Hardening Linux Servers

In today’s computing world, the Linux operating systems or distros are beginning to have a fair amount of server market share. One reason behind that is because Linux has more flexibility, advanced features and is fast and secure.

Yes, Linux is already secured by default, but it’s only a basic level of security. Experienced hackers can easily break into a Linux web server that doesn’t have a hardened security or additional security software installed.

Every day, more and more hackers are starting to master and study loopholes and vulnerability on Linux servers, especially because they will continue to dominate the server market because of the rise of cloud computing. But worry not because Linux is developed with security in mind. You can also easily add software, firewall rules, SSH security and permissions to further lock down your Linux server’s security.

Securing Your Linux Web Server – Essentials

  • One of the most essential part of securing a Linux server is to make it physically secure. Add passwords to your BIOS and GRUB and disable booting from CD/DVD, External Devices, and Floppy Drive in BIOS.
  • Minimizing system packages is also a great way to eliminate security holes and vulnerability. If you have a service or software installed which is not regularly used, they can be left out and get outdated and it gives an open avenue for hackers to access your server. Remove unnecessary software, packaged and/or services to minimize threats.
  • Encrypting data communication is also an important part of your server security. Using FTP and the like can be easily intercepted by anyone in the same network using a packet sniffer. Using SSH, SFTP or RSYNC for file transfer is a secure way to transfer data to and from your server.
  • Using Linux security extensions can also improve your server security further. SELinux is one of the best security extensions for Linux that provides an “internal firewall system”.
  • Keeping your system updated is also a great way to minimize security vulnerabilities. Keeping your system up-to-date ensures that all vulnerabilities and security holes are patched to date.
  • Encouraging strong user passwords for user accounts also ensures that there will be no system breach or information leak. Applying password aging is also a good idea to keep passwords updated.
  • Disabling the root login is a must. You don’t need to login as a root to perform root level actions. Simply using sudo is enough.
  • Remove X Windows. This is an unnecessary software for a dedicated Linux server. Using the command line can greatly speed things up and allocate more resources for your server needs.


There are a lot of ways to make sure that your Linux server is safe from vulnerabilities and security holes. Sometimes, a simple common sense is necessary while there are times where expertise pays off.