The ClusterInMaintenance scheduling policy was added to limit activity in a cluster during maintenance tasks. When set, no new VMs may be started, except highly available VMs. Highly available VMs are still restarted properly upon host failure and any VM can be migrated. Users can create new highly available VMs and start them manually.
Updated documents: https://access.redhat.com/documentation/en-us/red_hat_virtualization/4.1/html-single/administration_guide/#sect-Scheduling_Policies https://access.redhat.com/documentation/en-us/red_hat_virtualization/4.1/html-single/administration_guide/#sect-Explanation_of_Settings_and_Controls_in_the_New_Cluster_and_Edit_Cluster_Windows https://access.redhat.com/documentation/en-us/red_hat_virtualization/4.1/html-single/technical_reference/#Load_Balancing_Policy_Cluster_Maintenance 4.2 also updated