Restarting Upstart instance processes

Question

I am running multiple instances of a worker as described in this answer: Starting multiple upstart instances automatically

Question: Can I restart all instan

Answer 1

In worker.conf you just need to change this line:

stop on shutdown

To:

stop on stopping my-workers

And change my-workers.conf to use pre-start instead of script:

pre-start script
  for i in `seq 1 $NUM_WORKERS`
  do
    start worker N=$i
  done
end script

Now my-workers will keep state: since the work happens in pre-start, the my-workers main process won't exist and so won't exit. stop on stopping my-workers causes the workers to stop whenever my-workers is stopped. Then of course when it starts up again it will start the workers again.

(FYI, stop on shutdown does nothing, as shutdown is not a system event. man upstart-events for all the defined events) so you should also change my-workers to stop on runlevel [06]