ConfigServer Security & Firewall (CSS) is an iptables based firewall for Linux systems. In our previous tutorial read installation tutorial of CSF on Linux system. CSF also provides in-built web UI for the managing firewall from the web interface. In this tutorial, you will find how to enable CSF Firewall Web UI on your system. Step 1 – Install Required Perl Modules: CSF UI required some of Perl modules to be installed on your system. Use the following commands to install required modules as per your operating system. Debian based systems: $ sudo apt-get install libio-socket-ssl-perl libcrypt-ssleay-perl \ libnet-libidn-perl libio-socket-inet6-perl libsocket6-perl Redhat based systems: $ sudo yum install perl-IO-Socket-SSL.noarch perl-Net-SSLeay perl-Net-LibIDN \ perl-IO-Socket-INET6 perl-Socket6 Step 2 – Enable CSF Firewall Web UI: To enable CSF web UI edit /etc/csf/csf.conf file in your favorite text editor and update the following values. $ sudo vim /etc/csf/csf.conf # 1 to enable, 0 to disable web ui UI = "1" # Set port for web UI. The default port is 6666, but # I change this to 1025 to easy access. Default port create some issue # with popular chrome and firefox browser (in my case) UI_PORT = "1025" # Leave blank to bind to all IP addresses on the server UI_IP = "" # Set username for authetnication UI_USER = "admin" # Set a strong password for authetnication UI_PASS = "admin" After making changes, edit /etc/csf/ui/ui.allow configuration file and add your public IP to allow access to CSF UI. Change OUR_PUBLIC_IP_ADDRESS with your public IP address. $ sudo echo "YOUR_PUBLIC_IP_ADDRESS" >> /etc/csf/ui/ui.allow Web…