DMVPN Phase 3 Basic Configuration

DMVPN supports three different versions called “phases”. In my first DMVPN lesson I explained the basics and  the DMVPN phase 2 configuration and DMVPN phase 1 configuration lessons explain how to configure the first two phases.

This time, I’ll show you how to configure DMVPN phase 3. We’ll use the following topology for this:


We have one hub router and two spoke routers.


The configuration of DMVPN phase 3 and 2 is very similar. Let’s start with the following DMVPN phase 2 configuration on all routers:

Hub(config)#interface Tunnel0
Hub(config-if)#ip address
Hub(config-if)#ip nhrp authentication DMVPN
Hub(config-if)#ip nhrp map multicast dynamic
Hub(config-if)#ip nhrp network-id 1
Hub(config-if)#tunnel source GigabitEthernet0/1
Hub(config-if)#tunnel mode gre multipoint
Spoke1(config)#interface Tunnel0
Spoke1(config-if)#ip address
Spoke1(config-if)#ip nhrp authentication DMVPN
Spoke1(config-if)#ip nhrp map
Spoke1(config-if)#ip nhrp map multicast
Spoke1(config-if)#ip nhrp network-id 1
Spoke1(config-if)#ip nhrp nhs
Spoke1(config-if)#tunnel source GigabitEthernet0/1
Spoke1(config-if)#tunnel mode gre multipoint
Spoke2(config)#interface Tunnel0
Spoke2(config-if)#ip address
Spoke2(config-if)#ip nhrp authentication DMVPN
Spoke2(config-if)#ip nhrp map
Spoke2(config-if)#ip nhrp map multicast
Spoke2(config-if)#ip nhrp network-id 1
Spoke2(config-if)#ip nhrp nhs
Spoke2(config-if)#tunnel source GigabitEthernet0/1
Spoke2(config-if)#tunnel mode gre multipoint

To migrate from DMVPN phase 2 to 3, we only need two commands…here’s the first command:

Hub(config)#interface tunnel 0
Hub(config-if)#ip nhrp redirect 

The NHRP redirect command on the hub will inform spoke routers that they can reach another spoke router directly. The second command is needed on the spoke routers:

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Forum Replies

  1. Hi !

    I didnt have “ip nhrp redirect” in my IOS (C3745-ADVENTERPRISEK9_SNA-M) ??? that´s the only one i got…



  2. Hello Rene,
    First, thanks for your great job! it’s really simple to understand

    I have a problem with the configuration of the phase 3 DMVPN in GNS3. Since i type the 'ip nhrp redirect’command, i have te following error message ‘% NHRP-WARNING: ‘ip nhrp redirect’ failed to initialise’
    Could you please tell me why? I use the 7200 ios version 15.2.

    Thanks for your reply

  3. Hi Renee!
    Great lesson as always

    I was just wondering what about the “ip nhrp server-only” what is the purpose of the command??


  4. Hello Boris

    All of these commands are being used in this lesson except for the last one:

    I’ll attempt to give you a brief summary of each, but you can also see them in action in the lesson too.

    • ip nhrp shortcut - This command allows the spoke routers to makes changes in the CEF entry when they receive a redirect message from the hub.
    • ip nhrp network-id - This command simply enables NHRP on the interface. All NHRP devices within the logical network must be configured w
    ... Continue reading in our forum

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