* unable to mount disk? @ 2021-09-28 18:44 Matt Zagrabelny 2021-09-28 18:59 ` Chris Murphy 0 siblings, 1 reply; 4+ messages in thread From: Matt Zagrabelny @ 2021-09-28 18:44 UTC (permalink / raw) To: linux-btrfs Greetings btrfs folks, I am attempting to mount a filesystem on a (likely) failing disk: $ mount /var/local/media mount: /var/local/media: wrong fs type, bad option, bad superblock on /dev/sdb, missing codepage or helper program, or other error. excerpt from dmesg: [ 352.642893] BTRFS info (device sdb): disk space caching is enabled [ 352.642897] BTRFS info (device sdb): has skinny extents [ 352.645562] BTRFS error (device sdb): devid 2 uuid bf09cc8f-44d6-412e-bc42-214ff122584a is missing [ 352.645570] BTRFS error (device sdb): failed to read the system array: -2 [ 352.646770] BTRFS error (device sdb): open_ctree failed Is there anything I can do to attempt to recover this hardware issue? Thanks, -m ^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: unable to mount disk? 2021-09-28 18:44 unable to mount disk? Matt Zagrabelny @ 2021-09-28 18:59 ` Chris Murphy 2021-09-28 19:23 ` Matt Zagrabelny 0 siblings, 1 reply; 4+ messages in thread From: Chris Murphy @ 2021-09-28 18:59 UTC (permalink / raw) To: Matt Zagrabelny; +Cc: Btrfs BTRFS On Tue, Sep 28, 2021 at 2:53 PM Matt Zagrabelny <mzagrabe@d.umn.edu> wrote: > > Greetings btrfs folks, > > I am attempting to mount a filesystem on a (likely) failing disk: > > $ mount /var/local/media > mount: /var/local/media: wrong fs type, bad option, bad superblock on > /dev/sdb, missing codepage or helper program, or other error. > > excerpt from dmesg: > > [ 352.642893] BTRFS info (device sdb): disk space caching is enabled > [ 352.642897] BTRFS info (device sdb): has skinny extents > [ 352.645562] BTRFS error (device sdb): devid 2 uuid > bf09cc8f-44d6-412e-bc42-214ff122584a is missing > [ 352.645570] BTRFS error (device sdb): failed to read the system array: -2 > [ 352.646770] BTRFS error (device sdb): open_ctree failed > > Is there anything I can do to attempt to recover this hardware issue? This is a 2+ device Btrfs file system? And one of the devices, devid2, is missing. So you need to figure out why. If the drive has in fact failed, rather than just missing power/data connection, you can mount degraded using the 'degraded' mount option. Just be advised that there are potentially some consequences to operating under degraded mode, depending on the specific configuration. -- Chris Murphy ^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: unable to mount disk? 2021-09-28 18:59 ` Chris Murphy @ 2021-09-28 19:23 ` Matt Zagrabelny 2021-09-29 1:10 ` Chris Murphy 0 siblings, 1 reply; 4+ messages in thread From: Matt Zagrabelny @ 2021-09-28 19:23 UTC (permalink / raw) To: Btrfs BTRFS On Tue, Sep 28, 2021 at 1:59 PM Chris Murphy <lists@colorremedies.com> wrote: > > On Tue, Sep 28, 2021 at 2:53 PM Matt Zagrabelny <mzagrabe@d.umn.edu> wrote: > > > > Greetings btrfs folks, > > > > I am attempting to mount a filesystem on a (likely) failing disk: > > > > $ mount /var/local/media > > mount: /var/local/media: wrong fs type, bad option, bad superblock on > > /dev/sdb, missing codepage or helper program, or other error. > > > > excerpt from dmesg: > > > > [ 352.642893] BTRFS info (device sdb): disk space caching is enabled > > [ 352.642897] BTRFS info (device sdb): has skinny extents > > [ 352.645562] BTRFS error (device sdb): devid 2 uuid > > bf09cc8f-44d6-412e-bc42-214ff122584a is missing > > [ 352.645570] BTRFS error (device sdb): failed to read the system array: -2 > > [ 352.646770] BTRFS error (device sdb): open_ctree failed > > > > Is there anything I can do to attempt to recover this hardware issue? > > > This is a 2+ device Btrfs file system? And one of the devices, devid2, > is missing. So you need to figure out why. If the drive has in fact > failed, rather than just missing power/data connection, you can mount > degraded using the 'degraded' mount option. Just be advised that there > are potentially some consequences to operating under degraded mode, > depending on the specific configuration. Thanks for the hints, Chris. Appreciated. What sort of potential consequences are we talking about, if you could elaborate? Cheers, -m ^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: unable to mount disk? 2021-09-28 19:23 ` Matt Zagrabelny @ 2021-09-29 1:10 ` Chris Murphy 0 siblings, 0 replies; 4+ messages in thread From: Chris Murphy @ 2021-09-29 1:10 UTC (permalink / raw) To: Matt Zagrabelny; +Cc: Btrfs BTRFS On Tue, Sep 28, 2021 at 3:23 PM Matt Zagrabelny <mzagrabe@d.umn.edu> wrote: > > On Tue, Sep 28, 2021 at 1:59 PM Chris Murphy <lists@colorremedies.com> wrote: > > > > On Tue, Sep 28, 2021 at 2:53 PM Matt Zagrabelny <mzagrabe@d.umn.edu> wrote: > > > > > > Greetings btrfs folks, > > > > > > I am attempting to mount a filesystem on a (likely) failing disk: > > > > > > $ mount /var/local/media > > > mount: /var/local/media: wrong fs type, bad option, bad superblock on > > > /dev/sdb, missing codepage or helper program, or other error. > > > > > > excerpt from dmesg: > > > > > > [ 352.642893] BTRFS info (device sdb): disk space caching is enabled > > > [ 352.642897] BTRFS info (device sdb): has skinny extents > > > [ 352.645562] BTRFS error (device sdb): devid 2 uuid > > > bf09cc8f-44d6-412e-bc42-214ff122584a is missing > > > [ 352.645570] BTRFS error (device sdb): failed to read the system array: -2 > > > [ 352.646770] BTRFS error (device sdb): open_ctree failed > > > > > > Is there anything I can do to attempt to recover this hardware issue? > > > > > > This is a 2+ device Btrfs file system? And one of the devices, devid2, > > is missing. So you need to figure out why. If the drive has in fact > > failed, rather than just missing power/data connection, you can mount > > degraded using the 'degraded' mount option. Just be advised that there > > are potentially some consequences to operating under degraded mode, > > depending on the specific configuration. > > Thanks for the hints, Chris. Appreciated. > > What sort of potential consequences are we talking about, if you could > elaborate? > > Cheers, > > -m If it's a 2 disk raid1, and one device dies, and you mount -o degraded - it's no longer possible for btrfs to create raid1 block groups, because that profile requires creating a mirrored pair of chunks which can't happen because there's only one device. It's possible some data will write to existing raid1 chunks, but other data can cause new single chunks to be created. The data in these block groups won't automatically be replicated when you do 'btrfs replace' to replace the failed device, or if you fix the device problem and it rejoins the working drive, a scrub won't catch up the stale drive either. You will have to do 'btrfs balance start -dconvert=raid1,soft -mconvert=raid1,soft" to make sure the single profile block groups are converted to raid1 block groups. -- Chris Murphy ^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2021-09-29 1:10 UTC | newest] Thread overview: 4+ messages (download: mbox.gz / follow: Atom feed) -- links below jump to the message on this page -- 2021-09-28 18:44 unable to mount disk? Matt Zagrabelny 2021-09-28 18:59 ` Chris Murphy 2021-09-28 19:23 ` Matt Zagrabelny 2021-09-29 1:10 ` Chris Murphy
This is an external index of several public inboxes, see mirroring instructions on how to clone and mirror all data and code used by this external index.