Route Leaking Between VRFs

[Jose Campos]

Hi Guys. 

I've been reading and testing, but haven't got to the right solution yet. Let image you have 3 VRFs

vfr_A

vfr_B

vfr_A

This VRFs terminate in some datacenter router, and they need to access the a group of networks behind that device:

1.0.1.0/24

1.0.2.0/24

1.0.3.0/24

Now, to route this traffic inside the VRF to remote hosts, static routes are created and distributed to other routers, ex:

ip route vfr_A 1.0.1.0 /241.1.2.2

ip route vfr_B 1.0.1.0 /24 1.1.3.2

ip route vfr_C 1.0.1.0 /24 1.1.4.2

Now, of course that this model doesn't scale, and my question is :

Would it be possible to somehow group the DC networks, like in a prefix list, and anounce them to all VRFs? I know this can be done, but how can i overcome the fact that the last hop is different per VRF (1.1.2.2, 1.1.3.2, 1.1.4.2).

Thanks for the help.

Jose

[Mark Pace Balzan]

Hello Jose

Let me share my thoughts with you below

In each vrf so vrf_a, vrf_b, vrf_c you need to import the /24 prefixes into the vrf. In iOS you can use a route map matching the rt

This means that they must be first exported. Exporting from another vrf, which would be your data centre if I understand correctly is also straight forward.  Exporting from global is not so easy and if this is the case you probably need to create a loopback cable between two interfaces one in global and another interface inside a vrf say vrf_d and export from there.

Let me know if this helps or if it's not clear 

Mark

[Jose Campos]

Thanks for the help.

Best regards

Jose

[Giuseppe Larosa]

Hello Jose,

inter VRF redistribution can be achieved by playing with route targets extended communities attributes.

This is the more powerful and scalable way to do this and you don't need any physical cable to join the VRFs.

Hope to help

Giuseppe