Re: [REQ] Help to gain access to btrfsraid6 pool that won't mount

[TheJay <obiwantje@gmail.com>]

On Tue, 05 May 2015 00:52:16 -0600, Chris Murphy wrote:

> On Mon, May 4, 2015 at 3:36 PM, TheJay <obiwantje@gmail.com> wrote:
> 
>> [Mon May  4 14:33:17 2015] BTRFS: bdev (null) errs: wr 3, rd 28773, flush 2, corrupt 0, gen 0
> 
> So there might be more than one thing going wrong and they're
> colliding to make a worse problem. You've got three write and 2 flush
> errors, and many thousands of read errors (probably due to missing
> devices).
> 
> It might be worth trying -o degraded,recovery because recovery can't
> work with devices missing, and degraded alone won't run the recovery
> code.
> 
> 
> -- 
> Chris Murphy

$ mount  -o degraded,recovery /dev/sdz /mnt/roms03
mount: wrong fs type, bad option, bad superblock on /dev/sdy,
       missing codepage or helper program, or other error
       In some cases useful info is found in syslog - try
       dmesg | tail  or so

$ dmesg -T|tail
[Tue May  5 00:26:01 2015] BTRFS info (device sdaa): enabling auto recovery
[Tue May  5 00:26:01 2015] BTRFS info (device sdaa): disk space caching is enabled
[Tue May  5 00:26:01 2015] BTRFS: has skinny extents
[Tue May  5 00:26:01 2015] BTRFS: bdev (null) errs: wr 3, rd 28773, flush 2, corrupt 0, gen 0
[Tue May  5 00:26:05 2015] BTRFS (device sdaa): bad tree block start 8714499618262386624 1585233920
[Tue May  5 00:26:05 2015] BTRFS (device sdaa): bad tree block start 8714499618262386624 1585233920
[Tue May  5 00:26:05 2015] BTRFS (device sdaa): bad tree block start 8714499618262386624 1585233920
[Tue May  5 00:26:05 2015] BTRFS (device sdaa): bad tree block start 8714499618262386624 1585233920
[Tue May  5 00:26:05 2015] BTRFS: Failed to read block groups: -5
[Tue May  5 00:26:06 2015] BTRFS: open_ctree failed