How to Configure Static NAT

Static Network Address Translation (NAT) is a technique that translates private IP addresses into public IP addresses. To configure Static NAT, an administrator needs to manually map each IP address individually. This technique is typically helpful for a small network that contains the limited number of hosts. In this post, we will explain how to configure Static NAT on Cisco router.

We will use the following topology to configure Static NAT. You can use either Cisco Packet Tracer or GNS3 simulator, depending on your choice, to create the following topology.Configure Static NAT in CiscoBefore to configure Static NAT, ensure that you have configured appropriate IP addresses on the devices mentioned in the topology. In addition, you also need to perform a routing algorithm. You can use any of the routing algorithms depending on your choice. If you face any problem to configure IP addresses and routing, please refer the following links.

Steps to Configure Static NAT

To configure Static NAT, you need to perform the following steps:

  1. On Router1, execute the following command to specify the inside interface that is Fa0/0.
Router1(config)#int fa0/0
Router1(config-if)#ip nat inside
  1. Next, execute the following command to specify the outside interface that is Fa0/1.
Router1(config)#int fa0/1
Router1(config-if)#ip nat outside
  1. Once, you have defined the inside and outside interfaces, now you need to specify the private IP addresses that need to be translated into the public IP addresses. In this case, we will translate private IP address into public IP address. To do so, execute the following command.
  • Router1(config)#ip nat inside source static
  1. The following figure shows how to configure static NAT on a router.Configure Static NAT in Cisco Router
  2. Once, you have configured Static NAT, now it’s time to verify your configuration.
  3. To verify the static NAT configuration, open Command Prompt on PC0, type ping Leave the Command Prompt active.
  4. Move on to Router1 and type the following command to view the NAT translation table.
Router1#show ip nat translations

show ip nat translation command

In the preceding figure, you can see that private IP address has been translated into public IP address.

Removing NAT Configuration

If you have mapped a wrong IP address or want to disable the NAT translation for any reason, execute the following command.

  • Router1(config)#no ip nat inside source static

In this post, we have explained how to configure Static NAT. Hope, it helped you. Please subscribe our blog to get updated posts and also share to others if you think it can help other too. We would also appreciate you if you provide your valuable suggestions and feedback.


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