Rolling cluster upgrades
Rolling Cluster Upgrades is a new feature in Windows Server 2016 that enables you to upgrade the operating system of your cluster nodes from Windows Server 2012 R2 to Windows Server 2016, without the need to stop the underlying Hyper-V workloads or services.
There are a number of benefits to this approach. It does not require any additional hardware to upgrade, although you can add additional nodes temporarily to the cluster to provide some additional availability during the upgrade process. Failover clusters running Hyper-V virtual machine workloads can be upgraded from Windows Server 2012 R2 to Windows Server 2016, without incurring any downtime, that is, the cluster does not need to be stopped or restarted to perform the upgrade procedure.
A new cluster running in parallel is not required. The existing cluster is upgraded a node at a time in a round-robin fashion. In addition, existing cluster objects stored in Active Directory are leveraged. In fact, the upgrade...