backup and restore for ext2/3/4 filesystems

 This is a port of the 4.4BSD filesystem backup suite.
 Dump examines files on a filesystem and determines which files need to be
 backed up. These files are copied to the given disk, tape or other storage
 medium for safe keeping.
 .
 The restore command performs the inverse function of dump. A full backup of
 a filesystem may be restored and subsequent incremental backups layered on
 top of it. Single files and directory subtrees may be restored from full or
 partial backups.