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

In the navigation tree, expand the following folders: Configuration > IPv6.
Click Tunnel.
Click the Tunnel Config tab.
Click Insert.
Beside the LocalAddress field, click the button, and then select the IPv4 address for the local VLAN or brouter port.
In the RemoteAddress field, type the IPv4 address for the destination VLAN or brouter port.
In the ID field, type a number to represent the tunnel.
In the IPv6AddressAddr field, type the IPv6 address for the tunnel VLAN or brouter port.
In the IPv6AddressPrefixLength field, type the number of bits to advertise in the IPv6 address.
Click Insert.

Tunnel Config field descriptions

Use the data in the following table to use the Tunnel Config tab.


Name	Description
AddressType	Shows the address type over which the tunnel encapsulates packets.
LocalAddress	Configures the address of the local endpoint of the tunnel.
RemoteAddress	Configures the address of the remote endpoint of the tunnel.
EncapsMethod	Configures the tunnel mode, which is manual for manually configured tunnels.
ID	Configures the ID for the tunnel.
IfIndex	Shows the value of ifIndex that corresponds to the tunnel interface. A value of 0 indicates that the interface index has not yet been assigned. This field appears only on the Tunnel Config tab.
Ipv6AddressAddr	Specifies the IPv6 address for the local VLAN or brouter port. This field appears only on the Insert Tunnel Config dialog box.
Ipv6AddressPrefixLength	Specifies the number of bits to advertise in the IPv6 address. This field appears only on the Insert Tunnel Config dialog box.