From the VM group content dialog box, you can create disk filters to exclude virtual machine disks from backups.
From the navigation pane, go to Protect > Virtualization.
The Virtual machines page appears.
On the Hypervisors tab, click the hypervisor.
The hypervisor page appears. The VM groups area displays summary information for any existing VM groups.
Click an existing VM group.
Under Content, click Manage.
The VM group content dialog box appears.
The Disk Filters tab shows disks to be excluded from backups.
On the Disk Filters tab, to remove a filter, click in the Actions column of the row for the filter and select Remove.
To exclude virtual machine disks, click Add disk filter.
In the Add disk filter dialog box, provide information for the rule:
From the Disk filter type list, choose one of the following:
Blob URI/pattern: In the Blob URI/pattern box, type the URI for an Azure blob or a pattern with wildcards to identify blob storage objects.
Disk name/pattern: In the Disk name/pattern box, enter the name of the disk or a pattern using the '*' wildcard to represent a string of characters (for example, disk12.vhd or disk*.vhd).
For Azure managed disks, enter the name of the disk or pattern without the file extension (for example, disk12 or disk*).
Disk tag: In the Name box, type the name of a tag or a pattern using the '*' wildcard to represent a string of characters (for example, name123 or name*). In the Value box, type a value for the tag or a pattern using the '*' wildcard to represent a string of characters (for example, value123 or value*). Both the Name and Value fields are used together to identify specific disks.
Disk type: To filter the operating system volume, select OS Disk (the only value).
To edit a rule, click in the Actions column of the row for the filter and select Edit rule.
Click OK to save the changes to VM group content.