Architecting a vSphere Compute Platform : Planning for Server Failure : 8.1 vSphere High Availability : 8.1.9 Sample HA Cluster Configuration
   
8.1.9 Sample HA Cluster Configuration
A service provider’s VMware Cloud Provider Program platform typically configures all vSphere HA parameters consistently across all clusters in all data centers. This helps to limit variability and simplify operational management. The following table provides design guidance for service providers by addressing the standard settings and options configured for vSphere HA attributes.
Table 17. Sample vSphere HA Settings
Attribute
Configuration
Cluster Name
boston-dc-01-payload-003
Number of ESXi Hosts
24
Host Monitoring
Enabled
Admission Control Response
Prevent virtual machines from being powered on if they violate availability.
Admission Control Policy
Enabled: Percentage of resources reserved:
13% CPU
13% Memory
N+3 for 24 node cluster (based on 1 to 8 Ratio)
Default Virtual Machine Restart Priority
Medium (majority of VMs)
Modify if necessary at VM level for High (critical VMs) / Disabled (non-critical VMs)
Host Isolation Response*
Shut down or power off
Virtual Machine Monitoring
Disabled
Virtual Machine Monitoring Sensitivity
N/A
Heartbeat Datastores
Automatically select datastores accessible from the host (default)
* Host isolation response refers to the action that vSphere HA takes when the host becomes isolated. The best practice in a vSAN environment might differ from a traditional storage vSphere HA design, depending on the deployed configuration. For information about the specific vSAN host behavior during a host isolation event, see the vSAN Support Center at https://www.vmware.com/support/virtual-san.