On Sun, 2013-12-08 at 18:22 +0100, Heinz Diehl wrote: > On 08.12.2013, Greg Woods wrote: > > > I am trying to find a way to get a service to restart when the system is > > resumed from suspend or hibernation. > > You can place a script in /usr/lib/systemd/system-sleep Thanks for the tip on that. I now remember that I had tried this before and it didn't work. I played with this for a couple of hours today, and discovered that the reason it didn't work is that you can't call "systemctl" from this script. In retrospect I should have realized this, because this script runs while systemd is busy changing states and it is executing things in a tree, and running "systemctl" is like suddenly lopping off a branch to that tree (or adding a new one), and this will have unpredictable results. This comes from me still thinking about things in the old way. To use systemd, you have to think in terms of how systemd works, not in terms of how the old init scripts work. It was bizarre; when I had a "systemctl restart racoon" command in my system-sleep script, what would happen is that suspend would hang, issuing a long single beep about every 25 seconds or so. After a couple of minutes, it would finally suspend. On resume, it would just keep single-beeping every 25 seconds forever; it would never come back from suspend. This was 100% reproducible; put the systemctl command in the script, it goes into "beep mode". Take it out, and suspend works normally again. What finally worked was to change the service definition for the racoon service to automatically restart it when the daemon died, then insert commands into the system-sleep script to explicitly kill the daemon on suspend or hibernate. On resume, systemd notices that the daemon is gone and restarts it (I don't try to restart it in the system-sleep script; I first tried that and wound up with two copies of the daemon running). So I end up with just a "killall racoon" command in the system-sleep script, and setting Restart=always in the service file. --Greg -- users mailing list users@xxxxxxxxxxxxxxxxxxxxxxx To unsubscribe or change subscription options: https://admin.fedoraproject.org/mailman/listinfo/users Fedora Code of Conduct: http://fedoraproject.org/code-of-conduct Guidelines: http://fedoraproject.org/wiki/Mailing_list_guidelines Have a question? Ask away: http://ask.fedoraproject.org
