D-Link xstack DGS-3612G Instruction Manual page 157

config dhcp_relay option_82 state
Parameters
Restrictions
Example usage:
To configure DHCP relay option 82 state:
config dhcp_relay option_82 check
Purpose
Syntax
Description
Parameters
Restrictions
Example usage:
To configure DHCP relay option 82 check:
xStack DGS-3612G Layer 3 Gigabit Ethernet Managed Switch CLI Manual
DHCP server and client. When the relay agent receives the DHCP
request, it adds the option 82 information, and the IP address of the
relay agent (if the relay agent is configured), to the packet. Once the
option 82 information has been added to the packet it is sent on to the
DHCP server, which receives the packet, and if the server is capable of
option 82, it can implement policies like restricting the number of IP
addresses that can be assigned to a single remote ID or circuit ID. The
DHCP server will then echo the option 82 field in the DHCP reply. The
DHCP server unicasts the reply to the back to the relay agent if the
request was relayed to the server by the relay agent. The Switch then
verifies that it originally inserted the option 82 data. Finally, the relay
agent removes the option 82 field and forwards the packet to the switch
port that is connected to the DHCP client that sent the DHCP request.
enable – Choose this parameter to enable the addition of option 82
information to a packet.
disable- Choose disable the relay agent from inserting and removing
DHCP relay information (option 82 field) in messages between DHCP
servers and clients, and the check and policy settings will have no
effect.
Only administrator-level users can issue this command.
DGS-3612G:4#config dhcp_relay option_82 state enable
Command: config dhcp_relay option_82 state enable
Success.
DGS-3612G:4#
Used to configure the checking mechanism of DHCP relay agent information
option 82 of the switch.
config dhcp_relay option_82 check [enable | disable]
This command is used to configure the checking mechanism of
DHCP/BOOTP relay agent information option 82 of the switch. 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.
enable – Choose this parameter to enable validity checking of option 82
within packets.
disable - When the field is toggled to disable, the relay agent will not check
the validity of the packet's option 82 field.
Only administrator-level users can issue this command.
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