Zyxel VMG8823-B50B nat loopback by telnet

daniele

Goodmorning. Like in the title i need to set a nat loopback on the Zyxel VMG8823-B50B to access a local server using the external ip. In the web interface i have not seen that but may be through telnet it is possible. I am not so addicted to telnet....it is a stranger for me. I have opened a console and used this command  "ip nat loopback on" but this error message was done " object "nat" is unknow".
Some idea?
Tahnks.

#CPE_November