Enable a Router to Become a DHCP Client

A.

If we want to get an IP address from the DHCP server on a Cisco device, we can use the command ip address dhcp.

Note: The command ip helper-address enables a router to become a DHCP Relay Agent.

The command that enables a router to become a DHCP client is option B, "ip dhcp client."

When a router is configured as a DHCP client, it sends a broadcast message requesting an IP address and other configuration parameters from a DHCP server on the network. The DHCP server then assigns an IP address to the router and provides additional network configuration information, such as the default gateway, subnet mask, and DNS server addresses.

Here's a brief explanation of the other options:

• Option A, "ip address dhcp," is used to configure a router interface to obtain an IP address from a DHCP server. This command tells the router to use DHCP to obtain its own IP address, rather than assigning a static IP address.
• Option C, "ip helper-address," is used to forward DHCP requests from clients on one network to a DHCP server on another network. This command is typically used in a multi-subnet environment where DHCP clients are located on a different subnet than the DHCP server.
• Option D, "ip dhcp pool," is used to define a DHCP address pool on a DHCP server. This command is used to specify the range of IP addresses that the DHCP server can assign to clients, along with other configuration parameters.