As you have an additional slot for the new disk, the proper procedure
would have been
btrfs replace start -r <faulty-dev> <new-dev> /mnt
-r shall avoid reading from the faulty dev.
(In some cases there might not be any spare slots, I am looking into
fixing replace command for those cases.)
Thanks, Anand
On 19/7/20 10:13 pm, Edmund Urbani wrote:
Hello everyone,
after having RMA'd a faulty HDD from my RAID6 and having received the
replacement, I added the new disk to the filesystem. At that point the
missing device was still listed and I went ahead to remove it like so:
btrfs device delete missing /mnt/shared/
After a few hours that command aborted with an I/O error and the logs
revealed this problem:
[284564.279190] BTRFS info (device sda1): relocating block group
51490279391232 flags data|raid6
[284572.319649] btrfs_print_data_csum_error: 75 callbacks suppressed
[284572.319656] BTRFS warning (device sda1): csum failed root -9 ino 433
off 386727936 csum 0x791e44cc expected csum 0xbd1725d0 mirror 2
[284572.320165] BTRFS warning (device sda1): csum failed root -9 ino 433
off 386732032 csum 0xec5f6097 expected csum 0x9114b5fa mirror 2
[284572.320211] BTRFS warning (device sda1): csum failed root -9 ino 433
off 386736128 csum 0x4d2fa4b9 expected csum 0xf8a923f9 mirror 2
[284572.320225] BTRFS warning (device sda1): csum failed root -9 ino 433
off 386740224 csum 0xcad08362 expected csum 0xa9361ed3 mirror 2
[284572.320266] BTRFS warning (device sda1): csum failed root -9 ino 433
off 386744320 csum 0x469ac192 expected csum 0xb1e94692 mirror 2
[284572.320279] BTRFS warning (device sda1): csum failed root -9 ino 433
off 386748416 csum 0x69759c1f expected csum 0xb3b9aa86 mirror 2
[284572.320290] BTRFS warning (device sda1): csum failed root -9 ino 433
off 386752512 csum 0xd3a7c5d5 expected csum 0xd351862f mirror 2
[284572.320465] BTRFS warning (device sda1): csum failed root -9 ino 433
off 386756608 csum 0x1264af83 expected csum 0x3a2c0ed5 mirror 2
[284572.320480] BTRFS warning (device sda1): csum failed root -9 ino 433
off 386760704 csum 0x260a13ef expected csum 0xb3b4aec0 mirror 2
[284572.320492] BTRFS warning (device sda1): csum failed root -9 ino 433
off 386764800 csum 0x6b615cd9 expected csum 0x99eaf560 mirror 2
I ran a long SMART self-test on the drives in the array which found no
problem. Currently I am running scrub to attempt and fix the block group.
scrub status:
UUID: 9c3c3f8d-a601-4bd3-8871-d068dd500a15
Scrub started: Fri Jul 17 07:52:06 2020
Status: running
Duration: 14:47:07
Time left: 202:05:46
ETA: Tue Jul 28 00:07:36 2020
Total to scrub: 16.80TiB
Bytes scrubbed: 1.14TiB
Rate: 22.56MiB/s
Error summary: read=295132162
Corrected: 0
Uncorrectable: 295132162
Unverified: 0
device stats:
Label: none uuid: 9c3c3f8d-a601-4bd3-8871-d068dd500a15
Total devices 5 FS bytes used 16.80TiB
devid 3 size 9.09TiB used 8.76TiB path /dev/sda1
devid 4 size 9.09TiB used 8.76TiB path /dev/sdb1
devid 5 size 9.09TiB used 8.74TiB path /dev/sdd1
devid 6 size 9.09TiB used 498.53GiB path /dev/sdc1
*** Some devices missing
Is there anything else I can do to try and specifically fix that one
block group rather than scrubbing the entire filesytem? Also, is it
"normal" that scrub stats would show a huge number of "uncorrectable"
errors when a device is missing or should I be worried about that?
Kind regards,
Edmund
