DirSync is a directory synchronizer that takes a source and destination directory as arguments and recursively ensures that the two directories are identical. It can be used to create incremental copies of large chunks of data. For example, if your file server's contents are in the directory /data, you can make a copy in a directory called /backup with the command "dirsync /data /backup." The first time you run it, all data will be copied. On subsequent runs, only the changed files are copied.
The dsnapshot script provides a high-level interface to the Linux Logical Volume Manager. It uses its block-level snapshot support to create directory snapshots. In contrast to block-level snapshots, directory snapshots resemble the file system layer. Thus, you can snapshot any directory that is on a logical volume without worrying about the actual logical volumes, mount points, and paths.
DiscSpan is a tool that will take that a large directory full of files and automatically burn a series of DVDs to near capacity, without the need or hassle of creating individual ISOs or moving files around. It is geared more towards smaller files such as music and photos, as it cannot span a file across multiple discs. It prompts for the directory you'd like to back up, the device to use to burn, and the speed at which to burn. It analyzes the files and calculates how many DVDs are needed, while making sure no files are greater than the size of a DVD.
Dar is a shell command that makes backup of a directory tree and files. Its features include splitting archives over several files, DVD, CD, ZIP, or floppies, compression, full or differential backups, strong encryption, proper saving and restoration of hard links, extended attributes, file forks, Door inodes, and sparse files, remote backup using pipes and external commands (such as ssh), and rearrangement of the "slices" of an existing archive. It can run commands between slices, before and after saving some defined files or directories (for a proper database backup, for example), and quickly retrieve individual files from differential and full backups. Several external GUIs exist as alternatives to its CLI interface, like kdar, DarGUI, SaraB, etc.
DiskSearch is a tool for searching for files on all your removable media disks, including CDs, ZIP disks, and backup tapes. It allows you to search for songs on your MP3 CDs or for a document on your backup DVDs. For advanced queries, a regular expression search mode is provided. Searches are based on a simple database file, which needs to be filled once by adding all your disks to it.
The dump package contains both dump and restore. Dump examines files in a filesystem, determines which ones need to be backed up, and copies those files to a specified disk, tape or other storage medium. The restore command performs the inverse function of dump; it can restore a full backup of a filesystem. Subsequent incremental backups can then be layered on top of the full backup. Single files and directory subtrees may also be restored from full or partial backups.