Use a Cisco Router as a DHCP client
When you connect your Cisco router’s WAN interface to upstream ISP equipment, the ISP’s equipment dynamically assigns a public IP address, a subnet mask, and a default gateway to your router. By configuring your router’s outward-facing interface as a DHCP client, it can automatically negotiate and receive this public IP address from the ISP, ensuring you have Internet connectivity even if the ISP changes your IP address later.
1. Configuration
Section titled “1. Configuration”1.1 Enter the specific interface connected to the ISP/upstream network:
Section titled “1.1 Enter the specific interface connected to the ISP/upstream network:”Router(config)# interface GigabitEthernet0/01.2 Set the IP address to be assigned via DHCP:
Section titled “1.2 Set the IP address to be assigned via DHCP:”Router(config-if)# ip address dhcp