Implementing Cisco Enterprise Advanced Routing and Services (ENARSI) — Question 212

A customer requested a GRE tunnel through the provider network between two customer sites using loopback to hide internal networks. Which configuration on
R2 establishes the tunnel with R1?

Answer options

• A. R2(config)#interface Tunnel1 R2(config-if)#ip address 172.20.1.2 255.255.255.0 R2(config-if)#ip mtu 1400 R2(config-if)#ip tcp adjust-mss 1360 R2(config-if)#tunnel source 192.168.20.1 R2(config-if)#tunnel destination 192.168.10.1
• B. R2(config)#interface Tunnel1 R2(config-if#ip address 172.20.1.2 255.255.255.0 R2(config-if)#ip mtu 1400 R2(config-if)#ip tcp adjust-mss 1360 R2(config-if)#tunnel source 10.10.2.2 R2(config-if)#tunnel destination 10.10.1.1
• C. R2(config)#interface Tunnel1 R2(config-if)#ip address 172.20.1.2 255.255.255.0 R2(config-if)#ip mtu 1500 R2(config-if)#ip tcp adjust-mss 1360 R2(config-if)#tunnel source 10.10.2.2 R2(config-if)#tunnel destination 10.10.1.1
• D. R2(config)#interface Tunnel1 R2(config-if)#ip address 172.20.1.2 255.255.255.0 R2(config-if)#ip mtu 1500 R2(config-if)#ip tcp adjust-mss 1360 R2(config-if)#tunnel source 192.168.20.1 R2(config-if)#tunnel destination 10.10.1.1

Correct answer: B

Explanation

The correct answer is B because it specifies the correct tunnel source and destination IP addresses that match the requirements for establishing a GRE tunnel. Options A, C, and D have incorrect tunnel source or destination addresses, which would prevent the tunnel from being established successfully.