Configuring an IP tunnel

Prerequisites

A enabled layer 3 interface with an IP address assigned to it, created with the command interface.

Procedure
  1. Create a IP tunnel with the command interface tunnel.
  2. Set the IP address for the tunnel. For a GRE, tunnel use the command ip address. For an IPv6 in IPv4, use the command ipv6 address.
  3. Set the source IP address for the tunnel with the command source ip.
  4. Set the destination IP address for the tunnel with the command destination ip.
  5. Optionally, set the TTL (hop count) for the tunnel with the command ttl.
  6. Optionally, set the MTU for the tunnel with the command ip mtu.
  7. Optionally, add a description to the tunnel with the command description.
  8. By default, the tunnel is attached to the default VRF. Attach it to a different VRF with the command vrf attach.
  9. Enable the tunnel with the command no shutdown.
  10. Review tunnel settings with the command show interface tunnel.

Example

This example creates the following configuration:

  • Creates GRE tunnel 33.
  • Set the tunnel IP address to 10.10.20.209/24.
  • Sets the tunnel source IP address to 10.10.10.1.
  • Sets the tunnel destination IP address to 10.10.10.2.
  • Enables the tunnel. 
switch(config)# interface tunnel 33 mode gre ipv4
switch(config-gre-if)# ip address 10.10.20.209/24
switch(config-gre-if)# source ip address 10.10.10.1
switch(config-gre-if)# destination ip address 10.10.10.2
switch(config-gre-if)# no shutdown