Geographically dispersed (majority node set) server clusters are built on a networking and storage infrastructure with characteristics that are very different from a standard quorum device server cluster. Therefore, they are certified under a separate testing program. If you want to convert your existing server cluster to a geographically dispersed server cluster, work with your hardware vendor to obtain a geographically dispersed server cluster configuration that has been certified by Microsoft.
You can create many geographically distributed solutions by adding data-replication software and extended Local Area Network (LAN) hardware to existing certified configurations. However, these solutions radically change the nature of a precertified configuration, particularly with respect to timing and latency. Therefore, Microsoft requires that, for it to be supported by Microsoft, the hardware and software configuration of a geographically dispersed cluster be one that is certified and listed on the cluster Hardware Compatibility List (HCL).For additional information about the HCL and Windows Clustering, click the following article number to view the article in the Microsoft Knowledge Base:
You can create many geographically distributed solutions by adding data-replication software and extended Local Area Network (LAN) hardware to existing certified configurations. However, these solutions radically change the nature of a precertified configuration, particularly with respect to timing and latency. Therefore, Microsoft requires that, for it to be supported by Microsoft, the hardware and software configuration of a geographically dispersed cluster be one that is certified and listed on the cluster Hardware Compatibility List (HCL).For additional information about the HCL and Windows Clustering, click the following article number to view the article in the Microsoft Knowledge Base:
309395 The Microsoft support policy for server clusters, the Hardware Compatibility List, and the Windows Server Catalog
Nonqualified software solutions on existing signed hardware are not supported.