IOS GRE Tunnel配置
r4#show running-config interface tunnel 0
Building configuration...
Current configuration : 115 bytes
!
interface Tunnel0
ipaddress 14.0.0.2 255.255.255.252
tunnel source 10.0.4.9
tunnel destination 10.0.4.5
end
配置并不复杂，通过traceroute确认到达GRE Tunnel的对端IP地址仅经过一跳，即可以很容易确定GRE Tunnel已经被建立起来。。