Yosemite Server Backup 10.0 and Above
Yosemite Server Backup is not aware of VMware Clusters. To ensure that a guest machine is backed up properly if it fails over from one host to another, you will need to select the Host in a specific manner outlined below. As long as both hosts are Implicitly Selected, it will automatically backup the guest machine if it fails over from one machine to another. This can be done either by backing up through vCenter or from each host individually.
If you Check the Host, it will select all objects beneath it. This is considered an Implicit selection. Meaning, it Implies you want to select all objects, including any new objects added. As objects are added to this location, in this case Guest VMs, it will be selected. You can uncheck individual child objects, but as long as the Host has a Check Mark through it, new child objects will automatically be selected.
If you browse down below the host and check a Child Object without checking the Parent, this is considered an Explicit selection. Meaning, you only want to select those specific objects. Any new Child Objects for the Host will not automatically be selected. Notice the check box is Grey instead of Checked, this is the visual indication of Implicit vs Explicit selections.
This is the same logic used throughout the selection process and not limited to just VMware.
Backing up via vCenter is no different, you will simply have another layer above the Hosts for the vCenter object.
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