Windows Server 2016 will bring some improvements on the Failover Clustering feature, meant to make your VMs be more resilient to cluster communication failures, such as a node disconnected or the cluster service crashed on a node.
This new feature makes the cluster more tolerant to transient network errors and in case of a heartbeat timeout, the host will go into isolation. This will allow the VMs on that host to continue working but it will prevent other VMs being placed on that host. You will see that the VMs on the isolated host will have the status unmonitored and depending on the type of storage, they can run in the Online state if using File Storage (SMB3/SOFS) or in the Paused Critical state if your are using Block Storage (FC/FCoE/iSCSI/SAS) because the node no longer has access to the Cluster Shared Volumes in the cluster. If the host becomes responsive within a certain period of time it will come out from isolation, otherwise the VMs will be failed over to other hosts.
When a node leaves the cluster 3 times within an hour or is determined to be flapping it will be quarantined and the VMs will be drained.
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