OSPF Neighbor Relationship not showing up over VL, but VL showing up

Hi Guys,

I have seen a couple of times -literally- when
configuring a Virtual Link and issuing "show ip ospf neighbors", that
the neighbor relationship over the Virtual-Link is not showing up;
however, when I issue "show ip ospf virtual  links" the status of the VL
is UP and it displays "run as on-demand circuit". One of these two
occurrences was because I (mis)configured the VL the following way:

area 0 virtual-link x.x.x.x

Then I changed it to the correct
transit area and the OSPF neighbor relationship over the VL came up.
However, the second time I faced this issue I couldn't figure what I was
doing wrong, and everything seemed to be correct. I couldn't sort this
out. I am sorry I don't have those configurations with me anymore, but I
would like to know if anybody could provide any pointers as to why this
might happen (the adjacency not forming over the VL, but the VL showing up), the possible
causes surrounding this behavior.

I appreciate your help.


  • Jorge,


    Ensure you are using the correct transit area and also using the router-id's of the neighbors.




  • Jorge,

    A virtual-link will show as a demand link - no hello traffic is sent over the virtual-link.

    As Ediwnrg00 pointed out, the endpoint is always the router-id of the target router.

    If you are configuring a virtual-link over Area 0, there is no need for a virtual-link. The virtual-link transports area 0 adjacency over non-area 0 links.

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