Daemonizing an executable in ansible

shell daemon ansible
user3364247 picture user3364247 · Apr 22, 2015 · Viewed 18.7k times · Source

I am trying to create a task in ansible which executes a shell command to run an executable in daemon mode using &. Something like following 

-name: Start daemon
  shell: myexeprogram arg1 arg2 &

What am seeing is if I keep & the task returns immediately and the process is not started . If I remove & ansible task waits for quite some time without returning.

Appreciate suggestion on proper way to start program in daemon mode through ansible. Pls note that I dont want to run this as a service but an adhoc background process based on certain conditions.

Answer

Karel Jakubec picture Karel Jakubec · Apr 23, 2015

Running program with '&' does not make program a daemon, it just runs in background. To make a "true daemon" your program should do steps described here.

If your program is written in C, you can call daemon() function, which will do it for you. Then you can start your program even without '&' at the end and it will be running as a daemon.

The other option is to call your program using daemon, which should do the job as well.

- name: Start daemon
  shell: daemon -- myexeprogram arg1 arg2

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