Checking and Recovery
Unix systems traditionally rely on "fsck" programs to check and repair filesystems. The "btrfsck" program is now available but, as of May 2012, it is described by the authors as "relatively new code" which has "not seen widespread testing on a large range of real-life breakage", and that "may cause additional damage in the process of repair".
There is another tool, named btrfs-restore, that can be used to recover files from an unmountable filesystem, without modifying the broken filesystem itself (i.e., non-destructively).
In normal use Btrfs is mostly self healing and can recover from broken root trees at mount time since a backup is made every 30 seconds. Thus isolated errors will cause a maximum of 30 seconds of filesystem changes to be lost at next mount. This period can be changed.
Famous quotes containing the word recovery:
“It’s even pleasant to be sick when you know that there are people who await your recovery as they might await a holiday.”
—Anton Pavlovich Chekhov (1860–1904)