VNX 5100- Pool expansion with different size disks

Hi, I would not expand the pool with the drives you have, the size difference will make the pool very unbalanced.

Do you have a target RAID level you are trying to create (even though the recommended for NL-SAS is R6) ?

Regardless of whether you use RAID 1/0 or recommended RAID 6, you are going to end up with a non-preferred drive count.

RAID 6 preferred drive count is multiples of 6+2 or 14+2

RAID 1/0 preferred drive count is multiples of  4+4

RAID 5 preferred drive count is multiples of 4+1 or 8+1

Don't forget a hot-spare either.

Have a look through the linked best-practices guide, and come back with any questions or new info, and we can advise further

https://support.emc.com/docu51389_White-Paper:-VNX-Unified-Best-Practices-for-Performance-VNX-OE-for-Block-5.32-and-File…

Hi,

I am going to configure the new disks in RAID 1 /0

Thanks for your answer.

Sent from Samsung Mobile.

FYI - NL-SAS drives will have lower performance then SAS drives. Also, a bit lower reliability - which is why for NL-SAS drives EMC recommends using R6.

Also when you expand a pool by adding more drives, you should always add the same number that you used to create the Pool. If you started out with 16 drives in the Pool, then you should add additional drives in groups of 16. If you add 15, it will create internal (private) raid groups in the Pool with different number of disks and potentially change the performance of the pool.

The Best Practice guide that Brett@S attached is a good place to start for an understanding of the best practices for Pools on the VNX.

glen