Elastic DRS uses an algorithm to maintain an optimal number of provisioned hosts to keep cluster utilization high while maintaining desired CPU, memory, and storage performance.
Elastic DRS monitors the current demand on your SDDC and applies an algorithm to make recommendations to either scale-in or scale-out the cluster. A decision engine responds to a scale-out recommendation by provisioning a new host into the cluster. It responds to a scale-in recommendation by removing the least-utilized host from the cluster.
- Single host starter SDDCs
Special considerations apply to two-host SDDCs. Only the Default Storage Scale-Out policy is available for two-host SDDCs. EDRS cannot scale-in an SDDC to fewer than three hosts. Therefore, when a two-host SDDC is scaled-out to three hosts, it cannot be scaled back to two hosts.
When the Elastic DRS algorithm initiates a scale-out, all Organization users receive a notification in the VMC Console and through email.