OSPF and Frame Relay Multipoint

GrayhenTorGrayhenTor Posts: 43Member ■■□□□□□□□□
Hi,
I just setup a lab with a Frame Relay switch in the middle, then "R1" as a 'hub' with point-to-point subinterfaces to 'spokes' R2 and R3. All works well. Then I added OSPF routing to these and found that I had to use "ip ospf network broadcast" in order for OSPF adjacencies to form.
Then I added a multipoint subinterface to R1 to connect to two additional routers R4 and R5 in the same IP subnet. All this is working well in the Frame Relay and IP sense..
But... I can't get these two routers to join in OSPF routing with the other three. I guess it's all down to using the right combination of "ip ospf network..." commands. I've experimented with "point-to-multipoint" , "non-broadcast" etc but no luck yet
Anyone know what command I should use where ?

I've attached a diagram .. hope u can see it..

Many thanks!

Comments

  • billscott92787billscott92787 Posts: 933Member
    You do not have to use that! I GUARANTEE THAT you forgot one thing. When using OSPF over frame-relay you are using it over a non-broadcast network. By default OSPF over NBMA doesn't advertise hellos unless it knows "who" to advertise them to (as opposed to an ethernet or broadcast network) That's why it worked when you used the broadcast network. When you configure OSPF over an NBMA you have to use the neighbor x.x.x.x command to define the address of the neighboring router. So if your neighboring router was 172.12.1.1 255.255.255.0



    router ospf 1
    network (whatever)
    neighbor 172.12.1.1

    Then you will see the adjacency come up. Hope this helps ya out :)
  • GrayhenTorGrayhenTor Posts: 43Member ■■□□□□□□□□
    Thanks both of you ! That was a very useful tutorial page, captobvious. In the end it was the missing neighbor x.x.x.x commands that did the trick and all routers are now playing together for OSPF. The two in the NBMA network that need the neighbour commands seem to take a few minutes longer to form adjacencies than the other three - not sure why that is ... but the main thing is it works.
    I think I've stepped a little bit beyond what I need to know for CCNA with this one, which is a good thing. Frame Relay filled me with dread before but now I think I have lab'ed it into submission :)

    Thanks again !
  • stlsmoorestlsmoore Posts: 515Member ■■■□□□□□□□
    GrayhenTor wrote: »
    Thanks both of you ! That was a very useful tutorial page, captobvious. In the end it was the missing neighbor x.x.x.x commands that did the trick and all routers are now playing together for OSPF. The two in the NBMA network that need the neighbour commands seem to take a few minutes longer to form adjacencies than the other three - not sure why that is ... but the main thing is it works.
    I think I've stepped a little bit beyond what I need to know for CCNA with this one, which is a good thing. Frame Relay filled me with dread before but now I think I have lab'ed it into submission :)

    Thanks again !

    That's a good thing, it will come in handy when you get to the CCNP material....trust me.
    My Cisco Blog Adventure: http://shawnmoorecisco.blogspot.com/

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  • billscott92787billscott92787 Posts: 933Member
    You will get very familiar with the neighbor command, especially once you get to the CCNP material if you move on beyond the CCNA. It is used with OSPF as well as all BGP configurations. I think you can use it with EIGRP and RIP over NBMA networks as well.
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