DMVPN Phase 2 Basic Configuration

This topic is to discuss the following lesson:

Thanks for the good explanation Rene. I am using Cisco 7200 with IOS version 12.4(24g) but show dmvpn command is not working. Other configuration commands to setup DMVPN worked.

R1#show dmvpn
         ^
% Invalid input detected at '^' marker.

R1#

Hello Abhishek

It seems that this command is not available in your IOS version. You can see from the following Cisco CLI reference, that the command was introduced in the T train of code and not in the mainline which is your IOS version.

Even so, this is simply a show command that conveniently displays the components of the topology. You can still obtain the same information with a variety of other show commands such as those indicated in the following Cisco document:


Note this document was published before the introduction of of the show dmvpn command.

I hope this has been helpful!

Laz

Hello Rene

Hope you doing great.

On show dmvpn output I see Attrb --> S for Spokes routers meaning that the NBMA peer Address is learned Statically.

Shouldn’t be Attrb --> S like the Hub router?

Thank you in advance!

Regards,
Victor

Hello Victor

When you use DMVPN with NHRP in the configuration found in the lesson, on each spoke you use the following command:

ip nhrp map <tunnel address> <hub NBMA address>

This creates a static peer address, and that’s why you see the “S” indicator on the spoke router. This is considered a statically configured NBMA peer address.

On the hub, however, you have no such configuration. The hub is configured to accept NHRP requests to dynamically add the addresses of the spokes. For this reason, on the Hub, you will see the “D” designation that these are dynamically learned addresses.

You can, however, configure static spoke addresses on the hub if you like, but this defeats the purpose of the simplicity of implementation and the scalability of DMVPN.

I hope this has been helpful!

Laz

I hope this has been helpful!