Bug#765803: Status of prompting / notification on upgrade for init system switch?

[Ian Jackson <ijackson@chiark.greenend.org.uk>]

Bdale Garbee writes ("Bug#765803: Status of prompting / notification on upgrade for init system switch?"):
> Russ Allbery <rra@debian.org> writes:
> > I think "default" is about what we install with fresh installs.
> > That's consistent with the other examples you list, where we've picked
> > a default.
> 
> I agree.

I think it would be helpful to write this up as a resolution.  How
about:

 -8<-

 1. In February the TC decided that the default init system for Linux
    in Debian jessie would be systemd.  We have been asked what this
    should mean for systems being upgraded from earlier Debian
    releases:

    Should existing installs be automatically switched to systemd ?
    Should users be prompted ?

 2. Normally when Debian changes the default provider of some service,
    this means that new installs get the new provider.  We do not
    transition existing installs to the new provider during upgrades,
    unless the old provider is being removed.

 3. The TC did not intend that our decision should extend to switching
    existing Debian GNU/Linux installations from sysvinit to systemd.
    Nor do we think that those users should be prompted to switch init
    system.

 4. So, if an existing installation has its init system switched, as a
    result of upgrading or of installing packages, that is a bug
    (unless it is not possible to retain the existing init system).

 -8<-

The caveat in (4) avoids prejudging the results of the coupling
question which is the subject of the GR process at the moment.

Ian.