User's Manual

UTT Technologies Chapter 7 Advanced Setup
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message, it will process message according to the settings of these two parameters, see
the following table for detailed description:
Option Policy
The message is from another relay
agent, and already contains option 82.
The message is from a client directly,
and doesn¶t contain option 82.
insert
drop Drop the message.
The relay agent will insert option 82 into
the message before forwarding it.
keep
The relay agent will retain the existing
option 82 in the message and forward it.
replace
The relay agent will replace (overwrite)
the existing option 82 with its option 82 in
the message before forwarding it.
disabled
drop Drop the message.
Forward directly.
keep Forward directly.
replace Forward directly.
Table 7-3 DHCP Relay Agent Forwarding Policies
The following explains the meanings of the parameters in the above table.
Option 82: It indicates the relay agent information option.
Option: It is used to enable or disable the Device to insert option 82 before forwarding a
client-originated DHCP message that doesn¶t contain option 82. By default, the relay
agent will forward the message directly. If you want to insert option 82 into the message
before forwarding it, please select insert. Note that, when the Option is set to disabled,
the DHCP relay agent will drop or forward the message directly.
Policy: It is used to configure the reforwarding policy for a DHCP relay agent (what a relay
agent should do if a message already contains option 82). A DHCP relay agent may
receive a message from another relay agent that already contains relay information. By
default, the relay agent will retain the existing option 82 in the message and forward it. If
this behavior is not suitable for your network, you can set Policy to change it.
7.8.2.4 Introduction to Raw Option
DHCP provides a framework for passing configuration information to hosts on a TCP/IP
network. Configuration parameters and other control information are carried in tagged