How to make systemd call the “status” command

systemdubuntu-16.04

We are replacing an Ubuntu 8.04 server with a Ubuntu 16.04. The server runs a single (non-OS) service that we need. (I'm the dev of that service, and not the sysadmin, which is on holiday this week) The service script looks about like this:

#!/bin/sh

# Load the VERBOSE setting and other rcS variables
. /lib/init/vars.sh

# Define LSB log_* functions.
# Depend on lsb-base (>= 3.0-6) to ensure that this file is present.
. /lib/lsb/init-functions


# ...

case "$1" in
  start)
    umask 002
    #...
    exit $?
    ;;

  stop)
    # ...
    exit $?
    ;;

  restart)
        stop || exit $?
        start
        exit $?
        ;;

  status)
       # ...
       exit $?
       ;;

  *)
    echo "Usage my_service (start|stop|restart|status)"
    exit 1;;
esac

After updating the path to Java … I got the service to work. But calling:

sudo service my_service status

returns some "standard" systemd output, instead of the code in the "status)" part of the script. Same result if I do this instead:

sudo /etc/init.d/my_service status

I'm not interested in what systemd thinks I want to know/see; I just want it to execute my code instead of it's own.

The output of "status" is parsed by some web-management console, and I don't want to have to change that application to take into account which version of Linux is installed on a specific server. "status" for the same service should output using the same format (IMO), independent of the specific OS version.

How do I tell systemd to "respect" my status command, instead of ignoring it?

Searching for "systemd status" did not get me anywhere, beyond the fact that I learned that systemd seems rather complicated.

Best Answer

systemd does not support custom status commands. You have a couple alternatives:

  1. You can keep a custom status command and call it directly instead through systemd.
  2. systemd provides machine-parsable status output via systemctl show your-service-name. As seen in man systemctl, you can also use systemctl set-property to set custom properties which can be reported back in the the status. You could teach your web-management console to parse this output instead.
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