Filter
Top Products
DES-3500 Layer 2 Fast Ethernet Switch CLI Reference Manual
161
config dhcp_relay option_82 state
Purpose Used to configure the state of DHCP relay agent information option 82 of the
switch.
Syntax
config dhcp_relay option_82 state [enable | disable]
Description This command is used to configure the state of DHCP relay agent information
option 82 of the switch.
Parameters
enable - When this field is toggled to Enabled the relay agent will insert and
remove DHCP relay information (option 82 field) in messages between 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. When the DHCP server receives
the packet, 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. Then the DHCP server echoes 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 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 connects to the
DHCP client that sent the DHCP request.
disable - If the field is toggled to disable the relay agent will not insert and
remove DHCP relay information (option 82 field) in messages between DHCP
servers and clients, and the check and policy settings will have no effect.
Restrictions Only Administrator and Operator-level users can issue this command.
Example usage:
To configure DHCP relay option 82 state:
DES-3526:admin#config dhcp_relay option_82
state enable
Command: config dhcp_relay option_82 state
enable
Success.
DES-3526:admin#
config dhcp_relay option_82 check
Purpose Used to configure the checking mechanism of DHCP relay agent
information option 82 of the switch.
Syntax
config dhcp_relay option_82 check [enable | disable]
Description This command is used to configure the checking mechanism of
DHCP/BOOTP relay agent information option 82 of the switch.
Parameters
enable – 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.
disable - When the field is toggled to disable, the relay agent will not
check the validity of the packet’s option 82 field.
Restrictions Only Administrator and Operator-level users can issue this command.
Example usage:
To configure DHCP relay option 82 check: