20.04.2018 17:31, Paul Neuwirth пишет:
On Friday 2018-04-20 15:08, Andrei Borzenkov wrote:
On Fri, Apr 20, 2018 at 2:22 PM, Paul Neuwirth <mail@paul-neuwirth.nl> wrote:
Hello, web search without X11 is difficult.. Anyone knows how I can boot into openSUSE (Leap 42.3) on a btrfs root filesystem, which got degraded. I wanted to exchange a defective harddisk.
Do you have RAID1? Otherwise what's the point in booting into something that you are going to replace anyway.
I am sorry, it is of course RAID Level 1.
OK, that was expected. As a side note, multi-device btrfs is not really supported by YaST (and installer).
One HDD is ok, the other has bad sectors.
I tried booting with rootflags=degraded, and also specifying root partition as "root=/dev/sdb2". despite that, boot doesn't even complete to rescue mode, but is waitin without limit with "A start job is running for dev-whatever.device"
Well, if device is not there, then even degraded mount is not possible.
the second device is not needed to mount it degraded. But systemd is awaiting it anyway. Despite of the rootflags.
There are two problems 1. Integration of multi-device btrfs in systemd startup sequence is rudimentary at best. It requires that all devices are seen once and there is no provision for overriding it and booting in degraded state. 2. Such automatic degraded mount would actually be quite dangerous, at least with relatively old kernel used by Leap 42.x. btrfs raid1 gives you exactly one chance to fix it by replacing device. If this single attempt is unsuccessful for whatever reason, filesystem goes in permanent read-only state where you can no more do anything beyond copying data off it and recreating. I believe this is fixed in 4.15. So find yourself live Linux with as recent kernel and btrfs programs as possible and fix your RAID1 from there. -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org