Linux Server Hacks, Volume Two

Hack #95. Repair and Recover ReiserFS Filesystems

Different filesystems have different repair utilities and naming conventions for recovered files. Here's how to repair a severely damaged ReiserFS filesystem.

"Recover Data from Crashed Disks" [Hack #94] explained how to use the ddrescue utility to clone a disk or partition that you could not check the consistency of or read, and how to use the ext2/ext3 e2fsck utility to check and correct the consistency of the cloned disk or partition. This hack explains how to repair and recover severely damaged ReiserFS filesystems.

The ReiserFS filesystem was the first journaling filesystem that was widely used on Linux systems. Journaling filesystems such as ext3, JFS, ReiserFS, and XFS save pending disk updates as atomic transactions in a special on-disk log, and then asynchronously commit those updates to disk, guaranteeing filesystem consistency at any given point. Developed by a team led by Hans Reiser, ReiserFS incorporates many of the cutting-edge concepts of the time into a stable journaling filesystem that is the default filesystem type on Linux distributions such as SUSE. For more information about the ReiserFS filesystem, see its home page at http://www.namesys.com.

ReiserFS filesystems have their own utility, reiserfsck, which provides special options for repairing and recovering severely damaged ReiserFS filesystems. Like fsck, the reiserfsc utility uses a lost+found directory, located at the root of the filesystem, to store undamaged ...