dhcp option82 vendor-specific insert enable

Function

The dhcp option82 vendor-specific insert enable command enables a DHCP relay-enabled gateway to insert the Vendor-Specific suboption (suboption 9) of Option 82 into a DHCP packet.

The undo dhcp option82 vendor-specific insert enable command disables a DHCP relay-enabled gateway from inserting the Vendor-Specific suboption (suboption 9) of Option 82 into a DHCP packet.

By default, the Vendor-Specific suboption (suboption 9) of Option 82 is not inserted into a DHCP packet.

Format

dhcp option82 vendor-specific insert enable

undo dhcp option82 vendor-specific insert enable

Parameters

None

Views

Global VE sub-interface view, VBDIF interface view, VE sub-interface view

Default Level

2: Configuration level

Task Name and Operations

Task Name	Operations
dhcp	write

Usage Guidelines

Usage Scenario

In·EVPN·active-active·scenarios,·DHCP·users·obtain·IP·addresses·from·DHCP·servers·in·different·subnets·through·DHCP·relay-enabled·gateways.·Users·in·a·subnet·use·the·same·gateway·address.·If·the·gateway·address·is·carried·as·the·destination·IP·address·in·a·response·packet·from·the·DHCP·server,·the·packet·may·not·be·sent·to·the·gateway·of·the·user.·As·a·result,·the·user·fails·to·go·online.·To·resolve·this·problem,·run·the·dhcp·option82·vendor-specific·insert·enable·command·to·enable·a·DHCP·relay-enabled·gateway·to·insert·the·Vendor-Specific·suboption·(suboption·9)·of·Option·82·into·a·DHCP·packet.·Then,·run·the·dhcp·option82·vendor-specific·format·command·to·configure·a·format·for·the·Option·82·suboption·9·and·encapsulate·the·IP·address·that·uniquely·identifies·the·gateway·location·into·a·DHCP·request·packet·to·be·sent·to·the·DHCP·server.·The·DHCP·server·that·supports·the·Option·82·reserves·this·suboption·in·the·response·packet.·If·the·response·packet·is·sent·to·a·wrong·gateway,·the·DHCP·relay-enabled·gateway·forwards·the·packet·to·the·correct·gateway·based·on·the·IP·address·carried·in·the·suboption·9.

Follow-up Procedure

Run the dhcp option82 vendor-specific format command to configure a format for the Option 82 suboption 9.

Example

# Enable a DHCP relay-enabled gateway to insert the Option 82 suboption 9 into a DHCP packet.

<HUAWEI> system-view
[~HUAWEI] bridge-domain 10
[*HUAWEI-bd10] quit
[*HUAWEI] interface vbdif 10
[*HUAWEI-Vbdif10] dhcp option82 vendor-specific insert enable