Uncomplicated Firewall Install a very simple and uncomplicated forewall that is designed for Linux and works perfectly for Ubuntu. sudo apt-get install ufw gufw UFW is command line but very simple tool to manage your firewall however you can also use GUFW in gui format or within X Windows for a user friendly graphical interface. Block too many ssh or brute force attacks Install DenyHosts sudo apt-get install denyhosts Usually it protects your ssh services automatically and can send emails with reports however further configuration can be made in /etc/denyhosts.conf
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