Hi everyone,
For background, we are a SMB with <50 users. All the users are on our Exchange server (Database currently approximately 100GB, WAY TOO LARGE, but I digress), and 25 of the users are on a SQL based database application.
I've bought a pair of Dell R510's and a MD3200 SAN, which will be direct-attached to the R510's via 6Gbps Fibrechannel. Both physical servers will have 4 connections to the SAN.
The SAN is 12 disks, all 300GB 15K drives.
Now, I know in terms of total IOPS that the MD3200 will handle my needs, but I want to optimize the creation of LUM(s) as best I can for performance, and quite frankly, I'm really just not sure.
I've thought about doing 3 4-disk RAID 10 LUMs, but that leaves me no hot spares. I could go 2 5-disk RAID 5's with a hot spare per RAID, or just one big giant RAID 5 LUM with a single hot spare.
All of this will be used in a v5 VMWare environment.
Thoughts, opinions? And my thanks in advance for your thoughts 
Kevin