Reference Guide

Configure the System to be a DHCP Client
A DHCP client is a network device that requests an IP address and configuration 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 configuration is not received. Use
bare metal provisioning (BMP) to receive configuration parameters (OS version and a configuration file). 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 Configuring the Server for Automatic Address Allocation.
● Dynamically assigned IP addresses are supported on Z9500 10-Gigabit and 40-Gigabit interfaces. The DHCP client is
supported on VLAN and port-channel interfaces.
● The public out-of-band management interface and default VLAN 1 are configured by default as a DHCP client to acquire a
dynamic IP address from a DHCP server.
DHCP Client on a Management Interface
These conditions apply when you enable a management interface to operate as a DHCP client.
● The management default route is added with the gateway as the router IP address received in the DHCP ACK packet. It is
required to send and receive traffic to and from other subnets on the external network. The route is added irrespective when
the DHCP client and server are in the same or different subnets. The management default route is deleted if the
management IP address is released like other DHCP client management routes.
● ip route for 0.0.0.0 takes precedence if it is present or added later.
● Management routes added by a DHCP client display with Route Source as DHCP in the show ip management route
and show ip management-route dynamic command output.
● Management routes added by DHCP are automatically reinstalled if you configure a static IP route with the ip route
command that replaces a management route added by the DHCP client. If you remove the statically configured IP route
using the no ip route command, the management route is reinstalled. Manually delete management routes added by the
DHCP client.
● To reinstall management routes added by the DHCP client that is removed or replaced by the same statically configured
management routes, release the DHCP IP address and renew it on the management interface.
● Management routes added by the DHCP client have higher precedence over the same statically configured management
route. Static routes are not removed from the running configuration if a dynamically acquired management route added by
the DHCP client overwrites a static management route.
● Management routes added by the DHCP client are not added to the running configuration.
NOTE:
Management routes added by the DHCP client include the specific routes to reach a DHCP server in a different
subnet and the management route.
DHCP Client Operation with Other Features
A DHCP client also operates with the following software features.
Virtual Link Trunking (VLT)
A DHCP client is not supported on VLT interfaces.
VLAN and Port Channels
DHCP client configuration and behavior are the same on Virtual LAN (VLAN) and port-channel (LAG) interfaces as on a physical
interface.
Dynamic Host Configuration Protocol (DHCP)
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