Go to Management > Form Designer > Edit Form Edit form "sys - ISP Firewall:" and field "dienst_port" Set values Width (chars): 15 max. Length: 12 Regular Expression: /^[0-9]{1,5}[0-9]{1,5}|)$/ Save form. Now you can add a new firewall rule and set Port : min_port:max_port For exemple 20000:20100 open ports from 20000 to 20100