Embodiments relate to setting up direct mapped routers located across independently managed compute and storage networks for enabling multiple modes of communication over the cross-coupled links between the networks. An aspect includes identifying a characteristic of a local entity based on a unique location identifier assigned to the local entity and learning a characteristic of a remote entity based on a location identifier received over a cross-coupled link between the local entity and the remote entity. A port on a local entity router is then correlated with the received location identifier of the remote entity. A route is then built in the direct mapped router table at a location pointed to by the location identifier of the remote entity. An optimistic failover route is established from a storage entity to a compute entity when a cross-coupled link between the storage entity and the compute entity is broken.