After you create a DRS cluster, you can customize it and use it to manage resources.
To customize your DRS cluster and the resources it contains you can configure affinity rules and you can add and remove hosts and virtual machines. When a cluster’s settings and resources have been defined, you should ensure that it is and remains a valid cluster. You can also use a valid DRS cluster to manage power resources and interoperate with vSphere HA.
Note: In this chapter, "Memory" can refer to physical RAM or Persistent Memory.