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SQL Server AGs on vSphere and PowerStore increase availability by adding additional database copies. Secondary database copies can reside on the same or a different storage/vSphere datastore, raw device mapping (RDM), or any storage supported by both vSphere and SQL Server.
Like FCI, when SQL Server AGs are implemented on vSphere, some SQL Server failover scenarios such as hardware upgrades or host resource contention can be avoided by leveraging vMotion or DRS. If AG instances use different storage, the instances should be storage vMotion compatible. The design should also account for storage size and IO activity for storage vMotion activities. For example, the goal of avoiding a storage vMotion is a valid reason to use the same shared datastore for all VMs in the SQL AG.
PowerStore Metro volume is the key feature that enables dual-site or stretch cluster scenarios. Metro volume provides synchronous replication between two PowerStore clusters for load balancing and failover. This second synchronized copy allows for dual site or stretch cluster architectures either in the same data center or campus or separate geographic location as supported by PowerStore Metro volume.
SQL Server AGs can leverage Metro volume to move a workload between sites or PowerStore clusters without a failover by leveraging vMotion. A VMFS datastore hosted on a Metro volume is active and synchronized on both PowerStore clusters. Synchronized storage allows for a compute vMotion only.
Note: Currently PowerStore Metro volume does not support WSFC shared volumes and cannot be used with SQL Server FCI.