During a reconfiguration of a Tunnel, I added an administrative distance of 111 to a static route. Our environment is OSPF. This AD caused the tunnel to flip-flop up and down and no GRE data was exchanged between sites. When the AD was removed, so was the problem and the Tunnel is up. Please explain why this did not work.
Possibly the route was more specific of anything ospf, did target tunnel destination over the tunnel itself, and this cause recursion and self-shutdown of the tunnel.