Why I cannot remove the default interface?

Zyxel_James

Question: Why I cannot remove the default interface?

Answer:

For on-premises mode devices, only the model above 500 can remove the default interface, such as USGFLEX 500/700, ATP 500/700/800.
Please note that you must remove the reference settings to the default interface first.

For the Nebula mode firewall, all the models can remove the default interface. Of course, you have to remove the reference settings also.