we have just migrated for our old fibre SAN storage to an IBM v3700 storwize with 24 SAS 600GB disks.
This storage is connected directly to two IBM ESXi 5.5 servers each with two 6Gbps multipath SAS controllers.
Up until now, I have configured the storage that I have used into multiple RAID5 groups. Each group would be for a different server/purpose. Mainly the RAID groups would be OracleDB, Oracle archive, SQL Server and the rest (file server, mail, etc). The most critical applications are Oracle and SQL Server.
My first concern is safety and then performance for our applications. So I have decided to go with RAID6 + spare(s).
My main concern now is, since we are using ESXi, should I configure the entire storage into one single RAID, saving space, and create data store volumes from ESXi for each server, or is this not a good practice and it's better to create separate hardware RAID groups?