There are some configuration differences in Cisco IOS software when configuring OSPFv2 versus OSPFv3. However, it should be noted that these differences are not as significant as those between other versions of IPv4 routing protocols and their IPv6 counterparts.
In Cisco IOS software, OSPFv3 routing is enabled using the ipv6 router ospf [process ID] global configuration command. As is the case with OSPFv2, the OSPF process ID is locally significant to the router and does not need to be the same on adjacent routers in order for an adjacency to be established.
As is required for EIGRPv6 (which will be covered in the ICND2 section), the router ID for OSPFv3 must be either specified manually or configured as an operational interface with an IPv4 address (e.g., a Loopback interface). Similar to EIGRPv6, there are no network commands used when enabling OSPFv3. Instead, OSPFv3 is enabled on a per-interface basis and multiple instances may be enabled on the same interface.
Finally, when configuring OSPFv3 over NBMA networks, such as Frame Relay and ATM, the neighbour statements are specified under the specific interface using the ipv6 ospf neighbor [link local address] interface configuration command. In OSPFv2, these would be configured in Router Configuration mode.
NOTE: When configuring OSPFv3 over NBMA technologies, you should create static Frame Relay map statements using Link-Local addresses. This is because the Link-Local address is used to establish adjacencies, not the global Unicast address. For example, to create a static Frame Relay map statement and specify an OSPF neighbour for a Frame Relay implementation, the following configuration would be implemented on the router (we will cover Frame Relay in the ICND2 section):
| R1(config)#ipv6 unicast-routingR1(config)#ipv6 router ospf 1R1(config-rtr)#router-id 1.1.1.1
R1(config-rtr)#exit R1(config)#interface Serial0/0 R1(config-if)#frame-relay map ipv6 FE80::205:5EFF:FE6E:5C80 111 broadcast R1(config-if)#ipv6 ospf neighbor FE80::205:5EFF:FE6E:5C80 R1(config-if)#exit |