When you create a virtualization client or a backup set, a default subclient is created automatically, and all virtual machines from the cluster are included in the default subclient content. This setting ensures that all virtual machines are included in backup operations.
To prevent duplicate backups of virtual machines, any virtual machines that are included in a user-defined subclient are automatically excluded from the default subclient. Duplicate backups still occur if a virtual machine is included in multiple user-defined subclients.
In a Nutanix AHV instance, at least one subclient should be able to protect unprotected VMs. If you disable this feature for all subclients, some virtual machines in the cluster might not be backed up.
When the default subclient is created, the Contents of subclient list in the Content tab displays All unprotected VMs as the content Type. That entry indicates that all virtual machines from the cluster that are not included in any other subclient in the backup set are automatically backed up by the default subclient.
To remove the default coverage, you can delete the All unprotected VMs entry.
If you remove all entries from the Contents of subclient list, then All unprotected VMs appears in the list again.