[systemd-devel] How to disable unit under /lib/systemd/system/*.wants?

[Kay Sievers]

On Tue, Sep 21, 2010 at 00:20, Lennart Poettering
<lennart at poettering.net> wrote:
> On Sat, 18.09.10 21:39, Andrey Borzenkov (arvidjaar at mail.ru) wrote:
>
>> Let's assume unit foo is installed as wanted by other unit under
>> $systemunitdir (/lib/systemd/system/bar.wants/foo). How can I now
>> disable it? systemctl (enable|disable) only manipulates links under
>> $pkgsysconfdir, so "systemctl disable foo" in this case does nothing.
>>
>> Such links are created during standard installation of systemd.
>
> Services enabled via /lib/systemd/system/xxxx.wants/ are not intended to
> be disabled by the user/admin.
>
> The idea is that we link only those services in /etc/systemd/system
> where the admin/user has a good reason to disable them. However all
> really basic services that are integral part of the OS are symlinked
> directly in /lib/systemd/system, thus offering less of a chance for
> breakage and making things less fragile.
>
> Speaking with an example: the admin/user might have a good reason to
> enable/disable an installed apache, but there's little point in
> disabling/enabling really basic services such as hwclock.service, which
> we hence pull in unconditionally,
>
> If some distros decide to disable these services nonetheless, then they
> can do that by doing "rm" after the "make install". But disabling those
> services should be left to the distros, not the admin/user.
>
> The line between those services which are enabled via /etc and those
> enabled via /lib is the same line which seperates stuff that is supposed
> to be under admin/user control from stuff under OS developer control.

You can also link the service to /dev/null in /etc, it will overwrite
all stuff in /lib, just like the udev rules work.

Kay