Create a custom alarm. Choose "Cluster" in Alarm Type and try "DRS disabled" and "DRS enabled" triggers.
No Specific alarms are defined by default for this in vSphere. However you can create some custom alarms for this.
- Set Alarm type to Monitor 'Clusters'
- Create alarm for 'DRS Enabled'
- Create alarm for 'DRS Disabled'
You might also want to monitor cluster status, 'Cluster Status Changed' and 'Cluster Overcommited' event can be used for that.
Automation level can be set through powercli :
Set-Cluster Cluster -DRSEnabled $True -DRSAutomationLevel - FullyAutomated
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