Should cluster-aware applications developed for MSCS use a shared-disk or shared-nothing architecture for greatest scalability?
Microsoft recommends a shared-nothing architecture for cluster-aware applications because of its greater scalability potential. With shared-disk applications, copies of the application running on two or more servers in the cluster share concurrent read/write access to a single set of disk files, mediating ownership of the files using a “distributed lock manager” (DLM). A shared-nothing application, on the other hand, avoids the potential bottleneck of shared resources and a DLM by partitioning or replicating the data so that each server in the cluster works primarily with its own data and disk resources. In theory, MSCS can support either type of application. However, Microsoft has no plans at this time to include a DLM in the MSCS cluster services, so vendors would have to develop or license a DLM to implement a shared-disk application on MSCS. Microsoft has chosen to use the shared-nothing architecture for future versions of Microsoft BackOffice family applications because of that ar
