Question

Is there a way to temporarily disable the WIFI access point of RUT240 without going through the WebUI? (e.g. with a special command via the LAN port)

Answer 1

Use UCI to do it from the command prompt or programatically, this will do interface 1 but you can add more for interface 2 etc.

#disable 

                        uci set wireless.@wifi-iface[1].user_enable=0 
                        uci set wireless.@wifi-iface[1].disabled=1
 

 # enable
                        uci set wireless.@wifi-iface[1].user_enable=1 
                        uci delete wireless.@wifi-iface[1].disabled