>> I was looking under btrfs device, sorry about that. I do have the
>> command. I tried replace and it seemed more promising than the last
>> attempt, it wrote enough data to the new drive to overflow and break
>> my overlay. I'm trying it without the overlay on the destination
>> device, I'll report back later with the results.
It looks like replace worked!
I got the following final output:
ubuntu@btrfs-recovery:~$ sudo btrfs replace status /mnt
Started on 26.Mar 20:59:12, finished on 27.Mar 05:20:01, 0 write errs,
0 uncorr. read errs
The filesystem appears in good health, no more missing devices:
ubuntu@btrfs-recovery:~$ sudo btrfs filesystem show
Label: none uuid: 67b4821f-16e0-436d-b521-e4ab2c7d3ab7
Total devices 6 FS bytes used 5.47TiB
devid 1 size 1.81TiB used 1.71TiB path /dev/sdb
devid 2 size 1.81TiB used 1.71TiB path /dev/sde
devid 3 size 1.82TiB used 1.72TiB path /dev/sdd
devid 4 size 1.82TiB used 1.72TiB path /dev/sdc
devid 5 size 2.73TiB used 2.62TiB path /dev/sda
devid 6 size 2.73TiB used 2.62TiB path /dev/sdf
btrfs-progs v4.0
However the dmesg output shows some errors despite the 0 uncorr. read
errs reported above:
[112178.006315] BTRFS: checksum error at logical 8576298061824 on dev /dev/sda,
sector 4333289864, root 259, inode 10017264, offset 32444416, length 4096, links
1 (path: mythtv/store/4663_20150809180500.mpg)
[112178.006327] btrfs_dev_stat_print_on_error: 5 callbacks suppressed
[112178.006330] BTRFS: bdev /dev/sda errs: wr 0, rd 5002, flush 0, corrupt 16, g
en 0
And the underlying file does appear to be damaged:
ubuntu@btrfs-recovery:/mnt/@home/mythtv$ dd
if=store/4663_20150809180500.mpg of=/dev/null
dd: error reading ‘store/4663_20150809180500.mpg’: Input/output error
63368+0 records in
63368+0 records out
32444416 bytes (32 MB) copied, 1.08476 s, 29.9 MB/s
Here's some dmesg output when accessing a damaged file:
[140789.642357] BTRFS warning (device sdc): csum failed ino 10017264
off 32854016 csum 2566472073 expected csum 1193787476
[140789.642503] BTRFS warning (device sdc): csum failed ino 10017264
off 32919552 csum 2566472073 expected csum 2825707817
[140789.645768] BTRFS warning (device sdc): csum failed ino 10017264
off 32509952 csum 2566472073 expected csum 834024150
I can also see that one device has had a few errors; this is the
device that was ddrescued and recorded some errors before being
ddrescued:
[/dev/sda].write_io_errs 0
[/dev/sda].read_io_errs 5002
[/dev/sda].flush_io_errs 0
[/dev/sda].corruption_errs 153
[/dev/sda].generation_errs 0
> If you do want to use a newer one, I'd build against kernel.org, just
> because the developers only use that base. And use 4.4.6 or 4.5.
At this point I could remove the overlays and recover the filesystem
permanently, however I'm also deeply indebted to the btrfs community
and want to give anything I can back. I've built (but not installed ;)
) a straight kernel.org 4.5 w/my missing device check patch applied.
Is there any interest or value in attempting to switch to this kernel,
add/delete a device and see if I experience the same errors as before
I tried replace? What information should I gather if I do this?
-JohnF
--
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
