LTO6 Tape utilisation

theja

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PREDATAR Control23

Hello Team,

We are using IBM3576 and LTO6 tapes for taking the backup, but the tapes are converting it mountable as there utilised is less than 150 GB. i need to know why the tapes are not fully utilised...
Please let me know if any parameter need to be used to use the tape fully...
 
PREDATAR Control23

DRM in use?

If tapes status is set to mountable, then these are offsite copies. Is this what you are doing and seeing? You will get this every time you do "backup stgpool" command copying data from the primary pool to the copy pool

Tapes will be set to mountable once offsite data is written to it regardless of how much data has been written to it.

This is done to have your DRM tapes for offsite storage. I have tapes moved to offsite at 3% utilized.
 
PREDATAR Control23

Yes DRM is in Use..

Why tape utilization is very less and it is converted to mountable state.. which is causing us to use more tapes....
 
PREDATAR Control23

Do you use collocation in any of your storage pool? q stg f=d
 
PREDATAR Control23

This is working the way it is designed. If you are backing up online pool to offsite pools, when the copy is complete, the tapes should be sent to offsite EVEN if utilization is just 1%. These are your DR tapes.

The same is true for DB backups. DB backup tapes are sometimes just 1% utilized BUT these needs to be sent offsite for recovery as you cannot append DB backups.

Having said this, are you separating storage pools by category, i.e. Unix, Windows, SQL, Oracle, etc? If you are, then be ready to accept that you will really have low utilization rates. If you are not, check if collocate by group is set.

In my environments (yes, environments as I have gone through 30+ environments) I separate storage pools for faster backup and quick recovery. At times I even do collocate by node or group to get even faster restores. However, these setups are coupled with hefty tape drive environments from 16 and up.

I always say: "tape is cheap but the cost of going out of business is expensive".
 
PREDATAR Control23

thanks for the explaination moon-buddy
 
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