Re: r/o root filesystem?
Greg Stark wrote:
> Andreas Metzler <ametzler@downhill.@.eu.org> writes:
> > Greg Stark <firstname.lastname@example.org> wrote:
> > [...]
> > > I don't think policy says anything about this,
> > [...]
> > FHS say that /etc/ is supposed to contain static data, but of course
> > this only applies to normal operation, i.e. it is perfectly ok to
> > write to /etc/ on bootup.
> Well it's ok if we say it's ok. I'm saying perhaps since there's so little
> that requires it we should decide it's worthwhile to give up those few places
> and make ro root filesystems a supported configuration.
> > interesting files: mtab, modules.conf,
> indeed. I seem to recall mtab can be a symlink to /proc/mounts but I'm not
> certain on the consequences of that.
I think mount (without options for listing what's mounted) may be
confused for some devices. I think I've tried it, and it's nothing you
can't live with (it doesn't really break anything important afak).
> > adjtime, asound.state. - Find is your friend.
> I'm not certain about these. adjtime always struck me as misplaced in /etc and
> I don't know what asound.state is and don't have one, but from the name it
> certainly sounds like it belongs elsewhere.
Do you use alsa for sound? I think asound.state comes from alsa, and
if it changes it should probably (imo) be better placed in /var/ .
It would be very nice having a fully functional system with root mounted
readonly, so please report what's needed if you succeed.