[systemd-devel] Read-only /etc, machine-id with an overlay - journald failing

[Andreas Kempe]

On Thu, Feb 27, 2020 at 11:53:45PM +0100, Jérémy ROSEN wrote:
> Le jeu. 27 févr. 2020 à 16:30, Andreas Kempe <andreas.kempe at actia.se> a
> écrit :
> > I was contemplating whether it could be acceptable having the same
> > static machine-id file pre-generated for all systems. I'm not 100% sure
> > what it's used for, TBH; would it be a really bad idea?
> >
> 
> As long as two machines with the same machine-id are never in contact you
> should be fine...
> 
> Theoretically the machine-id should never cross the network, but you never
> know what individual apps might do
> 
> The only place where that could be problematic is the journal : if you mix
> the logs of multiple machines with the
> same machine-id, you won't be able to tell them appart and that might have
> other side-effects I wouldn't know about...
> 

AFAIK, we don't use the ID for anything in our own software and mixing
logs up shouldn't really be an issue, I think. I'll keep it in mind as
a potential workaround if nothing else.

Thank you for the help!
Cordially,
Andreas Kempe