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Exam 300-101 Question id=424 VPN Technologies

Refer to the following output:
Router#show ip nhrp detail 10.1.1.2/8 via 10.2.1.2, Tunnel1 created 00:00:12, expire 01:59:47 TypE. Dynamic, Flags: authoritative unique nat registered used NBMA address: 10.12.1.2
What does the authoritative flag mean in regards to the NHRP information?

A. It was obtained directly from the next-hop server.
B. Data packets are process switches for this mapping entry.
C. NHRP mapping is for networks that are local to this router.
D. The mapping entry was created in response to an NHRP registration request.
E. The NHRP mapping entry cannot be overwritten.

Show NHRP: Examples
The following is sample output from the show ip nhrp command:
Router# show ip nhrp 10.0.0.2 255.255.255.255, tunnel 100 created 0:00:43 expire 1:59:16 Type: dynamic Flags: authoritative NBMA address: 10.1111.1111.1111.1111.1111.1111.1111.1111.1111.11 10.0.0.1 255.255.255.255, Tunnel0 created 0:10:03 expire 1:49:56 Type: static Flags: authoritative NBMA address: 10.1.1.2
The fields in the sample display are as follows:

  • The IP address and its network mask in the IP-to-NBMA address cache. The mask is always 255.255.255.255 because Cisco does not support aggregation of NBMA information through NHRP.
  • The interface type and number and how long ago it was created (hours:minutes:seconds).
  • The time in which the positive and negative authoritative NBMA address will expire (hours:minutes:seconds). This value is based on the ip nhrp holdtime command.
  • Type of interface:
    – dynamic — NBMA address was obtained from the NHRP Request packet.
    – static — NBMA address was statically configured.
  • Flags:
    – authoritative — Indicates that the NHRP information was obtained from the Next Hop Server or router that maintains the NBMA-to-IP address mapping for a particular destination.
Reference