Configure NAT/PAT

[TS40]

 I have a problem. I want to apply nat/pat (it is a requirement) so that my PC's can ping to the address 64.100.100.10 (in the green part) and that from the yellow part my PC can also ping to the address 64.100.100.10. The routing protocol that i already configured is OSPF (it is a requirement). Can you please put the commands that u use  in the packet tracer?

[Flavio Miranda · Accepted solution]

Hello @TS40 

  To put the NAT in place you need an

access list

matching the traffic. As you have  4 different networks, you can use an ACL like this

access-list 1 permit 192.168.0.0 0.0.255.255

This ACL will match all your LAN traffic. Apply this ACL to R2.

Then, you need to add the command

ip nat inside

in all R2´s interfaces except Gi0/0

On the interface Gi0/0 you appy the command

ip nat outside

Last you use the NAT statement which is

ip nat inside source list 1 interface

GigabitEthernet0/0

overload

But, there´s one more thing you are going to need in order to ping the IP 64.100.100.10, which is let the network know that it exist.

You can do this on the R2 OSPF process by adding one of the following command

router ospf  1

redistribut static subnets

OR

router ospf 1

default-information originate

Both command will tell to others routers that the IP address 64.100.100.10 exist behind R2.

Attaching my file for your reference.

To check the NAT use the command

show ip nat translations

R2#sh ip nat translations

Pro Inside global Inside local Outside local Outside global

icmp 209.165.200.225:17192.168.30.2:17 64.100.100.10:17 64.100.100.10:17

icmp 209.165.200.225:18192.168.30.2:18 64.100.100.10:18 64.100.100.10:18

icmp 209.165.200.225:19192.168.30.2:19 64.100.100.10:19 64.100.100.10:19

icmp 209.165.200.225:20192.168.30.2:20 64.100.100.10:20 64.100.100.10:20