Service with respawn, possible?

[ToLive]

Hi, everybody!

I,m trying to reach with goals new service :
1) On start - run two instances of "socat" with parameters; chmod 777 them;
2) On stop - kill only those two instances of "socat";
3) On restart - stop and start service;
4) On status - check if "socat" instances are running and if not - start them.

Here is my "service":

#!/bin/bash
    # chkconfig: - 98 02
    # description: socat service
    # processname: socat

    KIND="Socat"
    FsIn='/usr/bin/socat PTY,link=/dev/ttyS0,raw,echo=0 tcp4:192.168.0.188:7000'
    ScIn='/usr/bin/socat PTY,link=/dev/ttyS1,raw,echo=0 tcp4:192.168.0.188:7001'
    Port1=/dev/ttyS0
    Port2=/dev/ttyS1
    start() {
            echo -n $"Starting $KIND services: "
            $FsIn &
            $ScIn &
            chmod 777 $Port1
            chmod 777 $Port2
            echo
    }

    stop() {
            echo -n $"Shutting down $KIND services: "
            killproc $FsIn
            killproc $ScIn
            echo
    }

    restart() {
                echo -n $"Restarting $KIND services: "
                killproc $FsIn
                killproc $ScIn
                $FsIn &
                $ScIn &
                chmod 777 $Port1
                chmod 777 $Port2
                echo
    }

    status() {
     TEST='ps ax | grep -c $FsIn';
     if [ "$TEST" = "2" ];
     then
        echo "Alive :)"
     else
        echo "Dead :("
     fi
    }

    case "$1" in
      start)
              start
            ;;
      stop)
              stop
            ;;
      restart)
              restart
            ;;

      status)
              status
            ;;
      *)
            echo $"Usage: $0 {start|stop|restart|status}"
            exit 1
    esac
    exit $?

So, "status" section isn't working I have tried a lot of modifications, this is just one of them.
Can service watch for "socat" (maybe some "while" loop) instances and respawn them if they dies?
Thanks in advance!

[malcolmlewis]

Originally Posted by ToLive

Hi, everybody!

I,m trying to reach with goals new service :
1) On start - run two instances of "socat" with parameters; chmod 777
them;
2) On stop - kill only those two instances of "socat";
3) On restart - stop and start service;
4) On status - check if "socat" instances are running and if not -
start them.

Here is my "service":

Code:
--------------------

#!/bin/bash
# chkconfig: - 98 02
# description: socat service
# processname: socat

KIND="Socat"
FsIn='/usr/bin/socat PTY,link=/dev/ttyS0,raw,echo=0
tcp4:192.168.0.188:7000' ScIn='/usr/bin/socat
PTY,link=/dev/ttyS1,raw,echo=0 tcp4:192.168.0.188:7001' Port1=/dev/ttyS0
Port2=/dev/ttyS1
start() {
echo -n $"Starting $KIND services: "
$FsIn &
$ScIn &
chmod 777 $Port1
chmod 777 $Port2
echo
}

stop() {
echo -n $"Shutting down $KIND services: "
killproc $FsIn
killproc $ScIn
echo
}

restart() {
echo -n $"Restarting $KIND services: "
killproc $FsIn
killproc $ScIn
$FsIn &
$ScIn &
chmod 777 $Port1
chmod 777 $Port2
echo
}

status() {
TEST='ps ax | grep -c $FsIn';
if [ "$TEST" = "2" ];
then
echo "Alive "
else
echo "Dead "
fi
}

case "$1" in
start)
start
;;
stop)
stop
;;
restart)
restart
;;

status)
status
;;
*)
echo $"Usage: $0 {start|stop|restart|status}"
exit 1
esac
exit $?


--------------------

So, "status" section isn't working I have tried a lot of
modifications, this is just one of them.
Can service watch for "socat" (maybe some "while" loop) instances and
respawn them if they dies?
Thanks in advance!

Hi
If you look at /etc/init.d/skeleton for reference, look at touching a
pid file in /var/run and getting status from that.

--
Cheers Malcolm °¿° (Linux Counter #276890)
SUSE Linux Enterprise Desktop 11 (x86_64) Kernel 2.6.27.29-0.1-default
up 16:33, 2 users, load average: 0.07, 0.12, 0.28
GPU GeForce 8600 GTS Silent - CUDA Driver Version: 190.18

[ToLive]

Thanks for answer. But still no joy. Here is a part of my script:

start)
            echo -n $"Starting socat services: "
            Temp1=/var/run/socat1.pid
            FsIn='/usr/bin/socat PTY,link=/dev/ttyS0,raw,echo=0 tcp4:192.168.1.105:7000'
            Chk1=$(ps -fe | grep "$FsIn" | head -n1|cut -d" " -f 7)
            $FsIn &
            echo $Chk1 > $Temp1
            
          
 # Remember status and be verbose 
 rc_status -v
 ;;

I want to save the PID to /var/run/socat1.pid. If I exec it in console line by line, it works well. But when I'll try to exec the script, then nothing wrote to socat1.pid file.

P.S. Sorry for English, I'm in a hurry

[ken_yap]

Look at using /etc/inittab. Web search for inittab.

[ToLive]

I have tried inittab, but in some cases it can't respawn my process. For example, if I unplug network cable from comp and plug in it in 10 seconds. Only "init q" can help me in that case

[ken_yap]

So you write a wrapper that init calls to detect anomalous conditions and exit so that init can restart it. Maybe even create a watchdog process to monitor the work process. Thing is you end up writing your own respawn loop anyway if you write your own SysV init script instead of using inittab.

[ToLive]

Thanks for answer. I wrote a new script with infinity loop of "init q" and "sleep 30". In this way all working well by the first look