When you create a virtualization client or a backup set, a default subclient is created automatically, and all containers and images from the configured Docker deployment are automatically included in the default subclient content. This setting ensures that all containers and images will be included in backup operations.
To prevent duplicate backups of containers and images, any containers and images that are included in a user-defined subclient are automatically excluded from the default subclient. (Duplicate backups still occur if a container or image is included in multiple user-defined subclients.)
In a Docker deployment, at least one subclient should be able to cover unprotected containers and images. If you disable this feature for all subclients, some containers and images 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 containers and images that are not included in any other subclient in the backup set will automatically be backed up by the default subclient.
To remove the default coverage, you can add other content and then delete the All unprotected VMs entry.
If you remove all entries from the Contents of subclient list, All unprotected VMs appears in the list again.