yes, as stated, install the remote agent on both nodes,
the selection list is kinda complex.
for NODE SPECIFIC DRIVES (like OS etc, stuff that is not shared in the cluster) use the NODE NAME OR NODE IP ADDRESS
for clustered stuff, use the RESOURCE NAME for the resource group that has the physical disk with the data you want to back up./
so let me do an example.
you have 2 nodes, called ClusterNode1 and ClusterNode2, both with the OS and node specific programs on C:
you have 2 LUNs on your shared storage, the Quorum on Q: and the data disk Z:.
you have 2 resource groups. one with just the quorum (Q:), the cluster name "ClusterA" and IP. the second with the data disk (Z:), several services, and the virtual server name,"VServerA" and ip
your selection list should be:
\\ClusterNode1\C:
\\ClusterNode1\VolumeShadowState
\\ClusterNode2\c:
\\ClusterNode2\VolumeShadowState
\\ClusterA\Q:
\\VServerA\Z:
or similar.