CSR1000v - Destination NAT

[mukundhm]

Hi,

I have a topology (attached) where I need to translate the destination IP of the outgoing packets. Here is how the flow works:

1. Host1 generates a packet with Source IP 192.168.1.2 and destination 192.168.2.2
2. Host 1 has a default route to R1 and packet is sent there.
3. R1 needs to translate the Destination IP to 10.1.2.2.

4. The packet enters R2 on a VRF. The VRF has a route to 10.1.2.0/24 network and is sent to the fabric cloud using VXLAN encapsulation. This is thee reason why destination IP needs to be translated to 10.1.2.0/24.

5. Packet enters R3 where it is decapsulated. The Source IP is 10.1.1.2 and destination is 10.1.2.2.

6. Packet is forwarded to R4. R4 translated destination IP to 192.168.2.2 

7. Packet is forwarded to Host 2.

I am looking for guidance on point 3 on how to achieve NAT of destination IP

Thanks

Mukundh

[Flavio Miranda · Accepted solution]

@mukundhm 

Change this accordingly with the topology.

R1:

interface <interface to host>
ip address x.x.x.x x.x.x.x
ip nat inside

interface <interface to R2>
ip address x.x.x.x x.x.x.x
ip nat ouside

ip nat inside source static 192.168.1.2 10.1.2.2

R4:

interface <interface to R3
ip address x.x.x.x x.x.x.x
ip nat inside

interface <interface to Host>
ip address x.x.x.x x.x.x.x
ip nat ouside

ip nat outside source static 10.1.2.2 192.168.2.2