If you are planning on creating a website hosted on a virtual private server, then you’re probably thinking that a Linux server is secured out of the box. For an average user, the default configuration of Linux is good, but if you are going to use it to host a website, then you are opening your server to a lot of risk which can’t be prevented or fought by a default Linux installation. With that in mind, let’s take a look at some of the tips for hardening your Linux servers to prevent hackers from gaining access to your server.
Encrypt Data Communication
All data transmitted over a network can be monitored. Therefore, you must ensure that your data communications are encrypted. If possible, try to encrypt transmitted data using passwords or using keys/certificates. If you are an avid user of FTP, use SFTP instead. It’s similar to FTP instead that all transfers are encrypted, so there will be no clear text passwords exposed to the world.
Install Security Patches
Installing security patches is important when it comes to maintaining a server. Upgrading software and system applications is crucial to make sure that bugs, vulnerabilities and other security related concerns can be prevented.
This is usually a no-brainer since this is the first layer of protection that we have in this day and age. Therefore, make sure you use proper passwords, those which aren’t easily guessed and used every day. Strong passwords make it harder for crackers to penetrate your server.
Bind Processes on Localhost
Not all daemon needs to be accessible over the network. One example of that scenario is a database such as MySQL. There is no need for it to be accessible via network so bind this process to localhost or 127.0.0.1 to prevent any malicious breaking attempts.
Minimizing packages will also minimize your vulnerability. Consider removing any packages that you think is unnecessary for your daily operation. Find services running on runlevel 3 using the chkconfig command to find and remove unwanted services.
Secure Your Physical System
Securing your physical system might not be in your high priority list but physically securing your server is a very important part of making your Linux server as secure as possible. Configure the BIOS to prompt for a password and also the same for the GRUB. Disable booting from CD, DVD, External Devices and Floppy Drives if possible.
Another no-brainer is firewall implementation. This is a crucial part to make sure that malicious traffic can be blocked even before entering your web server.