When you use MSCS in a vSphere High Availability (vSphere HA) or vSphere Distributed Resource Scheduler (DRS) environment, you must configure your hosts and virtual machines to use certain settings. All hosts that run MSCS virtual machines must be managed by a
vCenter Server system.
Enable vSphere HA and vSphere DRS in a Cluster (MSCS) in the vSphere Web Client All hosts that are running MSCS virtual machines can be part of a vCenter Server cluster with both vSphere HA and vSphere DRS enabled. You can enable vSphere HA and vSphere DRS in the Cluster Settings dialog box.
Create VM-VM Affinity Rules for MSCS Virtual Machines in the vSphere Web Client For MSCS virtual machines in a cluster, you must create VM-VM affinity or anti-affinity rules. VM-VM affinity rules specify which virtual machines should be kept together on the same host (for example, a cluster of MSCS virtual machines on one physical host). VM-VM anti-affinity rules specify which virtual machines should be kept apart on different physical hosts (for example, a cluster of MSCS virtual machines across physical hosts).
Enable Strict Enforcement of Affinity Rules (MSCS) in the vSphere Web Client To ensure that affinity and anti-affinity rules are strictly applied, set an advanced option for vSphere DRS. Setting the advanced option ForceAffinePoweron to 1 will enable strict enforcement of the affinity and anti-affinity rules that you created.
Set DRS Automation Level for MSCS Virtual Machines in the vSphere Web Client You must set the automation level of all virtual machines in an MSCS cluster to Partially Automated. When you set the vSphere DRS automation level for the virtual machine to Partially Automated, vCenter Server will perform initial placement of virtual machines when they are powered on and will provide migration recommendations for them.
Using vSphere DRS Groups and VM-Host Affinity Rules with MSCS Virtual Machines You can use the vSphere Web Client to set up two types of DRS groups: virtual machine DRS groups, which contain at least one virtual machine, and host DRS groups, which contain at least one host. A VM-Host affinity rule establishes an affinity (or anti-affinity) relationship between a virtual machine DRS group and a host DRS group.