In the case you need to or your network team needs to do some network maintenance on the switches which VMware HA uses to communicate with the other hosts or where the das.isolationaddress (default gateway) is configured/ It’s smart to disable the Host Monitoring feature of VMware HA. You can do this easily by hand via edit cluster – VMware HA and uncheck the Enable Host Monitoring feature. See screenshot below:
But what if you have to disable Host Monitoring on multiple VMware HA cluster? Well, if you like PowerCLI, you can use the following script to disable or enable the HA Host Monitoring feature:
param( $vCenter, $option ) if($vCenter -eq $null){ Write-Host "Please enter the name of the vCenter Server" -ForegroundColor Yellow exit } switch($option){ enabled {"The HA Host Monitoring feature will be enabled"} disabled {"The HA Host Monitoring feature will be disabled"} default {"the option value could not be determined." exit } } Connect-VIServer $vCenter $clspec = New-Object VMware.Vim.ClusterConfigSpecEx $clspec.dasConfig = New-Object VMware.Vim.ClusterDasConfigInfo $clspec.dasConfig.hostMonitoring = $option foreach($cluster in (Get-Cluster | sort Name)){ $clview = Get-Cluster $cluster | Get-View $clview.ReconfigureComputeResource_Task($clspec, $true) } Disconnect-VIServer -Confirm:$false
Just save the script to change-HAHostMonitoring.ps1 and run it like this to disable the HA Host Monitoring feature:
Change-HAHostMonitoring vcenter.domain.loc disabled
If you want to enable Host Monitoring, just change disabled to enabled:
Change-HAHostMonitoring vcenter.domain.loc enabled
Note: Please test the script mentioned in this blog post in a lab or test environment before you use the script in a production environment.