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

[Peter Rathlev]

On Fri, 2008-08-08 at 00:59 +0300, Sami Joseph wrote:
<cut>
> *interface Vlan20*
> *ip address 10.5.5.73 255.255.255.248*
> 
<cut>
> *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?

Just a shot in the dark, but would it help to add an interface to the
vrf route statement? Like this:

ip route vrf 3G 1.1.1.10 255.255.255.255 Vlan20 10.5.5.74 global

Regards,
Peter