Cleanur wrote:
Step 1 is a little confusing.
You don't actually need to license DO in order to re-balance the array after adding new drives, nor should you need to create new CPG's to migrate volume to.
DO licensing allows you to tune individual volumes to new CPG's with differing properties e.g Disk Class, RPM, Raid Type, Stripe Size etc so it's a more granular data mobility tool than tunesys which is system wide.
Tunesys is basically a free subset of the above DO functionality which allows automated re-balancing of data across all drives in the array, however it lacks the above granularity of control that DO provides for individual volumes.
So whether or not you have DO licensing, you simply need to run Tunesys after adding new drives and you're done, no need to create new CPGs as the new drives will automatically be added to the existing CPG's (assuming you didn't set a custom filter).
Hope this makes sense.
Unless I am misunderstanding the explanations I was given and HP's own description of DO here,
http://www8.hp.com/us/en/products/stora ... b=features, DO is needed or at least beneficial to re-balancing existing chunklets on CPGs. Tunesys is part of this, but DO is needed to properly re-balance: "Drives large scale performance optimizations with one-button system rebalance after adding new resources to the system...".
When you add new disks to a system with existing CPGs, from all I've read and what HP senior techs explained to me, DO must be configured before adding them or existing CPGs will continue to write chunklets only to the original drives they were created with, even after tunesys. Without DO, the only way to mitigate this behavior is to create a new CPG which spans all disks and migrate vvols from the original CPGs to it. This info is straight from multiple engineers at HP as well as our HP solutions architect.