During some Backup-/Failovertests we migrated some VMs from one HA Cluster to another.

After that we noticed that the vSphere HA Protection state from these VMs changed from “protected” to “unprotected”…

Doing some quick search we saw that this is a known issue… A workaround is to disable and re-enable HA on the destination cluster.

If you need more information take a look at VMware KB 2012682