Displaying And Maintaining The Dhcp Relay Agent - HPE FlexNetwork HSR6800 Configuration Manual

information, but the secondary gateway cannot. The secondary gateway can only forward DHCP
replies to all PWs.
To enable the secondary gateway to forward a DHCP reply to only the intended PW, perform the
following tasks:
•
Configure the dhcp relay information enable and dhcp relay information circuit-id (with
sub-interface-vlan specified) commands on the primary gateway. Then, when the primary
gateway receives a DHCP request, it adds Option 82 to the reply and record the VLAN ID of the
L2VE subinterface.
•
Configure the dhcp relay information enable, dhcp relay information circuit-id (with
sub-interface-vlan specified), and dhcp relay forward reply by-option82 commands on the
secondary gateway. Then, when the secondary gateway receives a DHCP reply, it resolves
Option 82, records the VLAN ID of the L2VE subinterface, and forwards the reply to the PW.
To configure the DHCP relay agent to forward DHCP replies based on Option 82:
Step
1. Enter system view.
2. Enter interface view.
3. Enable the relay agent
to handle Option 82.
4. Configure the padding
mode and padding
format for the Circuit ID
sub-option.
5. Configure the DHCP
relay agent to forward
DHCP replies based on
Option 82.

Displaying and maintaining the DHCP relay agent

Execute display commands in any view and reset commands in user view.
Task
Display information about DHCP servers on an
interface.
Display Option 82 configuration information on the
DHCP relay agent.
Command
system-view
interface interface-type interface-number
dhcp relay information enable
dhcp relay information circuit-id { bas
[ sub-interface-vlan ] | string circuit-id |
{ normal | verbose [ node-identifier
{ mac | sysname | user-defined
node-identifier } ] [ interface ] }
[ sub-interface-vlan ] [ format { ascii |
hex } ] }
dhcp relay forward reply by-option82
Command
display dhcp relay server-address [ interface
interface-type interface-number ]
display dhcp relay information [ interface
interface-type interface-number ]
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Remarks
N/A
N/A
By default, handling of Option
82 is disabled.
By default, the padding mode
for the Circuit ID sub-option is
normal, and the padding
format is hex.
The device name (set by using
the sysname command) must
not include spaces if it is
configured as the padding
content for sub-option 1.
Otherwise, the DHCP relay
agent will fail to add or replace
Option 82.
You must set the padding
mode to bas, normal, or
verbose, and specify the
sub-interface-vlan keyword
for this command.
By default, the DHCP relay
agent does not forward DHCP
replies based on Option 82.