[systemd-devel] Question regarding ConditionPathExists= and systemctl status

[Lennart Poettering]

On Mon, 06.08.12 10:16, Holger Freyther (holger at freyther.de) wrote:

> Hi,
> 
> I have launched "systemd --user", created a bts.service file, added
> 'ConditionPathExists=' in the Unit section of my service. Then I
> launched my service with 'systemctl --user start ...' and  as the
> path does not exist, the condition_test fails and the service is not
> started.
> 
> Next I tried to figure out if I my users would be able to understand
> why the service was not started. This appears to be not possible.
> 
> The first part is that the Unit only holds condition_result and does
> not store which test failed. E.g. if a Unit has multiple tests it
> is not possible to know which test has failed. The debug output will
> simply state that one condition has failed. The second issue is that
> after the Unit has been garbage collected(???) the condition_result
> is gone and will not be restored. My users would have to query the
> status fast enough to maybe see the condition failure in the status.
> 
> Do you consider these issues worth fixing? Is this due running 
> systemd as a user?

So yupp, we currently do not store which conditions failed. It probably
makes sense to store that and expose it on the bus. (added this to the
TODO list now).

Whether we should GC the units or not is a problematic issue. We used to
keep more services around, but nowadays we GC services much more
aggressively. It's always a bit of a balance between "what is
interesting" and "let's save some memory", and the question where we
choose good defaults.

In a way "RemainAfterExit=yes" could be used to keep a service around even
on success, but that's a bit of a hack.

So, dunno, I am open to suggestions here...

Lennart

-- 
Lennart Poettering - Red Hat, Inc.