On Thu, Aug 27, 2015 at 11:18 AM, Mike Aubury <m...@aubit.com> wrote: > Offlist - thanks for the help so far..
No, I'm changing it back to onlist. It's not appropriate to take this offlist. This whole conversation is relevant to others who end up in this same situation. And the ReadyNAS folks should have better support for this, you paid them money for this product, and it was their choice to use Btrfs. They should support you. But in the meantime the Btrfs list is the right place for the discussion. > > > The loop device is still there > > # losetup -a > /dev/loop0: [0861]:198 (/media/USB_HDD_1/t1/tmpbtrfs) > > But doesnt seem to be being picked up : > > # btrfs fi show > warning devid 4 not found already > Label: '0e36d290:data' uuid: e75a9856-d9e5-4d02-92e6-a217056c69b7 > Total devices 4 FS bytes used 6.09TiB > devid 1 size 2.71TiB used 2.71TiB path /dev/md127 > devid 2 size 1.82TiB used 1.82TiB path /dev/md126 > devid 3 size 1.82TiB used 1.82TiB path /dev/md125 > *** Some devices missing Try # btrfs dev scan > Trying a mount in that state gives : > > # mount /data > mount: wrong fs type, bad option, bad superblock on /dev/md126, > missing codepage or helper program, or other error > In some cases useful info is found in syslog - try > dmesg | tail or so > > dmesg gives : > btrfs: failed to read chunk tree on md125 > btrfs: open_ctree failed If dev scan doesn't work you could try to mount with -o ro,degraded but I do not recommend it until you fist explore all options to make btrfs aware of this loop back device. In the future I think it's better to use the USB stick directly rather than loopback files which just adds more complexity to an already fragile situation. > FWIW - When I used the usb file - it never had any "usage" reported in > the "fi show" - used was always 0GB, I think the thing is just totally > messed up, and all i've done is mess it up more! There is at least some metadata on it, or it wouldn't be get fussy that the device is missing. So you need to get the loop back device visible to Btrfs and then it will almost certainly mount at least ro at which point you can get data off of it first; and then you can deal with the btrfs dev delete part. -- Chris Murphy -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
