This policy refers to backups of user account data. User data is stored on the Unix servers, Andromeda and Pegasus.
Periodically, backup copies of this data are saved onto tapes. Being able to restore user account data is useful in case offal system failure, or in the case of a user accidentally erasing one of their files. This policy refers to the retention of backup tapes.

Daily & Weekly Backups

Daily backups for user data are kept at restore points going back each night for 5 nights, then each weekend for 8 weeks using a backup system between Unix servers. Daily backups going back 8 weeks are also kept on tape backup separate from the Unix server backups.

No backups are saved beyond 8 weeks.
All backup tapes are recycled back into use after the 8 week cycle.

If a user deletes a file in their account on purpose or by accident, that file can be recovered from the backups for a period of up to 8 weeks.  Beyond 8 weeks from the time the file was dieted, that file can not be recovered fro backups. Files which gaffe not deleted from a user's account, are kept for as long as their account is kept active.

Systems and Log Files

System files and log files, may be retained for up to one year for proper administration of systems and statistical analysis of log data.  The above policy holds for all NCS Unix servers.