Let’s learn the DMVPN configuration and verification using the topology shown here.
Once you have the topology built, watch the videos I will be posting here that walk you through the configuration and verification of your hub and spokes.
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You can download this VIRL topology here:
https://drive.google.com/open?id=1U8hNA3J9eJcO5OYVhJD-8fWYz3OSfe2q