Redistribution of eBGP routes into OSPF

[starbearer]

Hi,

We have a few Hub offices A and B running on MPLS (eBGP) with the provider and other branch offices C and D running on OSPF (IPSEC over Internet). A new MPLS site came up, E,  but it has not internet connection yet. I'm trying to make this site reachable to the OSPF offices. I redistributed the route learnt via BGP for the new office into OSPF and it is being learnt too. I just cant seem to forward traffic to it. The trace just shows traffic reaching the main hub office but going nowhere after that.     

So basically, E is reachable from A and B over MPLS. A and B are reachable to C and D over OSPF. But E is not reachable to C and D.

Also, the reverse is working. From E, I can reach C and D. Traffic comes to A and then goes out through the Tunnels. In the forward, from C and D, traffic comes to A and then nothing happens.

What could be wrong? Please help.     

[paul driver]

Hello

Could you post a simple topology so I can and maybe others can visualize the setup?

res

Paul

Please don't forget to rate any posts that have been helpful.

Thanks.

[starbearer]

Simple topology attached

[paul driver]

Hello

Can you see Hubs E routes in OSPF?

Would post the route table for this and maye some trace routes

res

Paul

Please don't forget to rate any posts that have been helpful.

Thanks.

[mfurnival]

C and D have visbility of A and B subnets because they all participate in OSPF. C and D have no vsibility of E subnet because E does not participate in OSPF. What you would need to do is allow for redistribution between OSPF and BGP. In your diagram do A and B represent a site or a single device? i.e. at site A and B do you have 1 router doing both BGP and OSPF or mutliple routers?

[starbearer]

I now added static route on C and D for E's subnet. It points to the tunnel which C and D have with A. Even now, it doesnt go ahead than A.

To answer your questions:

@pdriver: yes, I could

@mfurnival: Both A and B have one router which do both OSPF and BGP. A and B are different sites on the MPLS. they are running BGP with the provider router and learning each other's as well as E's routes through the BGP with the provider.

[starbearer]

Another update: I added a static route for C, on A's GRE Tunnel interface (ip route Tunnel-interface-to-site-C) and it started working. C is able to reach E now. How?? Why??

[paul driver]

Hello

You haven't posted any routes table outputs to understand the reachability but if if now works congratulations - I guess adding the statics
Established connectivity

Res
Paul

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