Configuration -2 :Looks fine to me. I don't know which Ontap version your filer is running but SVM-scope NDMP is what is recommended in the newer version.
In SVM-scope - If your backup application supports the CAB extension and a volume and the tape device share the same affinity, then the backup application can perform a local backup or restore operation, instead of a three-way backup or restore operation. According to config-2, all the volumes that are local to the Node where tape-drive is located will be backed up, this is what we want, so that the backup is local to the Node.
Please note, the path for a given backup job is defined by the (DMA/Backup Software) Data Management Application without user intervention, depending on volume and tape colocation.
With the CAB extension supported by the backup application, the NDMP server provides affinity information about volumes and tape devices. Using this affinity information, the backup application can perform a local backup instead of a three-way backup if a volume and tape device are located on the same node in a cluster.
This is an old TR, but lot of the information in it still holds good.
NDMP in Clustered Data ONTAP for Tape Backup Software Applications | TR-4376 | NetApp