On Thu, Jul 03, 2014 at 11:49:20AM +0200, Thomas Bächler wrote: > Am 02.07.2014 14:29, schrieb Daniel Drake: > > If I'm reading things right, actually the default behaviour is (when > > no hints are supplied in kernel cmdline) : > > 1. systemd runs fsck on root from initramfs > > 2. systemd mounts root fs ro > > 3. switch-root onto real system > > 4. systemd-fsck-root runs > > 5. systemd-remount-fs remounts / as rw > > > > Also just noticed another interesting thing - > > systemd-fsck-root.service is only loaded dynamically, when /etc/fstab > > has a non-zero passno for /. So maybe the idea is that anyone running > > a regular and modern dracut/systemd setup sets passno=0 for / in > > fstab, with the knowledge that fsck of / is done by the initramfs. > > Tom and me are thought this through a couple of months ago when I > started looking into using Arch's mkinitcpio with systemd. We submitted > a few changes to fsck handling back then. > > This is the setup we want to support (this is now the default in a new > Arch installation): > 1) fsck in initramfs > 2) initramfs mounts rw > 3) no re-fsck in the system This is what we want.
We also want this to work: 1) fsck in the initramfs 2) initramfs mounts ro 3) no re-fsck or remount in the system > This is still supported, for legacy systems that have not been > reconfigured properly: > 1) no fsck in initramfs, or no initramfs > 2) initramfs or kernel mount ro > 3) fsck in the system > 4) remount rw in the system > > > This setup works, but is not optimal: > 1) fsck in initramfs > 2) initramfs mounts ro > 3) re-fsck in the system > 4) remount rw in the system > In this case, I always recommend mounting rw right away. However, you > can also configure your fstab to skip fsck - I don't see why anyone > would prefer this though. > > For your read-only case, you have two options: > > * Have an fstab entry for / with passno=0 > * Don't list / in fstab > > I prefer the last option, since there is no benefit in adding / to fstab > - IMO, the correct mount options should always be given via the kernel > commandline to make remounting unnecessary. > > In my opinion, there is no need to change anything in systemd here, > since all the right configuration options are already there. You're right that everything *can* be configured to work properly. But if any fs was already checked in the initramfs, systemd should be always smart enough to avoid checking it again in the main system. I think that this is works for all filesystems except root. For root it breaks when the fs is mounted ro when transitioning to main system. Zbyszek _______________________________________________ systemd-devel mailing list systemd-devel@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/systemd-devel
