DHCP relay agent configuration
Introduction to DHCP relay agent
Application environment
Since DHCP clients request IP addresses via broadcast messages, the DHCP server and clients must be on
the same subnet. Therefore, a DHCP server must be available on each subnet, which is not practical.
DHCP relay agent solves the problem. Via a relay agent, DHCP clients communicate with a DHCP server on
another subnet to obtain configuration parameters. Thus, DHCP clients on different subnets can contact the
same DHCP server, and centralized management and cost reduction are achieved.
Fundamentals
a
shows a typical application of the DHCP relay agent.
DHCP relay agent application
a.
DHCP client
DHCP client
No matter whether a relay agent exists or not, the DHCP server and client interact with each other in a
similar way (see the chapter
DHCP relay agent.
DHCP client
DHCP relay agent
DHCP client
"DHCP
overview"). The following describes the forwarding process on the
IP network
DHCP server
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