On Thu, Jul 3, 2014 at 2:14 PM, Zbigniew Jędrzejewski-Szmek <zbys...@in.waw.pl> wrote: > 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
Hm, the only way this would get re-fscked in the system is if it is explicitly configured to be in /etc/fstab... Shouldn't we just give people what they ask for? Otherwise passno= for the rootfs would have no effect at all in this setup (the rootfs is fscked unconditionally in the initrd regardless of what /etc/fstab says (obviously)). >> 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 _______________________________________________ systemd-devel mailing list systemd-devel@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/systemd-devel
