The dhcp server option82 server-id-override enable command enables a DHCP server to fill the Option 82 suboption Server Identifier Override in Option 54.
The undo dhcp server option82 server-id-override enable command disables a DHCP server from filling the Option 82 suboption Server Identifier Override in Option 54.
By default, a DHCP server fills its IP address instead of the Option 82 suboption Server Identifier Override in Option 54.
Usage Scenario
In an inter-VPN unicast address lease renewal scenario, to enable a DHCP server to fill the Option 82 suboption Server Identifier Override in Option 54, run the dhcp server option82 server-id-override enable command. This suboption contains the DHCP relay interface IP address. After receiving a response packet from the DHCP server, a DHCP client uses the DHCP relay interface IP address as the destination address of lease renewal packets. This ensures that lease renewal packets can still be sent to the DHCP relay agent for inter-VPN forwarding.
Configuration Impact
After this command is run, the DHCP client cannot directly detect the IP address of the DHCP server.
Precautions
If the dhcp server option82 server-id-override enable, server identifier ip, and dhcp server identifier dest-ip commands (listed in decreasing order of preference) are all configured, only the dhcp server option82 server-id-override enable command takes effect.