Concept Guide

Congure the System to be a DHCP Client
A DHCP client is a network device that requests an IP address and conguration parameters from a DHCP server.
Implement the DHCP client functionality as follows:
• The switch can obtain a dynamically assigned IP address from a DHCP server. A start-up conguration is not received. Use bare metal
provisioning (BMP) to receive conguration parameters (Dell EMC Networking OS version and a conguration le). BMP is enabled as
a factory-default setting on a switch.
A switch cannot operate with BMP and as a DHCP client simultaneously. To disable BMP in EXEC mode, use the stop bmp command.
After BMP stops, the switch acts as a DHCP client.
• Acquire a dynamic IP address from a DHCP client is for a limited period or until the client releases the address.
• A DHCP server manages and assigns IP addresses to clients from an address pool stored on the server. For more information, refer to
Conguring the Server for Automatic Address Allocation.
• Dynamically assigned IP addresses are supported on Ethernet, VLAN, and port-channel interfaces.
• The public out-of-band management interface and default VLAN 1 are congured by default as a DHCP client to acquire a dynamic IP
address from a DHCP server.
• By default, the switch is congured to operate in BMP mode as a DHCP client that sends DHCP requests to a DHCP server to retrieve
conguration information (IP address, boot-image lename, and conguration le). All ports and management interfaces are brought up
in Layer 3 mode and pre-congured with no shutdown and no ip address. For this reason, you cannot enter conguration
commands to set up the switch. To interrupt a BMP process, prevent a loop from occurring, and apply the Dell EMC Networking OS
image and startup conguration stored in the local ash, enter the
stop bmp command from the console. To recongure the switch
so that it boots up in normal mode using the Dell EMC Networking OS image and startup conguration le in local ash, enter the
reload-type normal-reload command and save it to the startup conguration:
DellEMC# reload-type normal-reload
DellEMC# write memory
DellEMC# reload
• To re-enable BMP mode for the next reload, enter the reload-type jump-start command.
• If the management port is associated with any non-default VRF, then the ip address dhcp command does not work.
Conguring the DHCP Client System
This section describes how to congure and view an interface as a DHCP client to receive an IP address.
Dell EMC Networking OS Behavior: The ip address dhcp command enables DHCP server-assigned dynamic addresses on an
interface. The setting persists after a switch reboot. To stop DHCP transactions and save the dynamically acquired IP address, use the
shutdown command on the interface. To display the dynamic IP address and show DHCP as the mode of IP address assignment, use the
show interface type slot/port[/subport] command. To uncongure the IP address, use the no shutdown command
when the lease timer for the dynamic IP address is expired. The interface acquires a new dynamic IP address from the DHCP server.
To congure a secondary (backup) IP address on an interface, use the ip address command at the INTERFACE conguration level.
Use the no ip address dhcp command to:
• Release the IP address dynamically acquired from a DHCP server from the interface.
• Disable the DHCP client on the interface so it cannot acquire a dynamic IP address from a DHCP server.
• Stop DHCP packet transactions on the interface.
When you enter the release dhcp command, the IP address dynamically acquired from a DHCP server is released from an interface.
The ability to acquire a new DHCP server-assigned address remains in the running conguration for the interface. To acquire a new IP
address, use the
renew DHCP command in EXEC Privilege mode or the ip address dhcp command in INTERFACE Conguration
mode.
Dynamic Host
Conguration Protocol (DHCP) 327