CCNP - VRF
Hello,
Just watched the episode on VRF in the CCNP series. VRF is new to me so please forgive me if the answer to my question is obvious.
Assuming two customers (two VRF instances) share a network (for example, 192.168.0.0/24) - and assuming the ISP router is natting both 192.168.0.0/24 networks to the Internet - how does the ISP router distinguish the xlates?
This might be beyond the scope of the CCNP material, but I am curious.
Regards,
Rob Clifton
This is not as obvious an answer as you might think. Normally, we're not really using NAT with VRFs. Usually when using VRFs, it's along with MPLS which is attaching the labels to the traffic from our VRFs. So NAT is not normally involved.
If you're trying to do this VRFLite (without MPLS), then you would have to implement NAT but with NVIs instead of using the traditional nat inside and outside configuration. with the overload keywords.
When you do that you'll see from debugging NAT on your router what the ISP will see which are the two public IP addresses sending data and the router NAT translations working just fine
You'll also need 2 separate IP facing the ISP too. But at this point, you might as well just configure VLANs instead.
Thanks, Ronnie!
