Dhcp Relay; Introduction To Dhcp Relay Agent - 3Com Switch 4800G 24-Port Configuration Manual

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Introduction to DHCP
Relay Agent
Application
Environment
Fundamentals
DHCP R
When configuring the DHCP relay agent, go to these sections for information you
are interested in:
"Introduction to DHCP Relay Agent" on page 813
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"Configuration Task List" on page 815
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"Configuring the DHCP Relay Agent" on page 815
■
"Displaying and Maintaining DHCP Relay Agent Configuration" on page 819
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"DHCP Relay Agent Configuration Example" on page 820
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"Troubleshooting DHCP Relay Agent Configuration" on page 821
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n
The DHCP relay agent configuration is supported only VLAN interfaces.
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DHCP Snooping must be disabled on the DHCP relay agent.
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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. It 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 for ease of centralized management and cost reduction.
Figure 247 shows a typical application of the DHCP relay agent.
A
ELAY GENT
C
ONFIGURATION