MPLS within a VRF subinterface

[Maria Schiaffino]

Hi there,

I would like to confirm that it is not possible to configure mpls within a subinterface that belongs to a VRF.

Is it because MPLS is layer 2 and VRF is layer 3 concepts?

Configuration should look like this:

interface FastEthernet1/0.3010
 description Link to VRF-TEST
 encapsulation dot1Q 3010
 ip vrf forwarding VRF-TEST
 ip address 10.20.20.2 255.255.255.0
 mpls label protocol ldp
 mpls ip
end

But I am not able to see any ldp neighbors.

Thanks in advance!

[Nagendra Kumar Nainar]

Hi,

It is possible to configure MPLS on VRF interface (or sub-interface). it is common in CsC scenarios. Do you have LDP enabled on the other side router?.

Can you check "show mpls ldp discovery vrf <>" on the PE?.

-Nagendra

[Maria Schiaffino]

Thanks for your reply Nagendra.

Using that command I realized that I did not have a route to the other PE loopback within the VRF.  I added a static route pointing the neigh subinterface ip and LDP neighborship of the VRF came up.

I was trying to communicate 2 separate MPLS clouds (mpls configured between many devices using isis to announce their loopbacks in the global table) via this new VRF.  Each cloud connects to the other using that routed interface via layer 2 link.  The problem is how to announce the loopbacks of VRF-TEST to the other peer (only under this vrf, no the global routing table?  And as this is a lab environment, I only have loopback interfaces which are not being announced.

However, I am glad to hear that this is a possible configuration and will try to find out how to do the whole environment.

Thanks and regards,