ADSM is an incremental backup system. It backs up only the changed files every night, and maintains an image on the server of the state of the filesystem. It is only possible to restore the filesystem to its current image state, although it is possible to restore older versions of deleted files. The ADSM backup runs nightly, starting immediately after midnight on ADSM client machines. ADSM maintains backup data for both and active and inactive files.
Active files are files that exist in the filesystem being backed up.
Inactive files are files that have been deleted from the filesystem. Up to thirty versions of an active file are retained for up to 30 days. For files that are changing, this would mean that the oldest copy available would be thirty days old. Inactive files are kept for a maximum of one year, but only the most recent version is retained. Any versions of inactive files that are older than one year are released.