systemd ordering cycle

[Trent Lloyd]

Sometimes there is a systemd srevice ordering cycle that prevents it from cleanly starting everything.

In such cases it will arbitrarily delete some dependencies or start jobs, which can result in some random services having not started.

We should alert on these messages. Example:

Jul 30 05:35:32 localhost systemd[1]: network-pre.target: Found ordering cycle on networking.service/stop
Jul 30 05:35:32 localhost systemd[1]: network-pre.target: Job networking.service/stop deleted to break ordering cycle starting with network-pre.target/stop
Jul 30 06:02:55 localhost kernel: [   24.313121] systemd[1]: firewalld.service: Found ordering cycle on dbus.socket/start
Jul 30 06:02:55 localhost kernel: [   24.384791] systemd[1]: firewalld.service: Job dbus.socket/start deleted to break ordering cycle starting with firewalld.service/start