There is not any way to get that particular functionality where the tunnel interface will go down when there is a link failure without upgradeing the router to a version of code that implements that feature. You might come close if you could run some type of oject tracking and track an address on the remote router. But I am not sure that the version of code that you are running supports that kind of object tracking. So you might need a code upgrade to do that one.
I run a lot of GRE tunnels and run EIGRP over the tunnels. I track the EIGRP neighbor status and that gives almost the same results as tracking the interface status. If the EIGRP neighbor on the tunnel goes down then there is a problem in the tunnel, and it is almost the same as directly detecting the failure in the tunnel.
We are pleased to announce availability of Beta software for 16.6.3. 16.6.3 will be the second rebuild on the 16.6 release train targeted towards Catalyst 9500/9400/9300/3850/3650 switching platforms. We are looking for early feedback from custome...