Hi guys! it’s time for me to write about configuration of OSPF IPv6 routing in Cisco IOS.
I will use example addresses from my workplace for this tutorial.
This is really simple, first configure the IPv6 addresses on the interfaces.
Router1(config)# interface fastethernet 0/0
Router1(config-if)#ipv6 address 2001:1ad8::1/126
Router2(config)#int fa 0/0
Router2(config-if)#ipv6 address 2001:1ad8::2/126
This sets up two addresses in a network containing 4 addresses from ::0 to ::3.
Verify the IPv6 connectivity with ping:
Router2#ping ipv6 2001:1ad8::1
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 2001:1AD8::1, timeout is 2 seconds:
Success rate is 100 percent (5/5), round-trip min/avg/max = 8/10/20 ms
As you can see, we have ping from the other side, now we can do the OSPF part.
Set a nullroute to redistribute to IPv6 OSPF, and configure IPv6 OSPF routing on Router1:
Router1(config)#ipv6 route 2001:1ad8:500::/64 null 0
Router1(config)# interface fa 0/0
Router1(config-if)#ipv6 ospf 1 area 0
Router1(config-if)#ipv6 router ospf 1
This enables the interface Fastethernet 0/0 in the OSPF area 0, and redistributes static IPv6 routes (the static one setup by ipv6 route) into IPv6 OSPF.
Do the same thing on Router2, except for the static route and redistribution.
Router2(config)#int fastethernet 0/0
Router2(config-if)#ipv6 ospf 1 area 0
This enables Fastethernet 0/0 in the OSPF area 0.
Now verify the IPv6 OSPF router neighborship
Router2#show ipv6 ospf neighbor
Neighbor ID Pri State Dead Time Interface ID Interface
172.16.1.1 1 FULL/BDR 00:00:31 4 FastEthernet0/0
As you can see, the other router is the backup designated router and it has loaded to the FULL status, which means everything is up and running.
Check for the route
Router2#sh ipv6 route ospf | include ^O
OE2 2001:1AD8:500::/64 [110/20]
We are receiving a /64 network as an external OSPF route, everything now works as expected.