Transition plan for changing the default init system

[Ansgar Burchardt]

Hi,

Tollef Fog Heen <tfheen at err.no> writes:
> So we are proposing the following scheme:
>
> a/ Upload a new "init" package. This is a new, essential package that
> will replace sysvinit as the package that ensures your system has an
> init system. We want to build this binary package from a package which
> is not tied to an actual init system, so we chose the
> init-system-helpers source package. Patch for init-system-helpers is
> available at [2].

Would it be possible to have "init" not be essential while we are
already changing things? There are valid use cases for init-less
systems, for example chroot environments.

invoke-rc.d and update-rc.d would probably still have to be in a
essential package, but not an entire init system.

> b/ Demote sysvinit to Priority: optional and install an extra copy of
> the sysvinit binary into /lib/sysvinit/ so you can recover if your
> system fails to boot with systemd. This can be achieved by booting with
> init=/lib/sysvinit/init on the kernel command line. Patch for sysvinit
> is available at [3].

On kfreebsd, init would then depend on an optional package as we don't
support arch-specific priorities. That is (IIRC) a policy violation, but
do any practical problems arise from this?

> c/ Upload a new version of the init package which does the actual switch
> and changes the order via Pre-Depends: systemd-sysv |
> sysvinit-core. Diff[4]

Why do a, and c, in two steps?

> d/ Adjust the priorities of systemd and systemd-sysv.

Ansgar