After an associate configured a DMVPN hub, you execute the following command on the hub router:
Which of the following statements is true of this output?
- The NMBA address was statically configured
- The NHRP information did not come from the NHS
- The mapping was created through an NHRP registration request
- The device at 10.1.1.2 is behind a NAT router
The mapping was created through an NHRP registration request, as indicated by the flag setting registered. Next Hop Resolution Protocol (NHRP) can be used in place of static IP address to NBMA address mappings to allow the spoke routers in an mGRE hub-and-spoke configuration to discover one another’s physical IP addresses.
When the output of the show nhrp detail command shows the registered flag listed, it means that the mapping was created dynamically and was learned through a registration request to the next hop server (NHS).
The mapping was not created statically. Had it been created statically, the Type field would not be listed as dynamic. It would say static.
The NHRP information DID come from the next hop server (NHS). That is indicated by the presence of the authoritative flag. The NHS is the next hop to the destination as indicated by the routing table.
The device at 10.1.1.2 is not necessarily behind a NAT router. The presence of the nat flag in the output indicates that the device at 10.1.1.2 supports the NHRP NAT extension type for supporting dynamic spoke-to-spoke tunnels to or from spokes behind a NAT router. This flag does not mean that the spoke (NHS client) is behind a NAT router.
Describe DMVPN (single hub)