2.在R1和R3上配置NAT,实现R4和R5连通ISP。
R1:
conf t
ip route 0.0.0.0 0.0.0.0 12.1.1.2
in f0/1
ip nat outside
in f0/0
ip nat inside
exi
access-list 1 permit ip any any
ip nat inside source list 1 interface f0/1 overload
R3:
conf t
ip route 0.0.0.0 0.0.0.0 23.1.1.2
in f0/0
ip nat outside
in f0/1
ip nat inside
exi
access-list 1 permit ip any any
ip nat inside source list 1 interface f0/0 overload
3.在R1和R3之间建立GRE VPN通道,使R4能够ping通R5
R1:
conf t
interface tunnel 1
tunnel source interface f0/1
tunnel destination 23.1.1.3
ip add 192.168.13.1
ip route 192.168.2.0 255.255.255.0 192.168.13.3
R3:
conf t
interface tunnel 1
tunnel source interface f0/0
tunnel destination 12.1.1.1
ip add 192.168.13.3