Objective
Configure Static NAT to map a localized inside private IP address to an outside public IP address.
Lab Topology
| Device | Interface | IP Address | Subnet Mask | Description |
|---|---|---|---|---|
| R1 | GigabitEthernet0/0 |
192.168.1.1 |
255.255.255.0 |
Inside Local (LAN Gateway) |
| R1 | GigabitEthernet0/1 |
203.0.113.2 |
255.255.255.252 |
Outside Global (WAN Link) |
| Local Server | NIC |
192.168.1.10 |
255.255.255.0 |
Internal Server mapped to 203.0.113.10 |
| ISP Router | GigabitEthernet0/0 |
203.0.113.1 |
255.255.255.252 |
Internet Gateway Simulator |
Task 1 - Basic Configuration
Apply hostname and disable DNS lookup.
Router> enable Router# configure terminal Router(config)# hostname R1 R1(config)# no ip domain-lookup
Task 2 - Define Interfaces and IP Addressing
Configure interface IP addresses and assign inside and outside interfaces for NAT.
R1(config)# interface gigabitEthernet 0/0 R1(config-if)# ip address 192.168.1.1 255.255.255.0 R1(config-if)# no shutdown R1(config-if)# ip nat inside R1(config-if)# exit R1(config)# interface gigabitEthernet 0/1 R1(config-if)# ip address 203.0.113.2 255.255.255.252 R1(config-if)# no shutdown R1(config-if)# ip nat outside R1(config-if)# exit
Task 3 - Configure Static NAT
Create a static NAT translation mapping an internal server to a public IP address.
R1(config)# ip nat inside source static 192.168.1.10 203.0.113.10
Task 4 - Verification
Check the NAT translation table to ensure the static entry exists.
R1# show ip nat translations Pro Inside global Inside local Outside local Outside global --- 203.0.113.10 192.168.1.10 --- ---