bug#63869: [shepherd] `guix system reconfigure` forgets `herd disable mysrv`

[Ludovic Courtès]

Hi,

Maxim Cournoyer <maxim.cournoyer@gmail.com> skribis:

> Ludovic Courtès <ludo@gnu.org> writes:

[...]

>> When a service is stopped at the time of reconfigure, it is immediately
>> replaced and then started.
>>
>> Replacing works by unregistering the old instance from the registry and
>> registering a new one.  As a side effect, you end up with an instance
>> that’s enabled (see ‘service-registry’ in (shepherd services)).
>>
>> I never thought it could be a problem.  WDYT?
>
> I think it probably goes against users' expectation (i.e., systemd) that
> a disabled service stays disabled unless manually re-enabled (I think
> that's the way it is for systemd, even when the system is upgraded?).

Does systemd have a notion of enabled/disabled?

> If we want Guix/Shepherd to differ from this common expectation (on the
> ground that declarative should prevail over state, maybe?), it'd be good
> to have at least this documented/explained somewhere.
>
> What do you think?

I’m fine either way.  We can also change it such that replacing a
disabled service does not re-enable it; that’s probably more logical.

Thoughts?

Ludo’.