Bug#787758: 'Failed at step NAMESPACE spawning' when using ReadOnlyDirectories in multi-instance service file

[nusenu]

>> systemd version is on both (fresh and upgraded) systems 215-17, what
>> else should I check?
> 
> Eg. diff the list if installed packages you get via dpkg
> --get-selections and look for suspicouos diffs.

The upgraded system has sysvinit installed, the fresh one doesn't.
Both have systemd-sysv.

kernel matches;
3.16.0-4-amd64: 3.16.7-ckt9-3~deb8u1


> Local modifications, like custom fstab entries which override cgroupfs
> settings, stuff like that.

fstab looks common (no special changes)


> Can you provide steps how to reproduce the problem

Ok, I'll try to install a VM with an old debian -> upgrade -> test