I was recently involved in a conversations with regards to Virtual SAN and virtual machine migration capabilities. A few customers have been wondering about whether or not all of the vSphere migration operation and functions work with Virtual SAN due to the way the system works. One particular migration operation in question was around the ability to migrate virtual machines.
From a storage solution perspective, Virtual SAN delivers a distributed shared datastore that is presented to all members of a vSphere cluster. The Virtual SAN datastores are ONLY presented to the hosts that are members of a particular cluster. The fact that Virtual SAN datastore is shared amongst all the hosts in the cluster, it should be clear that virtual machine migration operations between hosts are possible. Apparently what didn’t seem to be clear was whether a vSphere Admins could migrate virtual machines across Virtual SAN clusters. In scenarios where there are multiple Virtual SAN clusters exist, and they are managed by the same vCenter Server, migrations of virtual machines between Virtual SAN clusters are possible even if the clusters can't see or access each others datastores. Virtual SAN’s deep integration with vSphere features allows vSphere Admins to migrate virtual machines between Virtual SAN enabled clusters by leveraging XvMotion. XvMotion is a vSphere feature that provides the ability to migrate virtual machines files across hosts or clusters over the network without the need of shared storage.
The demonstration below showcases the migration of virtual machines from a Virtual SAN enabled cluster named “VSAN Cluster Dev” onto a cluster named “VSAN Cluster Test”. This validates and should provide the answer to the questions around this topic.