D-Link DGS-3700 user manual Dhcp Relay Agent, Information Option, Check, Policy

	DGS-3700-12/DGS-3700-12G Series Layer 2 Gigabit Ethernet Switch User Manual
		DHCP relay information (option 82 field) in messages between DHCP servers and clients,
		and the check and policy settings will have no effect.
DHCP Relay Agent		This field can be toggled between Enabled and Disabled using the pull-down menu. It is
Information Option 82		used to enable or disable the Switches ability to check the validity of the packet’s option 82
Check		field.
		Enabled – When the field is toggled to Enable, the relay agent will check the validity of the
		packet’s option 82 field. If the switch receives a packet that contains the option-82 field from
		a DHCP client, the switch drops the packet because it is invalid. In packets received from
		DHCP servers, the relay agent will drop invalid messages.
		Disabled – When the field is toggled to Disabled, the relay agent will not check the validity
		of the packet’s option 82 field.
DHCP Relay Agent		This field can be toggled between Replace, Drop, and Keep by using the pull-down menu. It
Information Option 82		is used to set the Switches policy for handling packets when the DHCP Agent Information
Policy		Option 82 Check is set to Disabled. The default is Replace.
		Replace – The option 82 field will be replaced if the option 82 field already exists in the
		packet received from the DHCP client.
		Drop – The packet will be dropped if the option 82 field already exists in the packet received
		from the DHCP client.
		Keep – The option 82 field will be retained if the option 82 field already exists in the packet
		received from the DHCP client.
DHCP Relay Option		This function enables or disables the DHCP option 60 state. When option 60 is enabled, if
60 State		the packet does not have option 60, then the relay servers cannot be determined based on
		option 60. The relay servers will be determined based on either option 60 or per IPIF
		configured servers. If the relay servers are determined based on option 60, then the IPIF
		configured servers will be ignored. If the relay servers are not determined by option 60 then
		the IPIF configured servers will be used to determine the relay servers.
DHCP Relay Option		This function enables or disables the DHCP option 61 state. When option 61 is enabled, if
61 State		the packet does not have option 61, then the relay servers cannot be determined based on
		option 61. The relay servers will be determined based on option 61 and the IPIF configured
		servers will be ignored. If the relay servers are not determined either by option 60 or option
		61, then IPIF configured servers will be used to determine the relay servers.

Click Apply to implement any changes that have been made.

NOTE: If the Switch receives a packet that contains the option-82 field from a DHCP client and the information-checking feature is enabled, the switch drops the packet because it is invalid. However, in some instances, you might configure a client with the option-82 field. In this situation, you should disable the information-check feature so that the switch does not remove the option-82 field from the packet. You can configure the action that the switch takes when it receives a packet with existing option-82 information by configuring the DHCP Agent Information Option 82 Policy.

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