[systemd-devel] [PATCH] networkd: disable tmpfiles and sysusers bits associated with networkd

[Tom Gundersen]

On Tue, Dec 2, 2014 at 10:24 AM, Łukasz Stelmach <l.stelmach at samsung.com> wrote:
> It was <2014-12-02 wto 00:35>, when Lennart Poettering wrote:
>> On Mon, 24.11.14 09:30, Łukasz Stelmach (l.stelmach at samsung.com) wrote:
>>
>>> It was <2014-11-21 pią 21:36>, when Lennart Poettering wrote:
>>> > On Fri, 21.11.14 17:07, Łukasz Stelmach (l.stelmach at samsung.com) wrote:
>>> >
>>> >> On a system configured without networkd and sysusers there still needs
>>> >> to be the unnecessary systemd-network user, otherwise systemd-tmpfiles
>>> >> fails to start.
>>> >>
>>> >> Move information associated with networkd in tmpfiles.d and sysusers.d
>>> >> to separate files. Do not install it if netwrorkd is not enabled.
>>> >
>>> > In principle looks OK, but I'd prefer if we would write this out with
>>> > m4 (see etc.conf.m4) and keep it in the current files, rather than
>>> > split this up in numerous files.
>>> >
>>> > Especially in the case of /run/systemd/netif this actually matters: if
>>> > we split that out into its own tmpfiles snippet, then packagers would
>>> > most likely put that in its own RPM/DEB if they split out those
>>> > daemons. But this is not advisable in this case, as sd-network (which
>>> > will eventually be a public API of libsystems) needs the directory to
>>> > be around to install an inotify watch. If the directory doesn't exist,
>>> > and the API is used it will fail entirely, which is suboptimal, given
>>> > that networkd might be installed later on, and things should then just
>>> > start to work.
>>>
>>> Will it be necessary for this directory to be owned by systemd-network
>>> even without networkd?
>>
>> Yes. If networkd is compile-time enable the dir should exist and be
>> properly owned, even if it networkd is split off into a separate
>> binary package and currently not installed.
>
> And what if the networkd is disabled? Does the directory must exist? Now
> if networkd is disabled /run/systemd/netif* are not in
> tmpfiles.d/systemd.conf. Is this correct?

No, if you disable networkd at compile-time the directory is not
needed (and using the sd-network library will rightly fail). The
reason we need to be able to use the sd-network library in case
networkd is enabled, but not installed is that you should be able to
start listening, _then_ install networkd, and then be notified of
events as if networkd was always installed.

However, that only really makes sense if you do enable networkd at
comiple-time, but ship it as a separate package. If you disable
networkd at compile-time, and then want to introduce it in the distro
(as separate package or as part of systemd), I don't think it is
unreasonable to expect to have to restart daemons that can optionally
integrate with networkd before they start picking up network events.

My two cents.

-t