Abstract

StoreBackup is a disk-to-disk backup tool for GNU/Linux. It also runs on other Unix-like machines. You can directly browse through the backed-up files (locally or via NFS, Samba, SSH⁵ or almost any other network file system). This gives the users the ability to restore files easily and quickly. The user only has to copy (and optionally uncompress) the files to restore them. There is also a tool for easy restoring (sub-) trees for the administrator. Every single backup from a specific time can be deleted without affecting the other existing backups.

StoreBackup recognizes files by their content rather than just by their name or location. It detects if files have been copied, renamed or moved. If the file is identical, but differs by name or location, storeBackup has an efficient way (hardlinks) to include that file in the current backup without copying it again. When a user reorganizes his photo or music collection, most backup software must transfer all those files over the network and store them again in the backup location, wasting time and space. StoreBackup will simply hardlink to the identical content that is already stored in the backup location, saving a lot of time and space.

StoreBackup can split big image files (e.g., from virtual machines) in little pieces and needs only the space for changes in these splits. Restoring these parts to the full image is also easily possible with simple tools: cat or possibly bzcat (or whatever you used for compression). Naturally, storeBackup delivers a tool to restore everything easier. You can also split devices or partitions (like /dev/sdb1) in the same way.

StoreBackup offers itself to the general user who does not necessarily own a tape backup but a second hard drive or another computer. It also offers itself to the users in the professional environment for extremely fast and comfortable access to their backups, also to save on the costs of tapes as well as administrative expenses.

StoreBackup is a command line tool. You can start it via cron automatically. Normally, you would not want to have a graphical surface on a server and most important: If your machine crashed, you probably do not have a running gui.

Storage on hard drives, memory sticks or similar devices offers itself as an alternative or additional resource to data backup on tapes. StoreBackup performs well, saves storage capacity, and increases administrative flexibility:

• Directories, including their tree structure, may be copied to another location
  (e.g. /home $\longrightarrow$ /var/bkup/2003.12.13_02.04.26). Permissions to the files remain, enabling users to access the backup directly. The most important aspect of a backup tool is easy and safe restoring.
• The content of each file being backed up is compared with the existing backup to make sure there is only one backup for each file. That means files with the same content exist physically only once in the backup.
• Identical files are hard linked and appear in the backup in the same locations as in the original.
• You can exclude files from the backup by excluding whole directories or by specifying rules depending on regular expressions, file size, groups, users and other criteria.
• Backed up files will be compressed, unless they are marked 'exclude'. Compression may also be excluded entirely or may be the result of a file based analysis of storeBackup itself.
• Image files or mass storage devices, where only parts change from backup to backup can be evaluated for differences. In the backup, you will only need the space for the changed blocks (which can be compressed).
• Backup series, generated independently (e.g. from different machines) may refer through hard links to shared files. Full or partial backups may be executed with this method, always under the condition that files with the same content may exist only once in the backup.
• The final result of running storeBackup is always a full backup. This can be automatically deleted with easy or high sophisticated deletion rules.
• StoreBackup supports a lot of other options. They are described in this document.