I have a DMVPN hub with one wan connection/ISP. Our spokes are already connected on their primary wan connections (cable internet). We still have T1 lines at those locations and would like to use those lines as backups. What is the best way to configure these spoke routers for redundancy (keeping the DMVPN connection up in the process)? I've seen the usual tracking method, but that seems to be hit or miss. Also saw a recommendation to use loopback interfaces and just sort of blend the two wan connections together. Looking for any solutions that you have used that have worked well.
Thanks!
