Tape Retention / Rewrite start with incremental Backup

[StefanMosleitner]

Hi!

If I create a Backuptask with 1full + 5 incremental Backups and the Tape is full. What happens if incremental Backup is in the queue? Tape Retention Time is over and the tape can start writting at the beginning of the tape.
-> Incremental Backup is written at the beginning of the Tape -> Restore is not possible because the initial corresponding "Full" Backup is stored at the "end" of the tape?

[SuperSAN]

We experienced this scenario before.. As our tape was full and we had scheduled an incremental backup. What happened was the incremental failed until we cleared the tap, then it make a full backup, and start doing the incremental afterwards.

[StefanMosleitner]

Hi SuperSAN!

Thanks for your experience.

How did you solve this issue?

I would like to make 1 Full Backup (Mo) + 4 Incremental Backups (Tu-Fr)

- How much tapes should I use.
- What retention time is reasonable (in combination with "Use each tape only once"?).
- Tape size? (about 25 GB full Backup / about 5 GB incremental)

Thanks a lot in advance!

Best regards,
Stefan

[SuperSAN]

If you are goin to start this fresh make sure that the tapes are clean. For the tapes size, it depends on your backup.

I found the the best way to overcome problems is to make many tapes with small
retention times and configure full backup every week.

[StefanMosleitner]

Thanks.

Now we are using the following solution...

- 2 Tapes.
- no "use tape only once".
- Tape Size Limit: larger than for 1 week necessary.
- Tape retention 1 week.

-> In my opinion this solution wasts a lot of storage but it works...

regards,
Stafan