MPLS on 12.2T and Inter-AS VPN issue

[owaisberg]

Trying to connect 2 PEs and one ASBR in one AS to second AS with one ASBR and one PE:

AS1

PE1 ---- PE2

\ /

ASBR1

|

|

ASBR2

|

PE2

AS2

One of the PEs in the AS1 running 12.2T on c3640 and as it looks like doesn't inject its neighboring PEs/ASBR tags into TFIB which makes VPN connected to it unaccessible. Second PE in the same AS1 has identical config and full Inter-AS connectivity. As well PE1 cannot get to VPN on PE2 (due to reason above). PE2 from AS2 can get to VPN on PE1 in AS1. Configs on all PEs are identical, control plane is fine so the only problem is with that 12.2 router.

How can I make it work on 12.2T PE without performing IOS upgrade ?

Thanks.

OW

[owaisberg]

Hi,

Looks like all TDP adjacencies (ASBR and other PE run TDP) are okay so I don't see the

reason of putting both protocols in place.

Please see the attachmnet

ASBR-AS1:

sh mpls ldp discovery

Local LDP Identifier:

146.11.4.4:0

Discovery Sources:

Interfaces:

FastEthernet0/0.24 (tdp): xmit/recv

TDP Id: 146.11.2.2:0

FastEthernet0/0.34 (tdp): xmit/recv

TDP Id: 146.11.8.8:0 <- PE2-AS1

[swaroop.potdar]

Hi Oleg,

To understand the problem much better,can you take the output as below all all the PE routers.

1) show ip bgp vpnv4 all

2) show mpls forwarding

3) show mpls ldp discovery

Please execute all these commands on all the routers.

[owaisberg]

Here we are. One thing though...I changed

TDP to LDP in AS1. Just to let you know.

Thanks.

[swaroop.potdar]

Well..You have a very peculiar scenario indeed. You dont have any IGP labels in your forwarding table.

Ok, now this scenario somewhat has no relevance with your poster INTER_AS. but anyways, you can paste in the output of

"show ip cef 146.11.2.2 detail"

"show ip cef 146.11.4.4 detail"

HTH-Cheers,

Swaroop

[owaisberg]

Yes, I see that too...somehow 12.2T doesn't want assign labels to these two routes learned from ISIS. Outputs attached.

I've tried static bindings...looks good on output but local VRF still not reachable

[swaroop.potdar]

Hi Oleg,

Can u attach,

a) "show ip cef detail"

b) "show ip route"

from PE2-AS1 & ASBR-AS1

HTH-Cheers,

Swaroop

[owaisberg]

Hi,

I guess I'm giving up on this stage now....

it looks like an obvious bug: routes are in

FIB but labels for them are not generated.

As soon as I put any other IOS higher than

12.2(11)T11 this issue is gone automatically.

Looks like most of 12.2 are afected with all

kind of MPLS related issues/bugs.....another one I've seen on 12.2T15 is when all labels

disappear from LFIB as soon as vrf NAT activated and 0.0.0.0/0 get sent over vrf

address family towards remote PEs.