Purpose

In this lab, we used Cisco Packet Tracer to implement NAT for Champlain and its CNCS labs.

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IP Configuration

First, we configured IP addresses and gateways for all of the PCs and servers on the network. We started with the Foster and Skiff PCs.

Foster PCs 1 and 2 were configured IP addresses of 192.168.3.2 and 192.168.3.3, respectively, as well as configured with the default gateway of 192.168.3.1.

Skiff PCs 1 and 2 were configured IP addresses of 192.168.1.2 and 192.168.1.3, respectively, as well as configured with the default gateway of 192.168.1.1.

For the Ireland servers, the internal server and the pub web server were configured IP addresses of 192.168.7.2 and 192.168.7.3, respectively, as well as configured with the default gateway of 192.168.7.1.

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PAT Configuration

Next, we configured PAT on the CC Border Router to allow Foster and Skiff PCs to ping the BT server. Lab 6-2 on PAT configuration will be a helpful reference here.

To start, we defined the FastEthernet0/0 (192.168.100.1) and FastEthernet0/1 (219.93.144.1) ports as the inside and outside of the NAT network, respectively.

Then we created an address pool called pat that would be used by the Foster and Skiff PCs as public IP addresses. In this case, the IP address included in the pool was 219.93.144.120.

For the address pool, we created an access-list for the internal IPs that would be allowed to use the public IP of 219.93.144.120. In other words, the Foster and Skiff PCs.

Lastly, we assigned the address pool and the access rule to the interfaces with an NAT statement which would translate the IPs of the Foster and Skiff PCs to 219.93.144.120 when they go from inside to outside of the network.

If configured correctly, the Foster and Skiff PCs should be able to ping the BT server.

At the same time, running the command show ip nat translations on the CC Border Router should display the working NAT in a table format.

In addition, we used the command copy run start to save these configuration changes so they would not be lost when closing the file.

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Static NAT Configuration

After this, we configured static NAT on the CC Border Router to allow the BT server to access the Ireland public web server. Lab 6-1 on static NAT configuration will be a helpful reference here.

First, we defined the FastEthernet0/1 (219.93.144.1) and FastEthernet0/0 (192.168.100.1) ports as the inside and outside of the NAT network, respectively.

Then we created a static rule associated with the web server's private IP address and public IP address, respectively.

If configured correctly, it should now be possible to ping the web server's private IP address of 219.93.144.121.

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Troubleshooting

One specific issue occurred with the static NAT configuration that prevented me from pinging the Ireland public web server from the BT server. For all of my pings, I attempted PDUs between the two servers and received Failed statuses. However, by repeating the pings in the command prompt of the BT server, I was eventually able to get successful results. This might have been a networking issue that did not allow me to send PDUs between the two servers when performing pings, however this workaround allowed me to get the results I was looking for.

On a different note, I also had a number of extra access rules in my show ip nat translations table due to attempting to configure multiple access rules in response to my situation with the first issue. Although these additional access rules did not prevent me from pinging the two servers or interfere with my static NAT configuration, I removed each of them with the no <IP_NAT_Rule_Goes_Here> command in the config terminal of the CC Border Router to clean things up.