You extend a configured cluster by adding hosts to it. With vSphere 6.7, you use the Cluster quickstart workflow in the vSphere Client.
After you have configured your cluster, you can scale it out by adding more hosts. Then, you specify the network configuration for the new hosts in the cluster. If during the initial configuration of the cluster you have postponed configuring the host networking, no configuration, as for the existing hosts, is applied to the newly added hosts.
