Tape Needs

With this schedule you will need at least nine tapes: one for the level 0, four for the Fridays, and four daily tapes, assuming you reuse daily tapes each week, which is not recommended. If you save the weekly tapes for a month, you need 21 tapes.

If you need to restore the complete file system, you need six tapes: the level 0, the most recent Friday tape, and all the daily tapes for that week.