Abstract: An method for expediting Virtual Local Area Network (VLAN) scanning for Dynamic Host Configuration Protocol (DHCP) server includes: transmitting, by a software tool, VLAN ethernet trunk frames including VLAN Identifier (ID) 1 to VLAN ID 4095, to an ethernet interface of a radio unit (RU), the ethernet interface being connected via an ethernet switch to a distributed unit (DU), wherein the DHCP server is located at the DU; selectively forwarding, by the ethernet switch to the DU, only a VLAN ethernet trunk frame having VLAN ID value X predefined by operator of the O-RAN system; selectively responding, by the DU, in response to receiving the VLAN ethernet trunk frame having VLAN ID value X, by sending a DHCP response message to the RU; and identifying, by the RU from the DHCP response message, the VLAN ID value X corresponding to the DHCP server.