Hello all,
I am having trouble with a GRE tunnel between two buildings on my campus. Here is the background. I have a three buildings that I am concerned about right now. My primary building has a C4510 core switch and buildings 12 and 24 both have a stack of C3850s. Both buildings are running a Haivision multicast video system that needs to be tunneled back to my primary building that houses the video furnace. The original setup for both buildings was to use an ISR4300 and create a GRE tunnel back to the core. At some point prior to me starting my current role, the tunnel for B24 was rebuilt to connect the C3850 stack to the core and the ISR was removed entirely. That tunnel is still operational today.
B12 still has the original setup with the ISR to the core. I am attempting to rebuild the tunnel from the C3850 stack to the core, like B24 has, and remove the ISR entirely. This GRE tunnel is the ONLY function that this ISR performs.
I have attempted to "copy/paste" the config that exist on B24's stack but cannot get the tunnel protocol to come up. On the B12 stack, the tunnel shows an up/down state. I've gone over both configs line by line and can't find what I might be missing. I've attached copies of the show run, show ip int brief, and show int tunnel for both buildings and the core.
For B24, the tunnel that I'm referencing is Tunnel1 and for B12, the tunnel is Tunnel12. Tunnel0 is the one that currently runs through the ISR that I am trying to eliminate.
I'm hoping that it's just something dumb that I'm missing but I'm out of ideas at this point.
