Differences between CentOS, Ubuntu, and Debian

Differences between CentOS, Ubuntu, and Debian
Article 1

Linux has many release versions, which are divided by nature into commercial versions maintained by commercial companies and free release versions maintained by open-source communities.

The commercial version is represented by Redhat, and the open-source community version is represented by debian. These versions have different characteristics and play different roles in different application fields. They cannot be generalized. The vast majority of VPS only provide release versions maintained by the open-source community. The following is a simple analysis of these different Linux distributions.

Ubuntu

Ubuntu has become more and more popular in recent years. Ubuntu has a beautiful user interface, a complete package management system, powerful software source support, and a wide range of technical communities. Ubuntu also has good compatibility with most hardware, including the latest graphics and graphics cards. All these have made Ubuntu more and more popular. But don't forget: All you need is a simple, stable, and easy-to-use server system!

The Ubuntu graphic interface is beautiful, but it also determines that its best application field is the desktop operating system rather than the server operating system. How do you want to have an immersive environment when learning Linux? Ubuntu is really good: Just install it on your computer, not on the server. From this point of view, Ubuntu does not select the operating system installed in VPS, and I believe you will not pay for the hundreds of MB driver and valuable memory.

CentOS

You will find that many commercial companies deploy their servers in the production environment to use the CentOS system. CentOS is re-released from the Community compiled by RHEL source code. CentOS is simple and user-friendly under the command line. It is stable and has powerful English documentation and support from the development community. It has the same origins as Redhat. Although business support is not provided separately, we can often find a clue from Redhat. Compared with debian, CentOS is slightly larger. Is a very mature Linux release.

Debian

In general, Debian, as an operating system suitable for servers, is much more stable than Ubuntu. It can be said that the stability is unparalleled. The entire debian system is a system that does not need to be restarted all the year round, as long as there are no logical defects in the application layer. (Of course, this is an exaggeration, but it does not exaggerate its stability ). The basic core of the entire debian system is very small, which is not only stable, but also occupies a small amount of hard disk space and memory. VPS of M can smoothly run Debian, while CentOS is slightly difficult. However, due to Debian's development path, Debian has fewer help documents than CentOS and fewer technical materials.

Due to its outstanding performance and stability, Debian is very popular with VPS users.

In addition, there are a series of Linux, FreeBSD, Unix, and other systems such as Arch Linxu, Gentoo, and Slackware, which are rarely used in VPS due to their more specialized fields.

For beginners, we recommend CentOS or Debian. Both systems can run smoothly on low-configuration VPS. However, if the VPS configuration is too low (there are less than MB in OPENVZ or less than MB in XEN architecture), Debian is recommended; otherwise CentOS is recommended, to get more online help and support, making it easier to get started.

Article 2

CentOS, Ubuntu, and Debian linux are all very good systems. Open-source systems are also divided into paid commercial and free versions. Below are a simple comparison of these three systems.

CentOS System

Many webmasters generally choose the centOS system. CentOS is compiled and re-released from the redhat source code. CentOS removes many applications that are not related to server functions. The system is simple but stable. command line operations can be used to facilitate management systems and applications, as well as help documentation and community support.

Ubuntu System

Ubuntu has a bright user interface, a complete package management system, powerful software source support, and a wide range of technical communities. In addition, Ubuntu provides better support for computer hardware than centos and debian, and has strong compatibility, ubuntu has a lot of applications, but for server systems, I feel that there is not much need for a variety of applications. What I need is stability, easy operation, and simple system maintenance. If you need to use the GUI on the server side, ubuntu is a good choice. You need to note that the GUI occupies a very large amount of memory, and the larger the memory, the higher the vps price.

Debian system

Debian is also very suitable for server operating systems. Compared with Ubuntu, debian does not have much fancy content. stability prevails over everything. It is a constant truth for server systems. Debian is a linux system, the underlying layer is very stable, and the kernel and memory usage are very small. In a VPS with small memory, Debian can run smoothly, such as MB of memory. However, debian has fewer help documents and technical materials. Debian is preferred for small memory and debian is preferred for vps masters who are very familiar with linux systems.

In terms of system selection, CentOS is the first choice for beginners. centos is not better than Debian and ubuntu, but centos is the first choice for beginners to install vps. It is stable and occupies less resources, you can easily find the installation and configuration documents on the network, and your help documents are also very powerful. If you are a linux expert, you generally choose debian as the best practice, because the master can run the system stably on the low-configuration vps, while ubuntu, although the system is free, is suitable for rich people to play, it occupies more resources than the previous two systems, vps basically sells memory. The higher the memory, the higher the price.

We are running some of the world's largest Internet operations. Therefore, we pay great attention to reliability and stability and are our top priority. Therefore, we only use Linux to support customers' systems. But which Linux release should we use? The answer is CentOS. Why?

As a huge system operator, for a long time, we need to find a reliable and predictable system among multiple large systems, we need strong support from the world's most powerful software vendors and open-source projects. For the most commonly used systems, we need documents, tools, and global resources.

For this reason, the RedHat/CentOS series release is our choice. They are able to meet all of the above requirements, with relatively few problems and long-term stability, which enables us to provide world-class maintenance for thousands of systems running different configurations, services and applications.

RedHat Enterprise Linux (RHEL) is a gold standard Enterprise release. It is updated every five years or so and has great advantages in system stability, foresight, and security. Every time a new primary version is released, such. x or the latest 6.x, all versions and codes will remain unchanged. Only security issues or major bugs, such as backdoors and ports, will be fixed by releasing a new sub-version.

CentOS is an open-source version corresponding to the RHEL release. It is usually released soon after the release of RedHat. The reason we use CentOS is that the cost of standard support services for the RHEL release is very high, about $800 per server. For many users who have dozens or even hundreds of servers, this is the cost that must be controlled.

The RHEL/CentOS system has two potential problems:

First, once the main version is determined, the content will not be changed except for the security issues and serious faults that will be repaired. Although this is good for stability, it is not good for many services. For example, for MySQL and PHP services, they will carry out heavy development and a lot of modifications during the CentOS/RHEL main version release cycle over the past five years. For example, MySQL5.0 is the default version of RHEL/CentOS, but MySQL has been updated to versions 5.1 and 5.5.

Fortunately, this problem was easily solved by the Yum Software Package Manager. Since then, the main software, such as the actual components in RHEL/CentOS, including the kernel and all tools, still comes from the release version, but the additional software, such as Nginx, Apache, PHP, Java, MySQL, and so on from updated software sources such as Fedora; or directly obtain the updated version such as MySQL from the developer. Here, we have our own dedicated installation image to fully handle all these tasks.

Second, CentOS release lags behind RedHat release, including key patches and fixes. This is particularly significant in the release cycle of RHEL 6.x. However, based on our experience, this is nothing to worry about, and it will never become a problem for us.

Many people ask why we don't need Debian-based systems, such as Debian or Ubuntu servers. If there is no choice, we will indeed support this suggestion, but based on our experience, these systems are not as stable and reliable as RHEL/CentOS.

We believe that, to some extent, this is caused by their rapid development and less mature tests between versions and combinations. Despite their popularity, the main service providers and projects still prefer RHEL/CentOS systems, because they can provide services to enterprise customers (especially for Oracle and MySQL ). In addition, Debian-based systems have many kernel and stability problems, especially in our cloud computing services.

For us,The only reason Debian/Ubuntu is:

"They can provide the necessary special services for a system, especially when some drivers or IO subsystems need a new kernel ". For example, ext4 file system or Log Changes in the recent kernel; now, all of this is included in RHEL/CentOS6.x.

Of course, most Linux developers use the Ubuntu Desktop version. It is understandable that they prefer to use the same system during development and production, you can also use many interesting tools. But in general, we still think that RHEL/CentOS is a better deployment platform, and more than a dozen customers have successfully switched to use CentOS as the production environment without any problems, however, this is still an arduous task.

In general, you will be more happy to see a well-managed CentOS system. We have thousands of servers using the CentOS platform, and only one server crashes on average every year. It is also hard to imagine that it is so rare, so pick an excellent, fast, and reliable platform!