Hi,
Here is the VMware KB which provides a workaround to enable this option for VMs on ESXi hosts in HA enabled cluster.
VMware KB: The Virtual Machine Automatic Startup / Shutdown feature in ESXi hosts in a VSA cluster gets disabled
Last time (couple of years back) when I was researching about this issue, I found that the these settings are applicable only when the VM remains on the same ESXi host and once its migrated to another ESXi host the automatic startup option for that VM is lost and needs to be reconfigured again. I am not sure if this behavior has changed with the newer versions of vSphere.
Hope this helps.
-Arun
Twitter: https://twitter.com/arunpande
Blog: http://highoncloud.blogspot.in/
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