Datasheet

Lab – Configuring a Point-to-Point GRE VPN Tunnel
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Step 7: Save your running configuration.
Part 2: Configure a GRE Tunnel
In Part 2, you will configure a GRE tunnel between the WEST and EAST routers.
Step 1: Configure the GRE tunnel interface.
a. Configure the tunnel interface on the WEST router. Use S0/0/0 on WEST as the tunnel source interface
and 10.2.2.1 as the tunnel destination on the EAST router.
WEST(config)# interface tunnel 0
WEST(config-if)# ip address 172.16.12.1 255.255.255.252
WEST(config-if)# tunnel source s0/0/0
WEST(config-if)# tunnel destination 10.2.2.1
b. Configure the tunnel interface on the EAST router. Use S0/0/1 on EAST as the tunnel source interface
and 10.1.1.1 as the tunnel destination on the WEST router.
EAST(config)# interface tunnel 0
EAST(config-if)# ip address 172.16.12.2 255.255.255.252
EAST(config-if)# tunnel source 10.2.2.1
EAST(config-if)# tunnel destination 10.1.1.1
Note: For the tunnel source command, either the interface name or the IP address can be used as the
source.
Step 2: Verify that the GRE tunnel is functional.
a. Verify the status of the tunnel interface on the WEST and EAST routers.
WEST# show ip interface brief
Interface IP-Address OK? Method Status Protocol
Embedded-Service-Engine0/0 unassigned YES unset administratively down down
GigabitEthernet0/0 unassigned YES unset administratively down down
GigabitEthernet0/1 172.16.1.1 YES manual up up
Serial0/0/0 10.1.1.1 YES manual up up
Serial0/0/1 unassigned YES unset administratively down down
Tunnel0 172.16.12.1 YES manual up up
EAST# show ip interface brief
Interface IP-Address OK? Method Status Protocol
Embedded-Service-Engine0/0 unassigned YES unset administratively down down
GigabitEthernet0/0 unassigned YES unset administratively down down
GigabitEthernet0/1 172.16.2.1 YES manual up up
Serial0/0/0 unassigned YES unset administratively down down
Serial0/0/1 10.2.2.1 YES manual up up
Tunnel0 172.16.12.2 YES manual up up
b. Issue the show interfaces tunnel 0 command to verify the tunneling protocol, tunnel source, and tunnel
destination used in this tunnel.
What is the tunneling protocol used? What are the tunnel source and destination IP addresses associated
with GRE tunnel on each router?
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