WFSC Limitations

• WSFC clustering supports the concept of including SQL Failover Cluster Instances (FCIs) in AlwaysOn availability groups. A FCI instance is analogous to the traditional Windows cluster SQL service, where nodes in the cluster share a storage pool. The WSFC allows for a mix of FCI and standalone SQL nodes and also allows these instances to span network subnets. Considerable complexity is available for multi-site resiliency. DPX AlwaysOn support does not currently include WSFC clusters containing FCI SQL instances.

• A WFSC cluster deployment might include hosting SQL database and transaction log data on CIFS/SMB shares to help improve data management and resilience. Note that Block backup can only snapshot and back up data hosted on physical devices; any data hosted on CIFS/SMB shares causes the backup to fail.