In general, the disclosure relates to a method for forwarding a packet through a multi-tier network by establishing a routing protocol session with network devices in the multi-tier network, obtaining routing protocol information from network devices of the multi-tier network, determining a group using the routing protocol information, generating an ordered group listing using network device identifiers (NDIs) for the network devices in the group, and programming a network device hardware of a network device of the set of network devices of the multi-tier network using the ordered group listing. The group includes a set of the network devices of the multi-tier network.