Users Guide

• To display log messages for all DHCP packets sent and received on DHCP client interfaces, use the debug ip dhcp client
packets [interface type slot/port[/subport] command.
• To display log message on DHCP client interfaces for IP address acquisition, IP address release, IP address and lease time renewal, and
release an IP address, use the [no] debug ip dhcp client events [interface type slot/port[/subport]]
command.
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
The DHCP client operates with other Dell Networking OS features, as the following describes.
Stacking
The DHCP client daemon runs only on the master unit and handles all DHCP packet transactions. It periodically synchronizes the lease file
with the standby unit.
When a stack failover occurs, the new master requires the same DHCP server-assigned IP address on DHCP client interfaces. The new
master reinitiates a DHCP packet transaction by sending a DHCP discovery packet on nonbound interfaces.
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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