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Grandmetric LLC
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EIN: 98-1615498
+1 302 691 94 10

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ul. Metalowa 5, 60-118 Poznań, Poland
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+48 61 271 04 43


Grandmetric LTD
Office 584b
182-184 High Street North
E6 2JA
+44 20 3321 5276

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  • DMVPN Phase 2 Single Hub – EIGRP – Hub example

    Design & Configure

    DMVPN Phase 2 Single Hub – EIGRP – Hub example

    Traffic Flow:

    • Packet is intended to be sent from Spoke1 to Spoke2 network
    • According to routing table Spoke’s2 network is known via its original next hop but it is marked in CEF as incomplete and next hop IP is marked simultaneously as CEF glean adjacency / punt (now, need to perform NHRP resolution) – the NBMA of next hop is unknown, so Spoke1 triggers NHRP resolution to NHS (including next hop of Spoke2, Source of its tunnel, it’s NBMA)
    • In the same time first packet is routed via Hub based on RIB
    • Similar thing is done by Spoke2 when it needs to send packet back to Spoke1
    • NHS responds with NHRP resolution and then CEF is populated as complete and Spokes can communicate directly

    DMVPN Phase 2 and EIGRP

    • Advertise spoke’s connected routes
    • Disable split horizon on hub (Spoke to Spoke prefix advertisement)
    • Disable Next hop self feature


    DMVPN Phase 2 EIGRP Hub EXample configuration



    R1 Hub:

    router eigrp 111
    interface Tunnel0
    ip address
    no ip redirects
    no ip next-hop-self eigrp 111
    ip nhrp authentication gmlabs
    ip nhrp map multicast dynamic
    ip nhrp network-id 111
    no ip split-horizon eigrp 111
    no ip split-horizon
    tunnel source Loopback0
    tunnel mode gre multipoint
    tunnel key 123
    tunnel protection ipsec profile DMVPN_PROFILE

    Author: Marcin Bialy