Over the years at Dedicated Server School, we have provided you with numerous security tips, often on an individual and specific level. This five-part series will instead give a general overview of Linux server security to serve as a quick reference tool whenever you might need it. Rather than searching for the security topic you need, you can find them linked in this guide.
OS Updates and System Checks
On the very surface, the number one thing you can do to secure your Linux server is to run OS updates. For Linux-based operating systems, this usually involves the use of a package management system to check, download, and install updates for the system kernel and any applications.
Linux distributions such as Red Hat Enterprise Linux, CentOS, Scientific Linux, and Fedora use a package management system called YUM for package installation and updates. You can perform manual updates or setup YUM to perform automatic updates.
Linux distributions such as Debian, Ubuntu, and others based on Debian use the APT package management system. With it you can both update packages and perform full system upgrades if desired.
Aside from updates, you can also perform basic security checks of your system to make sure everything is running smoothly. Linux includes many tools that allow you to do things like monitoring users or checking system logs.
In Part 2, we learn more about system logs and how to check them.