Why can't the SFP LAN interface assign a DHCP IP normally?

Zyxel_Jeff

Question:

The user may face an issue where the SFP interface is set as an internal LAN zone port, but it fails to assign a DHCP IP to the host client. What could be the possible reason, and how can this problem be resolved?

Answer:

The possible reason why the SFP interface fails to assign a DHCP IP to the host client is the missing DHCP server settings on the SFP interface. Please enable the DHCP server settings to resolve this issue, as shown below:

Verification Result:

If the host client connects to a switch that is connected to the SFP port of the Zyxel firewall, it will receive a DHCP IP in the range of 192.168.66.X from the DHCP server normally, as shown below: