Configuring a tunnel

Configure a tunnel for IPv6 VLANs or brouter ports to communicate through an IPv4–only network. Create a point-to-point connection between the two isolated IPv6 devices by configuring the tunnel endpoints.

Do not create tunnels in a native IPv6 network.

Before you begin

  • The router or host at the source and destination of the tunnel must support both IPv4 and IPv6 protocol stacks.

About this task

Manual tunnels are point-to-point, so you configure both source and destination addresses. You must configure both IPv6 and IPv4 addresses for both source and destination devices. The IPv6 addresses must represent the same network, for example 6666::1/96 and 6666::2/96.

Tunnel interfaces are automatically configured with a link-local address in the format fe80::<local_ipv4_source_address>.

You cannot configure the maximum transmission unit (MTU) for tunnels. The default MTU value for tunnels is 1280.

Procedure

  1. Enter Global Configuration mode:

    enable

    configure terminal

  2. Create a tunnel:

    ipv6 tunnel <1-2000> source {A.B.C.D} address WORD<0-46> destination {A.B.C.D}

Example

Create tunnel 2:

Switch:1(config)#ipv6 tunnel 2 source 11.11.11.1 address 3000:0:0:0:0:0:0:1/64 destination 12.12.12.2

Variable definitions

Use the data in the following table to use the ipv6 tunnel command.

Variable

Value

<1-2000>

Configures the ID for the tunnel.

address WORD<0-46>

Assigns an IPv6 address and prefix to the tunnel.

destination {A.B.C.D}

Configures the address of the remote endpoint of the tunnel.

source {A.B.C.D}

Configures the address of the local endpoint of the tunnel.