent or -Q No output
-odir <dir> Place output directories under <dir> directory
-nodir All output to stdout and not to subdirectories
-stdout Same as -nodir
-stderr Output to -stderr
-help Help with examples
NOTES
Starting with WDB 5.6 (released Feb 2007), Sentinel can also be invoked
through gdb, by using the option -crashdebug on gdb. It comes bundled
with the wdb depot and gets installed under /opt/sentinel directory.
Settings are provided under /opt/sentinel/config/setup.sh script.
EXAMPLESsentinel -sys:1-5 print 1224
print syscalls 1 - 5 for process id 1224
sentinel -sys:open,close print ls
print open/close sys calls for ls
sentinel-abort debug gensig11
attach to $SENTINEL_DEBUGGER env var (or gdb in $PATH). Also see
/opt/sentinel/docs/examples/sig11 for other usages.
sentinel-fork follow -abort debug /bin/ksh
track crashes in a ksh session
sentinel-sig core gensig11
dump multiple core.pid.<n> files
sentinel-abort coreplus gensig11
core + other process/system info
OUTPUT FORMAT
By default Sentinel creates a sub-directory called sentinel.<pid> under
the current directory. Inside, all output is placed under a file called
s.<pid>.txt. All other files, like a core file or coreplus output is
also placed in that directory. In case, -fork follow option is speci‐
fied, all children's corresponding directories are placed under the
parents' directories.
Using -nodir, an alternate top level directory can be specified to
place sentinel.<pid> directories.
-stderr, -stdout, -nodir can be used to send output to screen.
-silent sends no output to the screen or to a directory.
ENVIRONMENT VARIABLES
Sentinel supports the following environment variables. These can also
be seen in the file config/setup.sh provided with the package.
SENTINEL_OPTIONS and SENTINEL_OVERRIDE_OPTIONS contain command line
options. The actual command line takes priority over SENTINEL_OPTIONS
if there is an overlap, but SENTINEL_OVERRIDE_OPTIONS takes priority
over the command line.
SENTINEL_DEBUGGER holds the path of the debugger to be invoked in case
the debug action is used. SENTINEL_DEBUGRC holds the path of a gdb com‐
mands file to be passed to gdb (through -x file option of gdb).
SENTINEL_MAIL holds the email address for a mail to be sent in case
mail or mailplus actions are used. The default is root@localhost.
SENTINEL_FORENSICS contains the path of an executable or shell script
to be invoked for information collection in case of coreplus and
mailplus options. By default Sentinel collects information using stan‐
dard commands. If presents, the file scripts/forensics.sh can be used
as a reference for the same.
sentinel(1)
