Exchange 2010 Changes Storage Demands: Page 2 of 2

This and the fact that the cost of storage capacity was falling fast while the cost of IOPS have been pretty constant, the folks at Microsoft decided that reducing the number of IOPS an Exchange server uses to store an item was more important than the space savings from single instance storage. Where a thousand heavy users on an Exchange 2003 server may have needed six or eight 15K RPM spindles to provide enough IOPS, that same thousand heavy users can happily run on six 7200RPM drives with Exchange 2010.

With the new Database Availability Groups, admins can create up to sixteen copies of each Exchange database. In the event of failure, another member of a cluster can start servicing the users in seconds, since it already has a copy of the database. Servers exchange log files to keep the various databases updated but still use Microsoft server clustering to handle failover.

Microsoft's pitching the combination of clustering and Database Availability Groups as not needing expensive SAN storage since Exchange no longer needs high performance or shared access to the LUN.  Many organizations will continue to use shared storage for Exchange to take advantage of snapshots or to maintain a single disaster recovery replication scheme, but Microsoft will use lower cost DAS in their total cost of ownership calculations for Exchange.

Another interesting option is using storage devices that replace single instance storage with data deduplication.  NetApp claims Exchange users can see 30% storage reductions with their basic deduplicaiton. I'm hoping to get a GreenBytes array or Exar/HiFn BitWackr into the lab and see just how well Exchange 2010 and data dedupe get along.