Comment 20 for bug 1438612

(In reply to Simon McVittie from comment #6)
> How's this? I made the stop command be "echo" instead of "true" so that it
> leaves a hint in systemctl status if someone tries to stop it by hand.

Ah, good one.

> Unfortunately, "systemctl restart dbus" (which was never supported either)
> will now start a second dbus-daemon in parallel with the first, and in my
> testing, the second one will get all new connections. Any ideas for how to
> avoid that? Perhaps it would be better to make the stop command exit
> nonzero? ... but then we'd log scary messages during a normal shutdown,
> which is no better really.

Right, I don't like making it fail on stop. I don't see anything explicit which would declare "cannot restart"; I haven't tested this (travelling/no real computer), but would something like

    ConditionPathExists=!/run/dbus/system_bus_socket

prevent further starts/restarts? I'm not sure if conditions are evaluated on start only, or on restart too -- my gut feeling is the former, i. e. that won't work.

Thanks!

BTW, this is being discussed on the upstream ML too:

http://lists.freedesktop.org/archives/systemd-devel/2015-April/030070.html

(I haven't caught up with that yet)