GRE ××× 实现分支通过总部互访
1、把分支联通总部！
2、通过路由协议学习到分支的路由（isis ospf rip）！
3、看总部是否联通到分支，分支是否学习到分支的路由！
总部配置AR1
interface GigabitEthernet0/0/0
ip address 12.12.12.1 255.255.255.0
interface GigabitEthernet0/0/1
ip address 13.13.13.1 255.255.255.0
interface NULL0
interface LoopBack0
ip address 1.1.1.1 255.255.255.0
interface Tunnel0/0/0
ip address 192.168.1.1 255.255.255.0
tunnel-protocol gre
source 12.12.12.1
destination 12.12.12.2
interface Tunnel0/0/1
ip address 192.168.2.1 255.255.255.0
tunnel-protocol gre
source 13.13.13.1
destination 13.13.13.3
ospf 1
area 0.0.0.0
network 1.1.1.0 0.0.0.255
network 192.168.0.0 0.0.255.255
ip route-static 2.2.2.0 255.255.255.0 Tunnel0/0/0
ip route-static 3.3.3.0 255.255.255.0 Tunnel0/0/1
user-interface con 0
authentication-mode password
user-interface vty 0 4
user-interface vty 16 20
wlan ac
return
<1>
分支2 AR2
interface GigabitEthernet0/0/0
ip address 12.12.12.2 255.255.255.0
#
interface GigabitEthernet0/0/1
#
interface NULL0
#
interface LoopBack0
ip address 2.2.2.2 255.255.255.0
#
interface Tunnel0/0/0
ip address 192.168.1.2 255.255.255.0
tunnel-protocol gre
source 12.12.12.2
destination 12.12.12.1
#
ospf 1
area 0.0.0.0
network 2.2.2.0 0.0.0.255
network 192.168.0.0 0.0.255.255
#
ip route-static 1.1.1.0 255.255.255.0 Tunnel0/0/0
#
user-interface con 0
authentication-mode password
user-interface vty 0 4
user-interface vty 16 20
#
wlan ac
return
<2>
分支3 AR3
interface GigabitEthernet0/0/1
ip address 13.13.13.3 255.255.255.0
#
interface NULL0
#
interface LoopBack0
ip address 3.3.3.3 255.255.255.0
#
interface Tunnel0/0/1
ip address 192.168.2.2 255.255.255.0
tunnel-protocol gre
source 13.13.13.3
destination 13.13.13.1
#
ospf 1
area 0.0.0.0
network 3.3.3.0 0.0.0.255
network 192.168.0.0 0.0.255.255
#
ip route-static 1.1.1.0 255.255.255.0 Tunnel0/0/1
#
user-interface con 0
authentication-mode password
user-interface vty 0 4
user-interface vty 16 20
#
wlan ac
return
<3>
test AR2 AR3 互访
