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bc1410's avatar
bc1410
Level 6
2 months ago

Backing up data using 2 tapes drives at the same time

Hello

We are on NBU 10.0.0.1 - windows (one server as master/media).  We have a backup job containing like 30TB of data.  The data are MS SQL *.bak files.  We want to put this to tape. On the backup policy what is the best way to utilize 2 tape drives.  
I dont think we want to send multiple streams to the same tape drive correct?  

So the data needing backed up is on the network and its laid out like this:

\\xxx-xxxxx.com\xxx\xxx_Backups\FULL\xxx123\Prod1\
\\xxx-xxxxx.com\xxx\xxx_Backups\FULL\xxx123\Prod2\
\\xxx-xxxxx.com\xxx\xxx_Backups\FULL\xxx123\Prod3\
\\xxx-xxxxx.com\xxx\xxx_Backups\FULL\xxx123\Prod4\
\\xxx-xxxxx.com\xxx\xxx_Backups\FULL\xxx123\Prod5\
\\xxx-xxxxx.com\xxx\xxx_Backups\FULL\xxx123\Prod6\
\\xxx-xxxxx.com\xxx\xxx_Backups\FULL\xxx123\Prod7\
\\xxx-xxxxx.com\xxx\xxx_Backups\FULL\xxx123\Prod8\

I thought about splitting the 8 paths into two different policies -  this I know will use two separate tape drives.  What is the protocol or the correct attributes on a Netbackup policy (MS Windows) to set it up to use 2 tape drives instead creating 2 seperate policies?. 
If I just use one policy and have 2 streams going to one tape drive thats bad news for wear and tear on the tape drive correct?

Is there a way to have a policy where their are multiple streams going to 2 different tape drives.  Hopefully Im saying this correctly.

 

BC

  • Hi bc1410 

    This should all be doable within the one policy with some minor tweaks and checks. 

    1. In the Selections section, list each of the 8 paths (although it sounds like you already do).
    2. Make sure "Allow multiple data streams" is checked in the main attributes.
    3. Again in the main attributes, if the STU can allow more than 2 concurrent drives (and you want to limit to 2), then check the "Limit jobs per policy" option and set the value to 2. With this unchecked, the policy will use as many streams as the STU allows.
    4. Make sure the STU you choose to write to tape has max concurrency set appropriately (this is automatically set to the number of drives discovered, but you can clone to the STU and adjust as you need) - it needs to be set to at least 2 for your case.
    5. In the STU you could also enable multiplexing which will allow both multiple streams to write to one drive and other streams to write to a second drive (so with multiplexing of 2, 2 streams will write to one drive at the same time - this can give better drive utilisation/less shoe shining at the expense of slower restores - I think there is be a section in the Admin Guide vol 1 which describes this trade off

    Different combinations of 3, 4 and 5 can be used as you need to get optimal performance - try some combinations and see what works best for you. If you enable multiplexing, then you may need to change the job per policy value (if set) to allow the required number of streams to write to the two drives.

    Cheers