Hello there!
By default, the interface works in the Layer 2 mode. STP is enabled on the device. However, the interface connected to the terminal is not enabled with the STP edge port function. The port has to wait for two forwarding delays to enter the
FORWARDING mode. During this period, the DHCP request packet sent by the terminal NIC is not received by the AR.
After the edge port function has been enabled on the interface connected to the terminal, it enters the forwarding state immediately when the port is powered on and the terminal can obtain the address quickly.