In the previous post I explained some basic stuff about IPv6 and how to configure IPv6 addresses on Cisco’s interfaces. Following this subject, I want to explain now how you can configure unicast dynamic routing protocols for IPv6 networks. The same as IPv4, the v6 generation of IP addresses supports routing protocol like OSPF, RIP and EIGRP, just that their names has been adapted to the v6 generation meaning OSPFv3, RIPng and EIGRP for IPv6.
From the routing protocols above I chose for today OSPFv3, because it is quite easy to understand and, why not, it is one my preferred routing protocols. OSPFv2 and OSPFv3 share the same key concepts, so if you understand the version for IPv4 you will have no problems to understand the one for IPv6. However, you should understand the most significant differences as well:
— to enable OSPFv3, you will have to use interface subcommands compared with the “network” statement under “router ospf” process in OSPFv2
— if there are multiple IPv6 addresses configured on a OSPFv3 enabled interface, then OPSFv3 advertise all the related networks
— OSPFv3 router-id (RID) has to be set in order to enable the routing protocol; this can be set automatically like in the OSPFv2 or manually
— OSPFv3 uses IPv4 for RID; if no IPv4 address is present on the router to be used as RID, than the OSPFv3 process cannot choose it’s RID
— OSPFv3 does not provide natively authentication like OSPFv2 does; for OSPFv3, the IPv6 structure covers this with its internal support for AH and ESP.
That’s about enough for you to configure a basic OSPFv3 routing protocol. If you are interested in more details about OSPFv3, you can check OSPFv3 documentation by Jeff Doyle and Jennifer Carroll on NetworkWorld.com
If for some reasons the tutorial above is not available for you, please check this text file which present in text mode everything needed to enable OSPFv3 point-to-point network configuration between 2 Cisco devices.