NAT Troubleshooting

[xmorav45]

Hey guys, since my CCNA exams are closing in, I've decided to start putting it all together. Unfortunately, there seems to be an issue for which I need a little help. In the topology (included .pka), I've set up OSPF and NAT translation for both private networks. Subsequently, I issued pings from both PCs to R3 (pings were successful) to populate the translation table. Then, I tried to ping PC-2 from PC-1, which failed. With the help of the Simulation mode, I found out that the cause of the issue is that when the packet arrives at G0/0/0 on R2, the destination public IP, 144.14.20.10, is not translated back to 192.168.20.2, and subsequently, no ARP entry for 144.14.20.10 is found, and the packet is dropped.

Any help will be appreciated.
Thanks.

[paul driver · Accepted solution]

Hello
Unfortunately PT is very limited to a lot of networking features, and matching host-host NAT is one of them, which is a way of communicating between two natted domains, on a host-to-host basis.
However, in your OP as there is only a single nat host at each site then a simple 1-1 nat would be applicable.

please review working PT file example based on your OP

[xmorav45]

Hi Paul, thank you for your response. I did some research about NAT and Packet Tracer based on the limits you mentioned, and I understand now. So, thank you for pointing me in the right direction.