[Practice] GRE Tunneling

GRE Tunneling 실습

실습 코드

1. PC

PC1 : ip 10.10.10.10/24 10.10.10.254
PC2 : ip 10.10.20.20/24 10.10.20.254
PC3 : ip 172.16.10.40/24 172.16.10.254
PC4 : ip 192.168.10.30/24 192.168.10.254

2. R1

R1#conf t
R1(config)#int fa 0/0
R1(config-if)#ip addr 10.10.10.254 255.255.255.0
R1(config-if)#ip nat inside
R1(config-if)#no shutdown
R1(config-if)#int fa 1/0
R1(config-if)#ip addr 10.10.20.254 255.255.255.0
R1(config-if)#ip nat inside
R1(config-if)#no shutdown
R1(config-if)#int fa 0/1
R1(config-if)#ip addr 62.62.14.1 255.255.255.0
R1(config-if)#ip nat outside
R1(config-if)#no shutdown

R1(config-if)#access-list 1 permit 10.10.10.0 0.0.0.255
R1(config)#access-list 1 permit 10.10.20.0 0.0.0.255
R1(config)#ip nat inside source list 1 int fa 0/1 overload

R1(config)#ip route 0.0.0.0 0.0.0.0 62.62.14.4

R1(config)#int tunnel 0
R1(config-if)#tunnel mode gre ip
R1(config-if)#tunnel source fa 0/1
R1(config-if)#tunnel destination 62.62.56.6
R1(config-if)#ip address 192.168.1.1 255.255.255.0
R1(config-if)#ip route 172.16.10.0 255.255.255.0 192.168.1.2

3. R2

R2#conf t
R2(config)#int fa 0/0
R2(config-if)#ip addr 62.62.42.2 255.255.255.0
R2(config-if)#no shutdown
R2(config-if)#int fa 1/0
R2(config-if)#ip addr 62.62.27.2 255.255.255.0
R2(config-if)#no shutdown
R2(config-if)#int fa 0/1
R2(config-if)#ip addr 62.62.25.2 255.255.255.0
R2(config-if)#no shutdown

R2(config-if)#router rip
R2(config-router)#version 2
R2(config-router)#network 62.62.27.0
R2(config-router)#network 62.42.35.0
R2(config-router)#network 62.25.56.0
R2(config-router)#no auto-summary

4. R3

R3#conf t
R3(config)#int fa 0/0
R3(config-if)#ip addr 62.62.43.3 255.255.255.0
R3(config-if)#no shutdown
R3(config-if)#int fa 0/1
R3(config-if)#ip addr 62.62.35.3 255.255.255.0
R3(config-if)#no shutdown

R3(config-if)#router rip
R3(config-router)#version 2
R3(config-router)#network 62.62.43.0
R3(config-router)#network 62.62.35.0
R3(config-router)#no auto-summary

5. R4

R4#conf t
R4(config)#int fa 0/0
R4(config-if)#ip addr 62.62.14.4 255.255.255.0
R4(config-if)#no shutdown
R4(config-if)#int fa 1/0
R4(config-if)#ip addr 62.62.43.4 255.255.255.0
R4(config-if)#no shutdown
R4(config-if)#int fa 0/1
R4(config-if)#ip addr 62.62.42.4 255.255.255.0
R4(config-if)#no shutdown

R4(config-if)#router rip
R4(config-router)#version 2
R4(config-router)#network 62.62.14.0
R4(config-router)#network 62.62.42.0
R4(config-router)#network 62.62.43.0
R4(config-router)#no auto-summary

6. R5

R5#conf t
R5(config)#int fa 0/0
R5(config-if)#ip addr 62.62.25.5 255.255.255.0
R5(config-if)#no shutdown
R5(config-if)#int fa 1/0
R5(config-if)#ip addr 62.62.56.5 255.255.255.0
R5(config-if)#no shutdown
R5(config-if)#int fa 0/1
R5(config-if)#ip addr 62.62.35.5 255.255.255.0
R5(config-if)#no shutdown

R5(config-if)#router rip
R5(config-router)#version 2
R5(config-router)#network 62.62.25.0
R5(config-router)#network 62.62.35.0
R5(config-router)#network 62.62.56.0
R5(config-router)#no auto-summary

7. R6

R6#conf t
R6(config)#int fa 0/0
R6(config-if)#ip addr 62.62.56.6 255.255.255.0
R6(config-if)#ip nat outside
R6(config-if)#no shutdown
R6(config-if)#int fa 0/1
R6(config-if)#ip addr 172.16.10.254 255.255.255.0
R6(config-if)#ip nat inside
R6(config-if)#no shutdown

R6(config-if)#access-list 1 permit 172.16.10.0 0.0.0.255
R6(config)#ip nat inside source list 1 int fa 0/0 overload

R6(config)#ip route 0.0.0.0 0.0.0.0 62.62.56.5

R6(config)#int tunnel 0
R6(config-if)#tunnel mode gre ip
R6(config-if)#tunnel source fa 0/0
R6(config-if)#tunnel destination 62.62.14.1
R6(config-if)#ip address 192.168.1.2 255.255.255.0
R6(config-if)#ip route 10.10.10.0 255.255.255.0 192.168.1.1
R6(config)#ip route 10.10.20.0 255.255.255.0 192.168.1.1

8. R7

R7#conf t
R7(config)#int fa 0/0
R7(config-if)#ip addr 62.62.27.7 255.255.255.0
R7(config-if)#ip nat outside
R7(config-if)#no shutdown
R7(config-if)#int fa 0/1
R7(config-if)#ip addr 192.168.10.254 255.255.255.0
R7(config-if)#ip nat inside
R7(config-if)#no shutdown

R7(config-if)#access-list 1 permit 192.168.10.0 0.0.0.255
R7(config)#ip nat inside source list 1 int fa 0/0 overload

R7(config)#ip route 0.0.0.0 0.0.0.0 62.62.27.2

※ Tunneling 적용을 안할 시 PC끼리의 통신은 안됨
※ R2 - R5 Router가 존재하는 구간은 실제 인터넷 망이라고 가정