Previously we talked about the differences between VPS and cloud servers. In this post, let’s take a look at the operating systems used on servers!
When purchasing a VPS, cloud server, or physical machine, we always need to select an operating system before proceeding.
The difference is that with VPS and cloud servers, we can reinstall or switch to a different system for free multiple times after purchase. For physical servers, however, some require manual operation to reinstall the system (though some offer automatic installation), which is relatively more cumbersome. Some providers even limit the number of free installations, for example, only allowing 2-3 free installs per billing cycle, with additional reinstalls incurring a fee, while others may charge under the name of a “setup fee.”
Unlike the Windows and macOS systems we commonly use daily, in the server space, free and open-source Linux systems dominate, holding over 80% market share. This type of system does not require expensive licensing fees. The remaining share belongs to systems like Windows and Unix. Because Linux is open-source, it can be freely modified and distributed, leading to many different distributions, such as CentOS, Debian, Ubuntu, and so on. Below, we’ll briefly introduce these popular Linux distributions, hoping to provide a reference when you make your choice.
CentOS, Red Hat:
The reason we group these two together is that many people see CentOS as an open-source implementation of the famous commercial operating system Red Hat Enterprise Linux. In fact, whether it’s the intricate connections between them or the system commands, they are almost identical. Once you learn one, you can easily pick up the other. Their stability has also been proven by the market. They have a high market share and the lowest operational costs. The system is quite universal, with a huge user base, especially domestically in China. Whether you’re hosting a regular website, a database, or using it for special networking purposes, it’s highly suitable, offering good stability, reliability, and the lowest maintenance costs.
Particularly in China, many companies and individuals use this system. Its technical documentation is comprehensive, and most problems can be easily solved by searching online. It’s a relatively balanced system, performing moderately well in all aspects.
Debian:
Personally, I consider this the most stable and secure system. To sum it up with a saying from a netizen, “As long as nothing goes wrong at the application level, the system is almost impregnable.”
Additionally, because its core is very small and it is so stable (steady as an old dog), many other systems are based on it for secondary releases. For example, the mobile Linux operating system (AidLux) we mentioned in a previous video, many IoT systems, and Ubuntu, which we’ll discuss later, are all developed based on it.
If you have limited memory, like only 512MB, this system is very suitable for you; it runs well without needing too many resources.
Although some packages in it are not updated very promptly, it also has the fewest bugs and is the most stable. It’s a purer system better suited for servers, and those who like it, like it a lot. Currently, one of my personal websites uses this system, and I’m very likely to switch to Debian in the future (currently mainly using CentOS).
The downside is that it’s not as beginner-friendly as CentOS. Sometimes a strength is also a weakness; Debian is relatively conservative, prioritizing stability over newness in software updates. Unlike the CentOS just mentioned, Debian’s popularity domestically is far lower than it is overseas. The number of technical documents is moderate, so users who like to tinker might skip this system. I personally feel this system is not very suitable for novice users (especially domestic users). If you want to use this family of systems, you can start practicing with Ubuntu first. Ubuntu’s update strategy is more aggressive, making the integration and installation of many software packages more convenient, and the packages in its repositories are newer than Debian’s.
Ubuntu 
Built upon Debian, this distribution shares many of the same commands and uses the same package manager. Learning one greatly helps with the other. This system emerged relatively later, but its user base has been growing more and more in recent years. Compared to the two systems above, it has a flashier interface, newer software packages, and is more user-friendly for the average person. It currently has multiple versions, including a desktop edition and a server edition.
Many optimizations and adaptations have been made for enterprises. For companies working on cloud servers and storage functions, it’s a very suitable system. In practice, I’ve personally encountered many professional services dealing with storage (like Ceph storage) and cloud server platforms (like OpenStack) that mostly use this system. It natively integrates many features, offering ready-made functions that can save a lot of development work. Moreover, there are tons of tutorials and documents online for this, making problem-solving very convenient. However, this convenience can sometimes come at the cost of stability, which certainly can’t compare with Debian. While development is convenient, more modifications inevitably introduce problems. Whether it’s the system’s own update strategy or the development done on it, inexplicable minor bugs are unavoidable.
This is both a strength and a weakness; everyone can find a balance between portability and stability based on their own situation.
The above are the three most mainstream Linux distribution systems, which almost all hosting providers offer for free, regardless of whether you purchase a server domestically or abroad.
Besides these systems, there are many other distributions, such as Fedora, which is also popular and has intricate connections to the Red Hat system, along with other mainstream distributions.
Of course, there are also many relatively niche distributions that aren’t commonly used on servers but are very practical in specific offline fields, such as systems specifically designed for penetration testing (Kali) and systems focused on privacy (Tails). They each have their own specialties in their respective domains.
For ordinary users who haven’t had much contact with Linux systems, I personally suggest choosing between CentOS or Ubuntu. Both have a very large user base and extensive problem-solving documentation. If any problem arises, just searching online usually allows you to solve it yourself.
For those with special requirements:
If you want rapid development