On Mon, Nov 11, 2019 at 2:44 AM Paul Monsour <boulos@xxxxxxx> wrote: > > parted -l produced: > > Model: ATA ST3000DM008-2DM1 (scsi) > Disk /dev/sdc: 3001GB > Sector size (logical/physical): 512B/4096B > Partition Table: gpt > Disk Flags: > Number Start End Size File system Name Flags > 1 1049kB 3001GB 3001GB btrfs Home > > Model: ATA ST3000DM008-2DM1 (scsi) > Disk /dev/sdd: 3001GB > Sector size (logical/physical): 512B/4096B > Partition Table: msdos > Disk Flags: > Number Start End Size Type File system Flags > 2 119kB 1593kB 1475kB primary esp > > The portion of the dd command that wrecked the files was "of=/dev/sdd1" OK? According to the parted output, there is a single partition number 2, therefore only /dev/sdd2 should exist and the dd command should have failed. So... something is missing in the information provided, or maybe a typo somewhere. > > btrfs restore produced just: > > drwxr-xr-x 1 root root 0 Nov 10 12:43 ftp > drwxr-xr-x 1 root root 362 Nov 10 12:51 palsor > > However, I was (perhaps optimistically) heartened by what "btrfs-find-root /dev/sdc1" produced: > > # btrfs-find-root /dev/sdc1 > warning, device 2 is missing > Superblock thinks the generation is 322292 > Superblock thinks the level is 1 > Found tree root at 649710272512 gen 322292 level 1 > > How do I use this information? Is there reason to be optimistic? No. The best possible case is data raid0, and metadata raid1, in which case the file system will mount with "degraded" option and you'll be able to recover any files that are completely on the intact device, and not subject to any striping. Otherwise they will be considered by Btrfs to be corrupt/missing, although I'm not sure if it results in EIO or something else. If metadata is also raid0, then the file system won't mount. You probably also won't have much success with btrfs restore either. -- Chris Murphy
