Backup nodes of a cluster

Hello, 

I explain the context and needs. 

I currently work in an environment where resources are stored in a cluster and the nodes of the cluster are not backed up. 

- I would like to save only the nodes in the cluster (local drive, local state disk system) 
   Excluding the resources already saved this cluster. 

Environment: Netbackup 7.5 ; OS windows server 2008 

Thank you for your help.