A traditional Nutanix cluster requires a minimum of three nodes, but Nutanix also offers the option of a two-node cluster for ROBO implementations and other situations that require a lower cost yet high resiliency option.
Unlike a one-node cluster, a two-node cluster can still provide many of the resiliency features of a three-node cluster. This is possible by adding an external Witness VM in a separate failure domain to the configuration. Nevertheless, there are some restrictions when employing a two-node cluster.
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