Tape Requirements for the Daily Cumulative, Weekly Incremental Backup Schedule

With this schedule, you need six tapes, if you want to reuse daily tapes, or nine tapes, if you want to use four different daily tapes: one tape for the level 0, four tapes for Fridays, and one or four daily tapes.

If you need to restore a complete file system, you need the following tapes: the level 0, all the Friday tapes, and the most recent daily tape since the last Friday tape, if any.