Configure the 6to4 Tunnel

Configuration Conditions

Before configuring the 6to4 tunnel, complete the following tasks:

Configure the IP address of the physical interface, making the neighboring nodes reachable at the network layer.
Create one tunnel interface, and configure the basic parameters (refer to the configuration manual of the tunnel interface).
Configure any unicast routing protocol, making the route at the two ends of the tunnel reachable.

Table 11-4 Configure the 6to4 tunnel

Step		Command	Description
Enter the global configuration mode		configure terminal	-
Enter the tunnel configuration mode		interface tunnel tunnel-number	-
Configure the tunnel interface address interface address	Configure IPv6 global unicast address or anycast address or the local address of the site or auto get address	ipv6 address { ipv6-address/prefix-length [ anycast \| eui-64 ] \| autoconfig }	Mandatory By default, do not configure the IPv6 address on the tunnel interface.
	Configure the local address of the IPv6 link	ipv6 address ipv6-address link-local	Optional By default, after enabling IPv6 on the interface, automatically generate the local address of the link.
Configure the tunnel interface mode as 6to4 tunnel		tunnel mode ipv6ip 6to4	Mandatory By default, the tunnel interface mode is GRE over IPv4.
Configure the source address or interface name of the tunnel interface		tunnel source { ip-address \| interface-name }	Mandatory By default, do not configure the source address or interface name on the tunnel interface.

It is not necessary to configure the destination address for the 6to4 tunnel. The destination address used during tunnel encapsulation is automatically got from the imbedded IPv4 address in the 6to4 tunnel IPv6 address.
If adopting the interface mode when configuring the tunnel source, the source address of the tunnel is the master address of the source interface.
The two ends of the tunnel should be configured as the same tunnel mode. Otherwise, transmitting via the tunnel fails.
On one device, you can only configure one 6to4 tunnel.