Provided by: btrfs-tools_4.4-1_amd64
btrfs-select-super - overwrite superblock with a backup
btrfs-select-super -s number dev
btrfs-select-super destructively overwrites all copies of the superblock with a specified copy. This helps with certain cases of damage, especially when barriers were disabled during a power failure. You can find a valid copy of the superblock with btrfs check -s. The filesystem specified by dev must not be mounted.
-s|--super <superblock> use <superblock>th superblock copy, valid values are 0 up to 2 if the respective superblock offset is within the filesystem