A vSphere cluster is a configuration that manages the added hosts pooling the available resources. Once the cluster has been created, you can move the hosts to the cluster. When the hosts are added to the cluster, the cluster manages the available resources and allows you to enable the vSphere HA, vSphere DRS, and vSphere FT features that are only available with clusters. These features will be covered in Chapter 15, Availability and Disaster Recovery .

To create a cluster, proceed as follows:

1. From the vSphere Client, log in to the vCenter Server.
2. In the Hosts and Clusters view, right-click on the configured data center object and select the New Cluster option.

3. Enter the name of the cluster and select the features you want to enable. Click OK to create the cluster. To better understand the available features displayed in the wizard, the HA feature provides business continuity, while DRS is used to balance the workload across the hosts.

Enhanced vMotion Compatibility (EVC) is a feature that allows VMs to vMotion across hosts with different processors in the same cluster. The caveat is that all processors must be from the same vendor (Intel or AMD) since a mixed cluster is not supported. Pay attention when you install a new ESXi server in the same cluster.

To add hosts to the created cluster, the easiest way is to drag and drop the ESXi hosts into the cluster. Alternatively, you can right-click on the hosts, select the Move To option, select the target cluster, then click OK. You can also use scripts to automate the process of adding hosts to the cluster. If you are prompted about resource pool management, leave the default option and click Yes.