ReadyNAS OS6 6.1.6 btrfs disk errors

Ok, as I thought would happen and not happen...

I ran a btrfs disk check on the un-mounted /data directory in repair mode which took 6 hours to complete and once complete did not fix any of the errors. As I stated before I had this problem on another system with same result.

btrfsck --repair /dev/mapper/data-0

So, since that did not work I just removed all snapshots. I made sure I removed them in order of newest first so btrfs would not have to work so hard.

# - Edit /etc/fstab and enable /data mount point
mount /data
cd /data/._share

#   (it looks like we are listing oldest first; we are but the for loop will process newest first)
for f in `ls -tdS */.snapshot/?_*`; do btrfs subvolume delete $f; done

# - Wait till load is really low and all btrf_cleaner, etc tasks complete before checking if it worked (took maybe an hour)

# - Do a filesystem check again to see if errors have been fixed
cd /
umount /data

# - Check disk again
btrfsck /dev/mapper/data-0

My disk check came back clean this time. I just canceled it after seeing extents were good now.

root@NAS:/# btrfsck /dev/mapper/data-0 
Checking filesystem on /dev/mapper/data-0
UUID: d2d2b9e8-9acb-4fd9-8152-9c7c0bebc294
checking extents
checking free space cache

So, I just rebooted the NAS

rn_shutdown -r

I hope the btrfs guys take care of this in the check disk utility since this has happened to me more than once in the last few weeks on 2 seperate linux systems. I know they know about it since I seen another user have same problem which he could only fix by re-formatting (did not look like he tried removing snapshots first like I did).

I actually wonder how many users whose systems crahed have these errors and don't even know they have them since the btrfs filesystem does not get checked on boot?

Anyway, I'm happy again :)