Autoloader tape selection

[frenaud]

We are using Backup Exec 2012 to backup multiple servers with an HP 8-drive Autoloader. We are doing a full backup on Saturdays and differential backups Monday-Friday.

Our 8 tapes hold about 1.5TB each and full backups take about 500GB and around 50-70GB per differential backup. The tape is partitionned with slots 1-6 for differentials and 7-8 for full.

Overwrite protection is set for 1 week for the full tapes and 4 weeks for differential tapes.

The problem we are having is that the the differential backups are always written on the same tape. We want to have the backups spread on the other 5 differential tapes (append). All tapes are set at infinite append. Right now, it only seems to switch tapes when the tape is full.

[ZeRoC00L]

Modify the append period. See here:

http://www.symantec.com/business/support/index?page=content&id=TECH5459

If you modify the append period to 6 days, it will not be appended for 6 days.

[frenaud]

Really? I thought that the Append Period was the duration it could be appended to and it would become non-appendable after that.

[ZeRoC00L]

Ah, sorry you are right. (was doing two things at the same time....)

But that is a setting you should configure right, modify it to 1 hour and the next day it will not be appended and backup exec will get a new tape.

[frenaud]

That's my problem. I want the tapes to be appendable so we can stack multiple differentials on the same tape. We just don't want 20 differentials on tape 1 and 2-6 empty.

I can set the append limit to 1 hour, but I'd need a way to make it appendable again after 2-3 days.

[ZeRoC00L]

Then you could partition your library, and configure specific jobs to a specific partition.

[frenaud]

Partition is currently:

Slots 1-6 = Diff

Slots 7-8 = Full

So, I'd have to partition:

Slot 1 = Monday Diff

Slot 2 = Tuesday Diff

Slot 3 = Wednesday Diff

etc...

?

[pkh]

I don't know why you want to spread out your differential backups.  Each time you append to a tape, the overwrite protection of the tape gets extended.  When you spread out your differential backups, you are making a lot of tapes not overwritable and thus consuming a lot of tapes.  It is better to use 1 tape to store all the differentials from a particular week and then use another tape for the next week.  This way your tapes get freed up faster.

[frenaud]

The company I work for bought 25 LTO-5 tapes! So we've got a major surplus.

[CraigV]

...already mentioned in the OP's original post.