Network Kings


$999 $499 only For All Access Pass Today! USE PROMO CODE : LIMITED

d :
h :

Ospfv3 ipv4 configuration

OSPFv2 is designed for IPv4 networks. OSPFv3 is specifically developed for IPv6 networks and is built on top of the Internet Protocol version 6. OSPFv2 uses IPv4 unicast addressing to exchange routing information between routers. It relies on IPv4 addresses to identify network interfaces and establish OSPF adjacencies. OSPFv3, in contrast, uses IPv6 link-local addresses for neighbor discovery and communication. It also supports IPv6 unicast addressing for exchanging routing information. 


Another difference is the way OSPFv2 and OSPFv3 handle the Routing Information Base (RIB). OSPFv2 uses the Routing Information Base (RIB) to store and manage IPv4 routing information. It maintains separate RIBs for different address families, such as IPv4 unicast and multicast. OSPFv3, on the other hand, employs a single RIB that can handle both IPv6 unicast and multicast routing information. OSPFv3 supports some advanced authentication like IPsec. 


So basically, in the latest version of OSPF, we do not need to configure OSPFv2 for IPv4 and OSPFv3 for IPv6 separately. OSPFv3 can support IPv4 and IPv6 simultaneously. 

One thing to remember in the case of ospfv3 is that the Router-Id should always be an IPv4 Address. So generally, if do not configure Router-ID manually, the first priority is given to the Highest loopback IP, then the Highest physical IP but the IPv4 address is not present in a topology, OSPF configuration shows the following error 

OSPFv2 is configured on the subnet but OSPFv3 is always configured on the interface 

For example: – 

OSPFv2 looks like: – 


R1(config)#router ospf {PROCESS ID} 

R1(config-router)#network (IP ADDRESS} {WILDCARD MASK} {AREA} 


But OSPFv3 looks like this: – 


R1(config)#interface {INTERFACE NO.} 

R1(config-if)#ospfv3 {PROCESS ID} ipv4 {AREA} 


Let’s configure OSPFv3:

A diagram of a circle with two lines on it.

R1(config)#router ospfv3 1 

%OSPFv3: IPv6 routing not enabled          


# We need to enable IPV6 routing 


R1(config)#ipv6 unicast-routing  

R1(config)#interface fa1/0 

R1(config-if)#ospfv3 1 ipv4 area 0 

% OSPFv3: IPV6 is not enabled on this interface    


# Since OSPFv3 is configured on the interfaces, we need to enable it on the interface as well 


R1(config-if)#ipv6 enable 

R1(config-if)#ospfv3 1 ipv4 area 0 




R2(config)#ipv6 unicast-routing  

R2(config)#interface fa2/0 

R2(config-if)#ipv6 enable  

R2(config-if)#ospfv3 1 ipv4 area 0 



When both the interface is configured, OSPF adjacency is established 

Let us on check the results: – 



  • R1#show ospfv3 neighbor  


          OSPFv3 1 address-family ipv4 (router-id 


Neighbor ID     Pri    State                Dead Time   Interface ID    Interface        1      FULL/BDR        00:00:38       7                             FastEthernet1/0 

  • R1#show ospfv3 database  


         OSPFv3 1 address-family ipv4 (router-id 


Router Link States (Area 0) 


ADV Router          Age         Seq#                  Fragment ID Link count Bits          77            0x80000002     0           1           None          73           0x80000002      0           1           None 


Net Link States (Area 0) 


ADV Router        Age         Seq#        Link ID    Rtr count        77           0x80000001    3           2 


Link (Type-8) Link States (Area 0) 


ADV Router         Age         Seq#           Link ID      Interface         193          0x80000001       3            Fa1/0         78            0x80000001      7             Fa1/0 


Intra Area Prefix Link States (Area 0) 


ADV Router        Age         Seq#           Link ID    Ref-lstype  Ref-LSID         77           0x80000001          3072       0x2002      3 

R1#show ipv6 route ospf  

IPv6 Routing Table – default – 1 entries 

Codes: C – Connected, L – Local, S – Static, U – Per-user Static route 

       B – BGP, R – RIP, H – NHRP, I1 – ISIS L1 

       I2 – ISIS L2, IA – ISIS interarea, IS – ISIS summary, D – EIGRP 

       EX – EIGRP external, ND – ND Default, NDp – ND Prefix, DCE – Destination 

       NDr – Redirect, O – OSPF Intra, OI – OSPF Inter, OE1 – OSPF ext 1 

       OE2 – OSPF ext 2, ON1 – OSPF NSSA ext 1, ON2 – OSPF NSSA ext 2, l – LISP 

R1#show ip route  

Codes: L – local, C – connected, S – static, R – RIP, M – mobile, B – BGP 

       D – EIGRP, EX – EIGRP external, O – OSPF, IA – OSPF inter area  

       N1 – OSPF NSSA external type 1, N2 – OSPF NSSA external type 2 

       E1 – OSPF external type 1, E2 – OSPF external type 2 

       i – IS-IS, su – IS-IS summary, L1 – IS-IS level-1, L2 – IS-IS level-2 

       ia – IS-IS inter area, * – candidate default, U – per-user static route 

       o – ODR, P – periodic downloaded static route, H – NHRP, l – LISP 

       + – replicated route, % – next hop override 


Gateway of last resort is not set 
 is variably subnetted, 2 subnets, 2 masks 

C is directly connected, FastEthernet1/0 

L is directly connected, FastEthernet1/0 

Ospfv3 ipv4 configuration
conf t
hostname R1
ipv6 unicast-routing
router ospfv3 1
address-family ipv4

int e0/0
ospfv3 1 ipv4 area 0
conf t
hostname R2
ipv6 unicast-routing
router ospfv3 1
address-family ipv4

int e0/0
ospfv3 1 ipv4 area 0