I have a hub and spoke WAN with all sites using a dual router MPLS/Inet DMVPN model with 4331 routers. Each remote site has a local internet connection and guest network with inet access through both wired and wireless. The routers provide local LAN routing and are directly connected to either an MPLS circuit or a DMVPN tunnel connected to the internet. The guest network is between Meraki LAN switching and the local firewall, there is no routing provided by local 4331 routers. Here's the basic diagram of the DMVPN design.
I would like to setup a guest network that can failover to a remotely connected internet connection utilizing the 4331 routers. I'm setting up a guest VRF in the routers, but I am curious the best method to provide failover to another internet circuit across the WAN. Can I dynamically failover the default gateway for guest network using EIGRP or static routes when local internet failure is detected?
Here is the current guest network design for remote offices. The proposed, simplified design is at right.
The proposed, simplified design is below.
