For monitoring I would try connecting to it; check that it's work spool is not growing larger than X or something else that works for the specific application.

For keeping a daemon alive I usually use the following for that kind of thing. If the process really wants to exit it does so with exit code 10; otherwise it'll get started again. 


#!/bin/sh

#  Keep a daemon running and running and running ...
#
#  Normally starts a process in the background
#  unless "bg" is given as the second argument.

trap '' 1 15 # ignore SIG HUP & TERM

PATH=/usr/xpg4/bin:$PATH # Solaris compatibility

if test `id -u` = 0
then 
  su - foo -c "$0 $1" &
  exit
fi

if test "$1" != "-bg"
then
  echo "$0 $$: Starting $* in background"
  $0 -bg "$@" &
  exit
fi

shift                   # remove the -bg
PROGRAM=$1; shift       # get and remove program name

while true
do
        echo "$0 $$: Starting $PROGRAM $@"
        $PROGRAM "$@" < /dev/null
        status=$?
        if test $status -eq 10 ; then
             msg="$PROGRAM $@ exited with status 10 - not restarted"
             logger -p 'local0.warning' "$msg"
             echo "$msg"
             exit 0
        fi
        msg="$PROGRAM $@ exited with status $status - will restart (pa
+rent=$$)"
        logger -p 'local0.warning' "$msg"
        echo "$msg"
        sleep 2
done

[download]
(replace foo with something else if you want to make sure you always start the program as a specific user).

 - ask 

-- 
ask bjoern hansen, http://ask.netcetera.dk/   !try; do();

In reply to Re: Best way to ensure process is live by ask
in thread Best way to ensure process is live by Anonymous Monk

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