DMVPN configuration

[Naveen L]

Introduction:

This document gives information about DMVPN with a configuration example.

What is DMVPN?

DMVPN stands for Dynamic Multipoint VPN and it is an effective solution for dynamic secure overlay networks. In short, DMVPN is combination of the following technologies:

• Multipoint GRE (mGRE)
• Next-Hop Resolution Protocol (NHRP)
• Dynamic Routing Protocol (EIGRP, RIP, OSPF, BGP)
• Dynamic IPsec encryption
• Cisco Express Forwarding (CEF)

Physical Connectivity:

HUB:

ROUTER 2

ROUTER 3

ROUTER 4

DMVPN Config:

Once you have physical connectivity you can add the DMVPN configuration.

HUB

ROUTER 2

ROUTER 3

ROUTER 4

IPSEC:

Next you will need to add IPSEC, this will ensure that traffic is not sent in clear text. This configuration will be added to each router except router 1.

Dynamic Routing

To enable dynamic routing i am using EIGRP add the following configuration to each routers except router 1.

Verification:

Dynamic Tunnels:

NHRP Tunnels:

[Giuseppe Larosa]

Hello @Naveen L ,

instead of screnshots texts showing configuration commands are more useful in documentation

Hope to help

Giuseppe

[Naveen L]

@Giuseppe Larosa Sure will try add the same thanks

[paul driver]

Hello
I see you are just showing phase 2 DMVPN overlay running eigrp, you can also have (OSPF/BGP -iBGP/eBGP) and phase1/3 running dynamic routing protocols.

plus you can also have various dmvpn topology's 
single hub/single cloud - as you have here
single hub/dual cloud
dual hub/single cloud
dual hub/dual cloud

Additionally i see you are using the "old" IOS way of applying spoke NHRP registration/mapping, in more recent ios you can use a single statement for this regards dynamic multicast.

Example:
NHC (spoke)
ip nhrp nhs 10.1.1.1 nbma 192.168.1.100 mutilcast

[Naveen L]

Thanks for you letting me know that