For example, for a balance of high read and write performance with high availability for database or similar transactional applications, RAID 1 (mirroring) or RAID 10 (RAID 1 with RAID 0-Stripe) on fast 10K or 15K Fibre Channel (FC) or SAS disk drives is a good option. For applications that need a good read performance, little write activity, and where there is a need to reduce costs, RAID 5 (stripe with rotating parity) is a good fit. For applications where there is a focus on having as much capacity as possible at the lowest cost, yet maintain availability using large capacity 1 TB or 2 TB SATA disk drives, RAID 6 (stripe with dual parity) or vendor specific variations are a good option. Of course, you can use a mix of RAID levels, because most storage systems today support multiple RAID levels. Overall, the key to finding the perfect RAID level for your SMB is finding that balance of performance, availability, capacity and economics to meet your particular application needs.
This was first published in September 2009