This is GRE tunnel setup between two router. The public IP of router A is 1.1.1.1, public IP of router B is 2.2.2.2. Customer wants to connect two site through tunnel. All traffic from router B will first go to router A and then either access to internet or private network. Customer finds that after configuring router A and B, tunnel is down in state. Below is the configuration of router A and B.
Configuration of router A:
Int tunnel 0/0/1
Tunnel-protocol gre
Ip address 192.168.0.1 255.255.255.252
Source 1.1.1.1
Destination 2.2.2.2
Int vlan 1
Ip address 10.1.1.1 255.255.255.0
Ip route 0.0.0.0 0.0.0.0 1.1.1.100
Ip route 10.2.2.0 255.255.255.0 tunnel 0/0/1
Configuration of router B:
Int tunnel 0/0/1
Tunnel-protocol gre
Ip address 192.168.0.2 255.255.255.252
Source 2.2.2.2
Destination 1.1.1.1
Int vlan 1
Ip address 10.2.2.2. 255.255.255.0
Ip route 0.0.0.0 0.0.0.0 2.2.2.100
Ip route 0.0.0.0 0.0.0.0.0 tunnel 0/0/1
After checking the configuration, it was found that in router B, tunnel can’t find its destination end because it choose its own default route which results in recursive routing.<?xml:namespace prefix = "o" ns = "urn:schemas-microsoft-com:office:office" />
