My new white paper on CCR and DAS is now available!!
Continuous Cluster Replication and Direct Attached Storage: High Availability Without Breaking the Bank can be found on 3Sharp's Notable Accomplishments page, or downloaded directly from the link I've provided. Here's a quick synopsis of the paper:
The days of 2GB drives, tiny user mailbox sizes, and limiting Exchange Server to run on a single database have long since passed; storage options now abound, and disk space is cheap. Over the past ten years, storage area networks (SANs) have become ubiquitous, and IT management has often been persuaded that all data should reside on the SAN. However, the idea that the SAN is the best option for Exchange Server storage needs to be revisited; there are other options available today that provide the necessary reliability at greatly reduced cost.
The choice of building Exchange Server 2007 as a 64-bit architecture, and the availability of massive, cheap RAM, leads to greatly-reduced input/output operations per second (IOPS) for disk access. The synchronicity between this fact, and the availability of cheap disk space allows organizations to rethink their approach to storage. In this whitepaper, we explain the benefits of using Direct Attached Storage (DAS) as opposed to a SAN for Exchange Server Cluster Continuous Replication (CCR). We argue the use of DAS for CCR clusters, and provide a counterpoint to the idea that a SAN is the best storage option for CCR deployments.