When sending a TERM signal to the kolabd master process kill $(cat /run/kolabd/kolabd.pid) the pidfile gets removed but the main process and it's childs don't stop. The childs never receive a kill signal and the master process waits until the childs will stop (which they never will).

Only killall kolabd will help. This is also the cause why the start-stop-daemon script fails when using the --pidfile options.

Solution is to kill childs created by multiprocessing when terminating the master process.