About excluding virtual disks from the backup
NetBackup provides several methods to exclude virtual machine disks from backups. One method lets you exclude the virtual disks that are defined in a virtual machine's Custom Attributes. NetBackup then excludes those disks if you specify the custom attribute name in the backup policy.
Veritas provides a option in the NetBackup plug-in for vSphere Client (HTML5). You can use that option to configure and apply a custom attribute to a virtual machine or multiple virtual machines.
To use the plug-in to configure a custom attribute to exclude disks from backups, the vCenter Global credentials Manage custom attributes and Set custom attribute are required.