Deleting CPG

[martinkerr]

Hi,

I have a RAID 6 CPG which I am never going to use, I also have a RAID 1 & 5 CPG which are nearly full.

Is it possible to delete the R6 CPG and reuse those disks in the R1 or R5 CPG? If so, how? Are there any gotchas?

Thanks

[Noss]

If you have never used the RAID 6 CPG or no Virtual Volumes using that CPG, you are not going to get any capacity/disks back by deleting the CPG.

A CPG is just a template/policy for how volumes are distributed across all available drives (available drives being what is configured in the CPG configuration)

[martinkerr]

Hi,

Thanks for your reply.

So I have 3.6TB available/allocated for that CPG, how can I reclaim that disk space and reuse it for R5 or R1?

Thanks

[Noss]

CPGs can provision space from the same drive types as other CPGs so you could be looking at the space available if you were to start creating volumes in that CPG. But that may be the same space available to your R1 CPG. Obviously it will be less available. Also, if you were to start using the R6 CPG then space available to the other CPGs decreases.

Use the showspace command against your CPGs. "Est Free" will tell you what you have available if you continued growing out of those CPGs.

# showspace -cpg CPGNAME

[martinkerr]

Understood, just checked and yep, I can see now.

I am due some new drives to be delivered soon anyway to up the capacity.

Know of any good documentation for adding drives etc? Also to extend an existing CPG?

Thanks

[Noss]

At a high level, once the drives are installed they will automatically be available to the CPG if they meet the requirement for that CPG. No requirement to extend a CPG. There are some caveats to that based on having enough licenses, firmware installed for the new drives.

There are also some guidelines to follow on how many and where to install drives. I would recommend speaking to an HPE partner or support who can advise.

Try this for adding drives

http://h20564.www2.hpe.com/hpsc/doc/pub ... -c04777546

Finally, (depending on your model. I think 8200 it happens automatically) after new drives are installed and initialized, you'll probably want to run a tunesys to rebalance existing data across current and new drives. Again, support can clarify this step.

[martinkerr]

Excellent, we have an 8200

Thanks very much for your help!

[Richard Siemers]

If you used the R6 CPG before, and (re)moved the volumes that were in it... it will hold on to some space in reserve. Try running a compact cpg to shrink it down.

[kk2491]

Also as Richard said you can give a dry run for compact CPG.

Command : compactcpg -dr <CPG_NAME>

This will show how much space will be released to free pool once compact CPG is completed.

Regards,
KK