EIGRPv6
As with RIPng, EIGRPv6 works much the same as its IPv4 predecessor does (see Table
10.4)—most of the features that EIGRP provided before EIGRPv6 will still be available.
EIGRPv6 is still an advanced distance-vector protocol that has some link-state features.
The neighbor discovery process using hellos still happens, and it still provides reliable communication
with reliable transport protocol that gives you loop-free fast convergence using the
Diffusing Update Algorithm (DUAL).
Hello packets and updates are sent using multicast transmission, and as with RIPng,
EIGRPv6’s multicast address stayed almost the same. In IPv4 it was 224.0.0.10; in IPv6, it’s
FF02::A (A = 10 in hexadecimal notation).
But obviously, there are differences between the two versions. Most notably, and just as
with RIPng, the use of the network command is gone, and the network and interface to be
advertised must be enabled from interface configuration mode. But you still have to use the
router configuration mode to enable the routing protocol in EIGRPv6 because the routing process
must be turned on like an interface with the no shutdown command—interesting!
TABLE 1 0 . 4 IPv6 EIGRP Commands
Command Meaning
(config)#ipv6 router eigrp AS Enables EIGRP on the router
(config-rtr)#no shutdown Is required for EIGRP to be enabled on the router
(config-if)#ipv6 eigrp 10 Enables EIGRP on each interface you want to use
The configuration for EIGRPv6 is going to look like this:
Router1(config)#ipv6 router eigrp 10
The 10 in this case is still the autonomous system (AS) number. The prompt changes to
(config-rtr), and from here you must perform a no shutdown:
Router1(config-rtr)#no shutdown
Other options also can be configured in this mode, such as redistribution.
So now, let’s go to the interface and enable IPv6:
Router1(config-if)#ipv6 eigrp 10
The 10 in the interface command again references the AS number that was enabled in the
configuration mode.
Last to check out in this group is what OSPF looks like in the IPv6 routing protocol.