OSPF force route

[Steffen Frederiksen]

Hi

We have our datacenter in our HQ.

From the HQ we got two 100mbit dedicated fiber connections to our branch offices. We have two 2821 routers connected to those two 100mbit connections.

Our core switches (layer 3) and the routers to the branch offices is running OSPF, right now the cores switche is having two entries in their route tables to the branch office, one entry for each 2821 router. So OSPF will do default load balancing.

I need to test the connection to one specefic branch office, called "GRI". therefore I would like all traffic to GRI going throgh one 2821 router, and that 2821 should in the test not serve the other branch offices.

How is that done, changing the administative distance to GRI on the one 2821 to something lower than the default value (110) or some policy routing?

Any suggention would be appreciated.

Best Regards, Steffen.

[samavedula_rama]

Can you possibly post a diagram depicting the scenario?

[Richard Burts]

Steffen

I agree that the topology of the network you are working with is not clear and that having a diagram would be helpful.

But I believe that the general description is adequate for us to give a general answers. I believe that you do not need to try to change administrative distance or to do Policy Based Routing to achieve your goals. I believe that you can configure ip ospf cost x on an interface to make one interface not preferred and to keep OSPF from load sharing.

To suggest what interface or what cost would require more understanding of your network topology.

HTH

Rick

[Steffen Frederiksen]

Hi

Please see attched drawing for network diagram, as you requested :-)

I would like in this test that all traffic to Branch Office 4 to go through fiber 2 from datacenter, and no other traffic on that fiber. So traffic to the other brach offices should go throgh fiber 1.

Hope it makes sense now.

[Steffen Frederiksen]

I've might come up with a solution myselvf:

Regarding to my network diagram/drawing.

What If i put 2821-02 in area 0 and 2 - and branch office 4 in area 2.

Then all traffic to Branch office 4 will be in ospf area 2 and its only 2821-02 there is in area 2....

Will it work?

[Richard Burts · Accepted solution]

Steffen

Yes I believe that it should accomplish what you need if you put office4 into OSPF area 2 and only one of the 2821 into area 2.

HTH

Rick

[Steffen Frederiksen]

Hi Rick

It worked :-)

Thank you..

Best Regards - Steffen.

[Richard Burts]

Steffen

I am glad that you got it to work and that my suggestion was helpful. It is especially nice that you came up with the solution yourself. Thank you for marking the question as resolved (and thanks for the points). It makes the forum more useful when people can read a question and can know from the marking that there was a successful resolution. You have contributed to this process of making the forum more useful.

HTH

Rick

[shah.ahmed]

I was just wondering how HO/branch offices connectivity is done. is it through sub-interfaces.

[shah.ahmed]

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@Richard Burts wrote:

Steffen

I am glad that you got it to work and that my suggestion was helpful. It is especially nice that you came up with the solution yourself. Thank you for marking the question as resolved (and thanks for the points). It makes the forum more useful when people can read a question and can know from the marking that there was a successful resolution. You have contributed to this process of making the forum more useful.

HTH

Rick

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I was just wondering how HO/branch offices connectivity is done. is it through sub-interfaces.