vSphere Availability Design for the Management Domain
The vSphere HA configuration protects the virtual machines of the management components whose operation is critical for the operation of your VMware Cloud Foundation environment. You consider the varying and sometimes significant CPU or memory reservations for the management virtual machines and the requirements of vSAN.
You configure several vSphere HA features to provide high availability for the management components of the SDDC.
vSphere HA Feature | Description |
|---|---|
Host failure response | vSphere HA can respond to individual host failures by restarting virtual machines on other hosts within the cluster. |
Response for host isolation | If a host becomes isolated, vSphere HA can detect and shut down or restart virtual machines on available hosts. |
Admission control policy | Configure how the cluster determines available resources. In a smaller vSphere HA cluster, a larger proportion of the cluster resources are reserved to accommodate ESXi host failures according to the selected admission control policy. |
VM and Application Monitoring | If a virtual machine failure occurs, the VM and Application Monitoring service restarts that virtual machine. The service uses VMware Tools to evaluate whether a virtual machine in the cluster is running. |
Policy Name | Description |
|---|---|
Host failures the cluster tolerates | vSphere HA ensures that a specified number of ESXi hosts can fail and sufficient resources remain in the cluster to fail over all the virtual machines from those ESXi hosts. |
Percentage of cluster resources reserved | vSphere HA reserves a specified percentage of aggregated CPU and memory resources for failover. |
Specify Failover Hosts | If an ESXi host fails, vSphere HA attempts to restart its virtual machines on any of the specified failover ESXi hosts. If a restart is not possible, for example, the failover ESXi hosts have insufficient resources or have failed as well, then vSphere HA attempts to restart the virtual machines on other ESXi hosts in the cluster. |