[c-nsp] Route Leaking and next-hop recursion

[Sami Joseph]

Hi All,



I need to reinforce my understanding of how route leaking from a VRF to
global works, I was not able to find a decent document using Google.



Network topology:
http://www.postyourimage.com/view_image.php?img_id=GpgBT3FzVRxuuE81218144855



On the 6500 switch, I created Vlans and SVIs like the following:



*interface Vlan20*

*ip address 10.5.5.73 255.255.255.248*



And on interface vlan 40, I added a VRF



*int vlan40*

*ip vrf forwarding 3G*

*ip address 10.0.0.1 255.255.255.252*



Then I want the routes inside this VRF to access the IP addresses behind
VLAN20 as depicted in the diagram : (1.1.1.10 and 1.1.1.11)



So I need to do leaking from global to vrf and the path back from vrf to
global:



*ip route vrf 3G 1.1.1.10 255.255.255.255 10.5.5.74 global*



And: (assuming the networks on the yellow cloud are 8.8.8.0)



*ip route 8.8.8.0 255.255.255.0 vlan40*





This way, I guaranteed that packets destined from the VRF to global will go
to their next-hop which is directly connected to the switch (10.5.5.74) and
I suppose route recursion should be able to find where the next-hop is.



When we opened a ticket for this, we were told that with this setup, CEF is
not going to be able to create a valid adjacency and so an arp request will
be sent for each packet destined to 10.5.5.74 without a reply.



Why cant CEF install an entry for 10.5.5.74, why cant route recursion work?



Thanks,

Sam