MPLS load balancing

[accraig]

If I have 2 lines terminating on a single router within a VRF called INTERNET and I have load sharing per packet on either interface with a default route down either link......is it possible for me to export both default routes to another VRF called TEST on the same router using a single RT, so that vrf TEST will see equal cost default routes?

I have used maximum-paths command, however I still see only one of the default routes.

[ebreniz]

Routes from one VRF cannot be exported or inserted into another VRF on the same router. If this is what is being tried, it will not work since it is designed to work this way to provide isolation. I don't understand what is meant by "I have used maximum-paths command, however I still see only one of the default routes."

More information may be required.

[ng-hlong]

you can still use route leaking mechanism to insert routes from one VRF to the other on the same router.

However, there's only one default route

[romccallum]

you need to use the mpls default-route command and also you need to propogate the default-route within bgp with another command which I hope you know already :-)

[accraig]

So let me get this straight. With the added global command of "mpls ip default-route" this should assign a different label to either default route and thus when the INTERNET vrf RT is imported into the TEST vrf I should see 2 equal cost default routes in the TEST vrf.....not just one selected by BGP??

[ng-hlong]

I checked it in the Lab & still see only one default route in TEST vrf.

[mheusinger]

Well there are some points to be considered: what are the RDs in the two VRFs?

If they are different, then you will need

router bgp 65000

address-family ipv4 vrf TEST

maximum-path ibgp 2 import 2

explanation:

a) maximum-path 2 ("the well known") is for eBGP only. And you do not have eBGP between your PEs

b) maximum-path ibgp 2 is for iMBGP routes. So IF there are two entries with equal metric in your VRF BGP table, THEN you will see both in the routing table.

c) maximum-path import 2

This makes sure that you have two entries in your VRF BGP table. By default only one VPNv4 NLRI is imported into a VRF, even if you have more available.

Having only one entry in the BGP table leads to b) doing nothing.

Could you test that and post the results?

Kind regards

Martin

[sshang2]

So does this mean, it is possible that the ipv4 routes from one local VRF-1 can be "leaked" to another local VRF-2 if VRF-2 is provisioned to import the route with the appropriate RT from VRF-1?

Would you please confirm? And, is there any sample configuration/document to illustrate it from Cisco? Thanks!

SShang