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Table Of Contents
Configuring vSphere HA Cluster Settings in the vSphere Client
When you create a vSphere HA cluster or configure an existing cluster, you must configure settings that
determine how the feature works.
In the vSphere Client, you can configure the following vSphere HA settings:
Host Monitoring
Enable host monitoring to allow hosts in the cluster to exchange network
heartbeats and to allow vSphere HA to take action when it detects failures.
NOTE Host Monitoring is required for the vSphere Fault Tolerance recovery
process to work properly.
Admission Control
Enable or disable admission control for the vSphere HA cluster and choose a
policy for how it is enforced.
Virtual Machine Options
Set the VM restart priority and host isolation response.
VM Monitoring
Enable VM Monitoring or VM and Application Monitoring.
Datastore Heartbeating
Specify preferences for the datastores that vSphere HA uses for datastore
heartbeating.
Configure Host Monitoring and Admission Control
After you create a cluster, Host Monitoring enables the vSphere HA master host to respond to host or
virtual machine failures and management network isolation. Admission control allows you to specify
whether virtual machines can be started if they violate availability constraints. The cluster reserves
resources to allow failover for all running virtual machines on the specified number of hosts.
The Host Monitoring and Admission Control page appears only if you enabled vSphere HA.
Prerequisites
Launch the vSphere Client and log in to a vCenter Server system.
Procedure
1 In the vSphere Client, display the cluster in the inventory.
2 Right-click the cluster and select Edit Settings.
3 In the left pane of the Cluster Settings dialog box, select vSphere HA.
4 (Optional) Select Enable Host Monitoring.
5 Select an Admission Control option.
n
Enable: Disallow VM power on operations that violate availability constraints.
Enabling admission control enforces availability constraints and preserves failover capacity. Any
operation on a virtual machine that decreases the unreserved resources in the cluster and violates
availability constraints is not permitted.
n
Disable: Allow VM power on operations that violate availability constraints.
vSphere Administration with the vSphere Client
386 VMware, Inc.