Bug#746577: closed by Michael Biebl <biebl at debian.org> (Re: Bug#746577: systemd-sysv: for upgrade safety, systemd-sysv and sysvinit-core must be coinstallable)

[Zack Weinberg]

On Fri, May 9, 2014 at 4:48 AM, Tollef Fog Heen <tfheen at err.no> wrote:
> ]] Zack Weinberg
>> Ah, I understand now.  Yes, this + systemd-sysv and upstart *also* stop
>> shipping /sbin/init (it becomes a symlink under control of the
>> administrator) + documentation would be a satisfactory conclusion as far
>> as I'm concerned.  If we were to also move 'reboot' and friends to a
>> shared utilities package, that might make the systemd-sysv package
>> unnecessary.
>
> I don't see any reason for the symlink being removed from systemd-sysv.
> After all, if you don't want that symlink, just use systemd, not -sysv.
...
> I'm quite ok with what we're doing now: if you're installing something
> that depends on systemd-sysv | systemd-shim, you get the new default
> (systemd).  If you don't like the new default, you get to take positive
> action to select what you would like to use instead.

Right, I think this is the heart of the remaining disagreement.

I don't think this is good enough, because in the common case, a
system upgraded from wheezy to jessie will have at least one package
that depends on libpam-systemd and therefore
systemd-sysv|systemd-shim.  It will be left with systemd-sysv
installed, systemd-shim not installed, and sysvinit-core removed.
Therefore, if the system fails to boot under systemd, the admin will
have to install packages to recover.

I want it to be that, in the common case, a system upgraded from
wheezy to jessie is left with ALL THREE of systemd-sysv, systemd-shim,
and sysvinit-core installed.  This is currently not possible because
of the file conflicts between systemd-sysv and sysvinit-core.  Most of
those could go away if we had a shared implementation of reboot and
friends, but there would still be the fundamental conflict over the
/sbin/init symlink.

I also think it would be better if /sbin/init continued to point to
/sbin/sysvinit until manually changed; but this is secondary.

zw