I am in the process of sizing a MSA 2052 storage solution and looking into how Raid configuration is done right.
I have read 2-3 different conf. guides and keep getting "The-power-of-two-rule"
....... Since the maximum number of drives within a disk group is 16, for RAID 5, one can only get a total of 9 drives maximum to obey the power-of-two rule. Because after 8 the next power of two is 16, and we need 17 drives to satisfy the rule, which is not possible within a disk group. For RAID 6, it is 10.
Is it not recomended/posible to setup a Raid 6 with 12 disks and one extra as hot-spare? Then you have 10 data disks, 2 par. disks and 1 hot-spare?
I keep reading of Raid 5 and 6 as best configurations. What else is "normal" when using more than 10 disks in one raid?
Thanks