2 tape drives to speed up backup?

[Akira_Kato]

I have a server with an autoloader and an Ultrium 2 tape drive which backs up itself and 6 other servers. The total data size is over 400GB and each daily full backup spans 2 tapes and takes 15 hours. In order to speed up the backup process, we are considering different options. I could run incremental backups during the week. I could purchase a larger capacity tape drive.

Does anyone use 2 identical tape drives and run 2 simultaneous backup jobs? I can split the current backup job into 2 parts one for each drive. Would that speed up the whole backup process enough to consider? Unfortunately we don't have extra tape drives to actually try this.

I just wanted to know if this was a viable option or not. I would appreciate any thought.

[Gauri_Ketkar]

Hi,

-If you are going to purchase one more tape drive then you can start 2 seperate jobs on 2 seperate drives. That will reduce the backup time .

Do you have cascaded drives ?

Update us on the same and revert for any further Query
Hope this will help you


Thank you
Gauri


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[Ken_Putnam]

This is somewhat dated now, but at one point I had six DLT7000s hanging off three dedicated SCSI channels on a PII/400. All six running at one time or individually, there was negligible difference in throughput

[Akira_Kato]

My other question was whether there would be much gain in speed by having 2 SCSI cards (one for each tape drive) as opposed to having both drives connected to a single SCSI card.

We don't have 2 drives (or 2 SCSI cards) for the server we are considering this possible solution for. We have however, tried 2 different kinds of tape drives on a test server: an Ultrium 1 and a DAT drive both connected to a single SCSI card. We compared running the whole backup on the Ultrium drive alone and splitting it into 2 simultaneous backups running on the Ultrium drive and the DAT drive. Unfortunately we didn't see any difference in total backup duration since the DAT drive is much slower than the Ultrium drive.

Were you able to reduce the time by running 6 tape drives, Ken?

[Ken_Putnam]

if you are using a dedicated SCSI controller for your tape drive(s), to maximize throughput, you could place one drive on each channel, but probably would not see much improvement over two drives on the same channel

Three drives on the same SCSI channel would most likely be slower than two on one channel and the third on the second

[shweta_rege]

Hello Akira,


- Could you please Update us on the issue?


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Thanks.