different hdd size in EVA3000 disk group

[Davide Depaoli_3]

Hello,
I'll ned to know if there is any issue or performance problem if I put into the same disk group 72GB hdd and 146GB hdd

I know that is better to have same hdd size, but customer now has 72GB hdd and now wants to buy 146GB.

Thanks in advance
kind regards
Davide

[Luk Vandenbussche]

Hi,

There is no performance issue if you mix disks in an EVA3000 in the same diskgroup

[Ivan Ferreira · Accepted solution]

You won't have performance problems, but the eva reserves space for protection acording to the protection level:

single = 2 x size of the largest disk
double = 4 x size of the largest disk

So, if you add 146 GB disks to the same disk group, you must calculate that with protection single you will loose 292 GB.

If you add the disks into a new disk group you need at least 8 disks and you will loose the same space if protection is set to single on the new disk group.

[Davide Depaoli_3]

thanks