OSPFv3 in ipv4

[burhaans28]

Hi,

I am doing OSPFv3 in IPv4 Network, for my topology i have area 3 connected with area 2, i want to run virtual link between area3

to area 0,

pls help me how can i do that

[M02@rt37 · Accepted solution]

Hello @burhaans28,

Please find here example:

https://www.cisco.com/c/en/us/support/docs/ip/open-shortest-path-first-ospf/113204-ospfv3-vlink-config.html

[burhaans28]

Thanks for your reply,

As i am using only ipv4, the router is not accepting 

ipv6 router ospf 10
 router-id 2.2.2.2
 log-adjacency-changes
 area 23 virtual-link 3.3.3.3
this command

[David Ruess · Accepted solution]

I believe its the transit are that needs to be configured in the VL command. YOu put Area 23 and you dont have an Area 23 in yoor topology. The virtual link is not an Area as you have labeled in your diagram either. YOu need config on both ABRs pointing to each otherers Router-IDs. Try:

area 2 virtual-link 3.3.3.3

And configure the VL on the other side pointing to the other Router-ID as well.

-David

[burhaans28]

I tried but after area 2 I am not getting "virtual Link " option

[David Ruess · Accepted solution]

Since OSPFv3 uses address families and used IPv6 for transport you might have to configure it under the address-family

router ospfv3 1

address-family ipv6 unicast

area # virtual-link ????

See if you have a command set under that. You may also need to use a global IPv6 address to be reachable as the neighbors use link local for trasport.

-David

[burhaans28]

yeah it take the command, i also used global ipv6 address but still the virtual link is not up,

maybe virtual is not supported for ipv4 in ospfv3 

[David Ruess · Accepted solution]

After I was able to lab and do some research I don't believe VL are supported in IPv4 for OSPFv3. The only thing that I can see is that OSPFv3 used IPv6 for transport so it may not be able to handle an IPv4 VL. Your only option is to run OSPfV2 for IPv4 VL and IPv6 or OSPFv3 for IPv6 VL. The only downside is OSPFv3 is NOT backwards compatible with OSPFv2 so you would have to decide how you want to run it. I will not this looks like a lab for practice and not based on a real design as Virtual-links are Band-Aids until you can figure out a solution to NOT run VL in your environment. But nonetheless I was able to get the VL up and working in the IPv6 address family as seen below:

Routers have X.X.X.X where X is their Router-ID. Area 2 is the Area Between R2 and R4

R4 config and output

R4#sh run | sec router ospf
router ospfv3 1
router-id 4.4.4.4
!
address-family ipv4 unicast
exit-address-family
!
address-family ipv6 unicast
area 2 virtual-link 2.2.2.2
exit-address-family
R4#

R4#sh ospfv3 virtual-links

OSPFv3 1 address-family ipv6 (router-id 4.4.4.4)

Virtual Link OSPFv3_VL0 to router 2.2.2.2 is up
Interface ID 10, IPv6 address 2001:ABCD:FEED::2 <- this is the global IPv6 address configured on the Lo0 address of R2 reachable from R4
Run as demand circuit
DoNotAge LSA allowed.
Transit area 2, via interface GigabitEthernet0/0, Cost of using 1
Transmit Delay is 1 sec, State POINT_TO_POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Adjacency State FULL (Hello suppressed)
Index 1/1/2, retransmission queue length 0, number of retransmission 0
First 0x0(0)/0x0(0)/0x0(0) Next 0x0(0)/0x0(0)/0x0(0)
Last retransmission scan length is 0, maximum is 0
Last retransmission scan time is 0 msec, maximum is 0 msec
R4#

#############################################################

R2 config and output

R2#sh run | sec router ospf
router ospfv3 1
router-id 2.2.2.2
!
address-family ipv4 unicast
exit-address-family
!
address-family ipv6 unicast
area 2 virtual-link 4.4.4.4
exit-address-family
R2#

R2#sh ospfv3 virtual-links

OSPFv3 1 address-family ipv6 (router-id 2.2.2.2)

Virtual Link OSPFv3_VL0 to router 4.4.4.4 is up
Interface ID 10, IPv6 address 2001:ABCD:FEED::4 <- this is the global IPv6 address configured on the Lo0 address of R4 reachable from R2
Run as demand circuit
DoNotAge LSA allowed.
Transit area 2, via interface GigabitEthernet0/1, Cost of using 1
Transmit Delay is 1 sec, State POINT_TO_POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Adjacency State FULL (Hello suppressed)
Index 1/3/4, retransmission queue length 0, number of retransmission 0
First 0x0(0)/0x0(0)/0x0(0) Next 0x0(0)/0x0(0)/0x0(0)
Last retransmission scan length is 0, maximum is 0
Last retransmission scan time is 0 msec, maximum is 0 msec
R2#

After configuring VL in IPv6 address family in OSPFv3

One other thing I noticed playing around with it is if I removed the global IPv6 address it was using it just went down to the next available one in the list of the remote router to attach itself to. Not sure the mechanism there or if its a virtual thing. Just interesting.

Hope this helps

-David

[M02@rt37 · Accepted solution]

Very interesting @David Ruess 

Thanks a lot for that lab !

[burhaans28 · Accepted solution]

Thank you so much @David Ruess this one really solve my query. I Really appreciate your help.