I just tested to boot with a single drive (raid1 degraded), even with degraded option in fstab and grub, unable to boot ! The boot process stop on initramfs. Is there a solution to boot with systemd and degraded array ? Thanks -- Christophe Yayon > On 27 Jan 2018, at 07:48, Christophe Yayon <cyayon@xxxxxxxx> wrote: > > I think you are right, i do not see any systemd message when degraded option is missing and have to remount manually with degraded. > > It seems it is better to use mdadm for raid and btrfs over it as i understand. Even in recent kernel ? > I hav me to do some bench and compare... > > Thanks > > -- > Christophe Yayon > >> On 27 Jan 2018, at 07:43, Andrei Borzenkov <arvidjaar@xxxxxxxxx> wrote: >> >> 27.01.2018 09:40, Christophe Yayon пишет: >>> Hi, >>> >>> I am using archlinux with kernel 4.14, there is btrfs module in initrd. >>> In fstab root is mounted via UUID. As far as I know the UUID is the same >>> for all devices in raid array. >>> The system boot with no problem with degraded and only 1/2 root device. >> >> Then your initramfs does not use systemd. >> >>> -- >>> Christophe Yayon >>> cyayon-list@xxxxxxxx >>> >>> >>> >>>>> On Sat, Jan 27, 2018, at 06:50, Andrei Borzenkov wrote: >>>>> 26.01.2018 17:47, Christophe Yayon пишет: >>>>> Hi Austin, >>>>> >>>>> Thanks for your answer. It was my opinion too as the "degraded" >>>>> seems to be flagged as "Mostly OK" on btrfs wiki status page. I am >>>>> running Archlinux with recent kernel on all my servers (because of >>>>> use of btrfs as my main filesystem, i need a recent kernel).> > >>>>> Your idea to add a separate entry in grub.cfg with >>>>> rootflags=degraded is attractive, i will do this...> > >>>>> Just a last question, i thank that it was necessary to add >>>>> "degraded" option in grub.cfg AND fstab to allow boot in degraded >>>>> mode. I am not sure that only grub.cfg is sufficient...> > Yesterday, i have done some test and boot a a system with only 1 of >>>>> 2 drive in my root raid1 array. No problem with systemd,> >>>> Are you using systemd in your initramfs (whatever >>>> implementation you are> using)? I just tested with dracut using systemd dracut module and it >>>> does not work - it hangs forever waiting for device. Of course, >>>> there is> no way to abort it and go into command line ... >>>> >>>> Oh, wait - what device names are you using? I'm using mount by >>>> UUID and> this is where the problem starts - /dev/disk/by-uuid/xxx will >>>> not appear> unless all devices have been seen once ... >>>> >>>> ... and it still does not work even if I change it to root=/dev/sda1 >>>> explicitly because sda1 will *not* be announced as "present" to >>>> systemd> until all devices have been seen once ... >>>> >>>> So no, it does not work with systemd *in initramfs*. Absolutely. >>> >>> >> > > -- > To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
