CPG and Virtual Volume expansion

[maximallist]

Hey, everybody!
Help solve a problem on the 3PAR 8200:
1) additional disks (IDs 16-23) of 920GB have been added
2) existing disks 0-7 have 480GB capacity, 8-15 have 920GB capacity
3) there is CPG "R5_7plus1"
4) there is a Virtual Volume "datastore" which is exported to 3 ESXi hosts

Need to expand the "datastore" space to the maximum value after adding disks. As far as I understand, I need to expand the CPG "R5_7plus1" space first? How to do this?

[MammaGutt]

CPG will grow as required. No user interaction is required.

Keep in mind, that Vmware vCenter has _no_ knowledge about the 3PAR.

What you need to do, is expand the VV on the 3PAR (Action -> Edit). Then you need to extend it in Vmware.

Unless you want to create a new volume and storage vMotion some volumes to a new volume.

FWIW it is recommended to have multiple volumes (as they hold their own queues) to get optimal performance.

Also, it is recommended to use RAID6 and not RAID5 to avoid potential data loss with UREs.

[maximallist]

Hello, MammaGutt!
Thank you for such a detailed reply!

Do I understand correctly that:
1) It is not possible to change the RAID type from 5 to 6 for the existing CPG "R5_7plus1"?

2) The best option in the current scheme is to create a new additional CPG RAID6 and then create a new volume based on this CPG? If so, what value should I choose for the "Set size" parameter and how to correctly select the size of the new volume? (see screenshots).

Thank you in advance for your attention and understanding!

[MammaGutt]

You have three options.

1: Change setting on existing CPG and run tunesys.
2: Create new CPG with new settings and «tune» existing volume to new CPG (requires dynamic optimization license which most systems have)
3: Create new CPG with new settings and new volume and run storage vMotion of existing data.


1 is the easiest one. 2 will cleanup dedupe store, 3 will give you a clean datastore with the latest VMFS version available on your vsphere version.

2 and 3 also could require up to 50% free space when starting but would allow you to change other characteristics as well (enable/disable dedupe and/ot compression).