The %TUN-5-RECURDOWN: Tunnel0 temporarily disabled due to recursive routing error message means that the generic routing encapsulation (GRE) tunnel router has discovered a recursive routing problem. This condition is usually due to one of these causes: + A misconfiguration that causes the router to try to route to the tunnel destination address using the tunnel interface itself (recursive routing) + A temporary instability caused by route flapping elsewhere in the network Reference: https://www.cisco.com/c/en/us/support/docs/ip/enhan