[systemd-devel] Explain status "Loaded: not-found (Reason: No such file or directory)"

[Lennart Poettering]

On Do, 09.05.19 12:25, Ulrich Windl (Ulrich.Windl at rz.uni-regensburg.de) wrote:

> Hi!
>
> I'm developing a service and getting the status of my target gives:
> ● iotwatch.target
>    Loaded: not-found (Reason: No such file or directory)
>    Active: active since Thu 2019-05-09 12:00:56 CEST; 18min ago
>
> I guess it's not a file named "Reason" that's missing. Despite of my
> recommendation to create helpful error messages, can you explain what it means?
> Even after an strace I could not find out what is missing.

"Loaded" is a field that indicates whether the unit definition was
properly loaded from the unit file. Here, it's shown as "not-found",
which is the value indicating that no unit file by the name
"iotwatch.target" could be found. Then, in brackets you get some
additional information: here "Reason:" is the field that indicates the
reason why the unit file wasn't found, and this usually gives you a
UNIX error code, i.e. the text string associated with an "errno"
code. "No such file or directory" is the string for ENOENT, i.e. it's
the simplest of cases here: there really just was no file found by the
name you requested.

Typically, when you see "not-found" as "Loaded" value, you'll also see
"No such file or directory" as "Reason" value, but there are some
other cases, since units are not always synthesized from unit files on
disk, but from other concepts too.

Lennart

--
Lennart Poettering, Berlin