i recently set up a drive pool in single mode on my little media server. about a week later SMART started telling me that the drive was having issue and there is one bad sector. since the array is far from full i decided to remove the drive from the pool. but running
btrfs device remove /dev/sdc /mnt/pool resulted in a deadlock. everything crashed, and i had to pull the plug to reboot. once up i did a btrfs check of the drive and it reported no issues with the file system... but running the remove again results in a dead lock. i have tried running a scrub and it eventually results in a dead lock also. my system: Linux kodbox 4.13.0-38-generic #43-Ubuntu SMP Wed Mar 14 15:20:44 UTC 2018 x86_64 x86_64 x86_64 GNU/Linux btrfs version: btrfs-progs v4.12 though i have also compiled the latest btrfs from git and i get the same results. btrfs fi sh /mnt/pool Label: none uuid: cb30a848-1882-4f7f-aae1-1533f52d8783 Total devices 4 FS bytes used 6.73TiB devid 1 size 7.28TiB used 5.67TiB path /dev/sdb1 devid 2 size 1.82TiB used 219.00GiB path /dev/sdd1 devid 3 size 1.82TiB used 220.03GiB path /dev/sda1 devid 4 size 3.64TiB used 655.00GiB path /dev/sdc1 btrfs fi us /mnt/pool Overall: Device size: 14.55TiB Device allocated: 6.74TiB Device unallocated: 7.81TiB Device missing: 0.00B Used: 6.74TiB Free (estimated): 7.81TiB (min: 3.91TiB) Data ratio: 1.00 Metadata ratio: 2.00 Global reserve: 512.00MiB (used: 0.00B) Data,single: Size:6.73TiB, Used:6.72TiB /dev/sda1 216.00GiB /dev/sdb1 5.67TiB /dev/sdc1 655.00GiB /dev/sdd1 215.00GiB Metadata,RAID1: Size:8.00GiB, Used:7.25GiB /dev/sda1 4.00GiB /dev/sdb1 8.00GiB /dev/sdd1 4.00GiB System,RAID1: Size:32.00MiB, Used:768.00KiB /dev/sda1 32.00MiB /dev/sdb1 32.00MiB Unallocated: /dev/sda1 1.60TiB /dev/sdb1 1.60TiB /dev/sdc1 3.00TiB /dev/sdd1 1.60TiB smartmontools tells me this: === START OF READ SMART DATA SECTION === SMART Self-test log structure revision number 1 Num Test_Description Status Remaining LifeTime(hours) LBA_of_first_error # 1 Short offline Completed: read failure 90% 11625 1372896792 # 2 Short offline Completed: read failure 90% 11571 1372896792 # 3 Extended offline Completed: read failure 90% 11562 1372896792 # 4 Extended offline Completed without error 00% 11243 - # 5 Short offline Completed without error 00% 10702 - # 6 Conveyance offline Completed without error 00% 10702 - can i just dd if=zero of=/dev/sdc count=1 bs=16k seek=42903024 (i get the location by calculating lba * sector size / block size, so 1372896792*512/16384 which should cause the drive to correctly reallocate the sector. i think. anyway, the data is not super important, but i'd like to rescue it if i can. is there a way to get data off of one device manually and put it on another device? -- 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