Hi,
I'm attempting to adapt a scenario from the MPLS and VPN Architecture CCIP edition book. The scenario that I'm working with has two PE/P IOS XR routers in a collapsed MPLS core. All customers are terminated in their own VRF on each PE/P router. I want to be able to terminate multiple Internet providers on the PE/P routers as a cost-cutting measure and the question I'm trying to solve is how to route the customer traffic to the Internet.
Page 233 of the MPLS and VPN Architecture CCIP edition book lays out the possibility of using default route that generates an aggregate label thus forcing the PE to perform a lookup in the Internet VRF prior to forwarding the packet. I've set up this scenario in a lab whereby the Internet VRF on the left PE/P router has a static default configured pointing at a loopback address in the VRF. The Left PE/P progagates the default through MPBGP using the network 0.0.0.0 command. All customer VRFs that require internet access receive the default. When customer traffic on the right PE/P is forwarded to the Internet VRF by the default, forwarding works - the aggregate lable forces a lookup to be performed in the Internet VRF where full Internet routes exist and the packet is forwarded using the best path. The problem is that customer traffic using the default route from the left PE/P router is blackholed. The aggregate lookup doesn't work and the customers terminated on the left PE/P do not have Internet access. The scenario in the book is using a third router attached to each PE to distribute the aggregate default route. Is it possible to make it work without requiring a third device to propagate the MPLS aggregate labelled default route?
The basic configs are below:
Right PE:
vrf VRF_TEST
address-family ipv4 unicast
import route-target
555:5555123
555:5555555
!
export route-target
555:5555555
!
!
!
router bgp 65005
vrf VRF_TEST
rd 555:5555555
address-family ipv4 unicast
redistribute connected
RP/0/RSP0/CPU0:RouterRight#sho route vrf VRF_TEST
Gateway of last resort is 192.168.1.1 to network 0.0.0.0
B* 0.0.0.0/0 [200/0] via 192.168.1.1 (nexthop in vrf default), 00:00:29
L 192.168.202.1/32 is directly connected, 18:01:24, Loopback5555
Left PE:
vrf VRF_INET_TEST
address-family ipv4 unicast
import route-target
555:5555555
!
export route-target
555:5555123
vrf VRF_TEST
address-family ipv4 unicast
import route-target
555:5555123
555:5555555
!
export route-target
555:5555555
!
!
!
router bgp 65005
vrf VRF_INET_TEST
rd 555:5555123
address-family ipv4 unicast
network 0.0.0.0/0
redistribute connected
router bgp 65005
vrf VRF_TEST
rd 555:5555555
address-family ipv4 unicast
redistribute connected
!
!
!
router static
vrf VRF_INET_TEST
address-family ipv4 unicast
0.0.0.0/0 Loopback5555
interface Loopback5555
vrf VRF_INET_TEST
ipv4 address 192.168.200.1 255.255.255.255
RP/0/RSP0/CPU0:RouterLeft#sho route vrf VRF_TEST
Gateway of last resort is 0.0.0.0 to network 0.0.0.0
B* 0.0.0.0/0 is directly connected, 00:03:09, Loopback5555 (nexthop in vrf VRF_INET_TEST)
B 192.168.200.1/32 is directly connected, 17:34:46, Loopback5555 (nexthop in vrf VRF_INET_TEST)
L 192.168.201.1/32 is directly connected, 18:07:59, Loopback12345
RP/0/RSP0/CPU0:RouterLeft#sho route vrf VRF_INET_TEST
Gateway of last resort is 0.0.0.0 to network 0.0.0.0
S* 0.0.0.0/0 is directly connected, 00:03:25, Loopback5555
L 192.168.200.1/32 is directly connected, 18:13:17, Loopback5555
B 192.168.201.1/32 is directly connected, 17:35:02, Loopback12345 (nexthop in vrf VRF_TEST)
B 192.168.202.1/32 [200/0] via 192.168.1.2 (nexthop in vrf default), 18:04:21
B <Full Table of Internet Routes - Snipped>
