Re: Routing Issues Using OSPF

rickjbeats · ‎07-05-2013

We are in the process of using AT&T's switched ethernet to transport. They're using a single VLAN tag to carry traffic from our 70 locations back to the core. I have a 4506 at the distribution and 6509 at the core.

To simply, I have an IP address on the VLAN that AT&T is tagging that is responsible for forwarding traffic. Using OSPF, I have the additional routes summarized that are associated with different VLANs. Here is the output.

Here's the problem, when I do a traceroute from a device that's on a different VLAN besides the vlan that's tagged on the AT&T ASE network, it fails. It's failing at the 4506 and never makes it to the Core at the Data Center b/c the default VLAN being used is not the tagged VLAN.

Of course, on the EIGRP network that uses AT&T managed services, I can traceroute and see hops to the core and then internet.

If you can shed some light on this, please let me know. Thanks. By the way, the routes are all learned and can be seen properly. I also noticed that I cannot telnet using the 3.3.3.x network unless I'm directly on the Core.

Output from Core

6509#sh ip route ospf 1 <------ CORE Switch

10.0.0.0/8 is variably subnetted, 150 subnets, 7 masks

O IA 10.11.0.0/16 [110/2] via 3.3.3.11, 02:07:29, Vlan8

O IA 10.2.0.0/16 [110/2] via 3.3.3.2, 02:07:29, Vlan8

O 10.0.0.0/8 is a summary, 02:40:49, Null0

O IA 10.26.0.0/16 [110/2] via 3.3.3.26, 02:07:29, Vlan8

O IA 10.30.0.0/16 [110/2] via 3.3.3.30, 02:07:29, Vlan8

O IA 10.23.0.0/16 [110/2] via 3.3.3.23, 02:07:29, Vlan8

O IA 10.58.0.0/16 [110/2] via 3.3.3.58, 02:07:29, Vlan8

O IA 10.63.0.0/16 [110/2] via 3.3.3.63, 02:07:29, Vlan8

O IA 10.77.0.0/16 [110/2] via 3.3.3.77, 02:07:29, Vlan8

O IA 10.65.0.0/16 [110/2] via 3.3.3.65, 02:07:29, Vlan8

cpsb-6509#

Output from Remote Location

10.0.0.0/8 is variably subnetted, 24 subnets, 7 masks

O IA 10.0.0.0/8 [110/2] via 3.3.3.253, 02:10:09, Vlan8 <------ CORE

O IA 10.2.0.0/16 [110/2] via 3.3.3.2, 02:10:09, Vlan8

O IA 10.11.0.0/16 [110/2] via 3.3.3.11, 02:10:09, Vlan8

O IA 10.23.0.0/16 [110/2] via 3.3.3.23, 02:10:09, Vlan8

O IA 10.26.0.0/16 [110/2] via 3.3.3.26, 02:10:09, Vlan8

O IA 10.30.0.0/16 [110/2] via 3.3.3.30, 02:10:09, Vlan8

O 10.58.0.0/16 is a summary, 04:01:10, Null0

O IA 10.63.0.0/16 [110/2] via 3.3.3.63, 02:10:09, Vlan8

O IA 10.65.0.0/16 [110/2] via 3.3.3.65, 02:10:09, Vlan8

O IA 10.77.0.0/16 [110/2] via 3.3.3.77, 02:10:09, Vlan8

4506#

Rolf Fischer · ‎07-06-2013

Hi Rickey,

I also noticed that I cannot telnet using the 3.3.3.x network unless I'm directly on the Core

the next-hop addresses for the IA-routes belong also to the 3.3.3.0/24 network, so it seems like there's a reachability problem to VLAN 8 from the networks you have summarized.

From another VLAN, can you ping the local VLAN 8 IP (e.g. 3.3.3.253 at the core's site)?

Where is the default-route pointing to?

From the core, can you ping a remote VLAN 8 IP with when you set the source IP to another VLAN?

(e.g. ping 3.3.3.58 source vlan 5 if a SVI for VLAN 5 exist)

Could you also provide the outputs of

show ip ospf interface vlan 8
show ip ospf | b Area

from the core and one remote location?

Regards

Rolf

rickjbeats · ‎07-06-2013

Problem was I forgot to set the default-information under the OSPF process. Once I did that, the gateway of last resort showed up on all remote locations and we were able to reach the edge.

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