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NHS @ NHRP

Hub Router configure

HUB(config)#interface Tunnel1 
HUB(config-if)# ip address 10.10.10.1 255.255.255.0 
HUB(config-if)# tunnel source FastEthernet0/0 
HUB(config-if)# tunnel mode gre multipoint 
HUB(config-if)#ip nhrp map multicast dynamic
HUB(config-if)#ip nhrp authentication OutBox 
HUB(config-if)# ip nhrp network-id 100


SPOKE Router
interface Tunnel1
Spoke_01(config-if)# ip address 10.10.10.2 255.255.255.0
 
Spoke_01(config-if)#tunnel source FastEthernet0/0
Spoke_01(config-if)#tunnel mode gre multipoint 

Spoke_01(config-if)# ip nhrp authentication OutBox
Spoke_01(config-if)# ip nhrp network-id 100


Spoke_01(config-if)#ip nhrp map 10.10.10.1 203.81.1.2
*Apr  5 03:33:03.307: NHRP: Tunnel1: Cache add for target 10.10.10.1/32 next-hop 10.10.10.1
*Apr  5 03:33:03.311:            203.81.1.2
*Apr  5 03:33:03.331: NHRP: Inserted subblock node for cache: Target Inserted subblock node for cache: Target 10.10.10.1/32nhop 10.10.10.1
*Apr  5 03:33:03.335: NHRP: Converted internal static cache entry for 10.10.10.1/32 interface Tunnel1 to external


Spoke_01(config-if)#ip nhrp nhs 10.10.10.1

*Apr  5 03:34:23.247: NHRP: Setting 'used' flag on cache entry with nhop: 10.10.10.1
*Apr  5 03:34:23.251: NHRP: NHRP successfully mapped '10.10.10.1' to NBMA 203.81.1.2


After Spoke router add NHRP NHS config it send request to HUB router.

*Apr  5 04:15:54.963: NHRP: Setting 'used' flag on cache entry with nhop: 10.10.10.1
*Apr  5 04:15:54.967: NHRP: NHRP successfully mapped '10.10.10.1' to NBMA 203.81.1.2
*Apr  5 04:15:54.971: NHRP: Send Registration Request via Tunnel1 vrf 0, packet size: 106
*Apr  5 04:15:54.971:  src: 10.10.10.2, dst: 10.10.10.1
*Apr  5 04:15:54.971:  (F) afn: AF_IP(1), type: IP(800), hop: 255, ver: 1
*Apr  5 04:15:54.971:      shtl: 4(NSAP), sstl: 0(NSAP)
*Apr  5 04:15:54.971:      pktsz: 106 extoff: 52
*Apr  5 04:15:54.971:  (M) flags: "unique nat ", reqid: 1
*Apr  5 04:15:54.971:      src NBMA: 203.81.2.2
*Apr  5 04:15:54.971:      src protocol: 10.10.10.2, dst protocol: 10.10.10.1
*Apr  5 04:15:54.971:  (C-1) code: no error(0)
*Apr  5 04:15:54.971:        prefix: 32, mtu: 17916, hd_time: 7200
*Apr  5 04:15:54.971:        addr_len: 0(NSAP), subaddr_len: 0(NSAP), proto_len: 0, pref: 0
*Apr  5 04:15:55.063: NHRP: Receive Registration Reply via Tunnel1 vrf 0, packet size: 126
*Apr 
Spoke_01(config-if)#5 04:15:55.067:  (F) afn: AF_IP(1), type: IP(800), hop: 255, ver: 1
*Apr  5 04:15:55.067:      shtl: 4(NSAP), sstl: 0(NSAP)
*Apr  5 04:15:55.067:      pktsz: 126 extoff: 52
*Apr  5 04:15:55.071:  (M) flags: "unique nat ", reqid: 1
*Apr  5 04:15:55.071:      src NBMA: 203.81.2.2
*Apr  5 04:15:55.071:      src protocol: 10.10.10.2, dst protocol: 10.10.10.1
*Apr  5 04:15:55.075:  (C-1) code: no error(0)
*Apr  5 04:15:55.075:        prefix: 32, mtu: 17916, hd_time: 7200
*Apr  5 04:15:55.075:        addr_len: 0(NSAP), subaddr_len: 0(NSAP), proto_len: 0, pref: 0


HUB Router
HUB#
*Apr  5 04:15:54.807: NHRP: Receive Registration Request via Tunnel1 vrf 0, packet size: 106
*Apr  5 04:15:54.811:  (F) afn: AF_IP(1), type: IP(800), hop: 255, ver: 1
*Apr  5 04:15:54.815:      shtl: 4(NSAP), sstl: 0(NSAP)
*Apr  5 04:15:54.815:      pktsz: 106 extoff: 52
*Apr  5 04:15:54.815:  (M) flags: "unique nat ", reqid: 1
*Apr  5 04:15:54.815:      src NBMA: 203.81.2.2
*Apr  5 04:15:54.815:      src protocol: 10.10.10.2, dst protocol: 10.10.10.1
*Apr  5 04:15:54.815:  (C-1) code: no error(0)
*Apr  5 04:15:54.815:        prefix: 32, mtu: 17916, hd_time: 7200
*Apr  5 04:15:54.815:        addr_len: 0(NSAP), subaddr_len: 0(NSAP), proto_len: 0, pref: 0
*Apr  5 04:15:54.847: NHRP: Send Registration Reply via Tunnel1 vrf 0, packet size: 126
*Apr  5 04:15:54.847:  src: 10.10.10.1, dst: 10.10.10.2
*Apr  5 04:15:54.847:  (F) afn: AF_IP(1), type: IP(800), hop: 255, ver: 1
*Apr  5 04:15:54.847:      shtl: 4(NSAP), sstl: 0(NSAP)
*Apr  5 04:15:54.847:      pktsz: 126 extoff: 52
*Apr  5 04:15:54.847:  (M) flags: "unique nat ", reqid: 1
*Apr  5 04:15:54.847:      src NBMA: 203.81.2.2
*Apr  5 04:15:54.847:      src protocol: 10.10.10.2, dst protocol: 10.10.10.1
*Apr  5 04:15:54.847:  (C-1) code: no error(0)
*Apr
HUB#  5 04:15:54.847:        prefix: 32, mtu: 17916, hd_time: 7200
*Apr  5 04:15:54.847:        addr_len: 0(NSAP), subaddr_len: 0(NSAP), proto_len: 0, pref: 0

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