I have a hard time to decide which option would be better for Hot Data Nodes sizing:
A) 12 x 10 TB 7.2k, single 12G Raid Controller
Pros: Total cost per GB would be less
Cons: Less number of data nodes, It takes more to replicate data in the case of node failure
B) 24 x 2 TB 7.2k, single 12G Raid Controller
Pros: Higher number of data nodes, It takes less to replicate data in the case of node failure
Cons: 1 single disk controller might create a bottleneck for 24 disks especially in the case of using single drive raid-0 to take advantage of Raid controller caching, total cost per GB would be higher
I was wondering how bad would be to use a data node with a 56x10TB disk with 2 Raid Controller for a cold storage?