CentOS, Ubuntu, Debian three Linux comparison and similarities

Linux has a very large number of distributions, broken down in nature, and broadly divided into commercial versions maintained by commercial companies and free releases maintained by the open source community.

The commercial version is represented by Redhat, and the open source community version is represented by Debian. These editions have different characteristics and play different roles in different fields of application and cannot be generalize. The vast majority of VPS only offer release versions maintained by the open source community. Here's a simple analysis of these different Linux distributions.

Ubuntu

ubuntu more and more fans in recent years, Ubuntu has a beautiful user interface, perfect package management system, strong software source support, rich technical community, Ubuntu also has good compatibility with most hardware, including the latest graphics and so on. All this makes Ubuntu more and more popular in the direction of development. But don't forget:

Ubuntu's graphical interface is beautiful, but it also determines that its best application is the desktop operating system and not the server operating system. How do you want to have an immersive environment while learning Linux, then Ubuntu is good: it's only installed on your own computer and not on the server. From this point of view, Ubuntu does not have a list of operating system options installed on the VPS, and I believe you will not pay for the hundreds of M drive with valuable memory.

Centos

You will find that a lot of commercial companies deployed in the production environment are using the CentOS system, CentOS is a community re-release version compiled from Rhel source code. centos Simple, command line under the humanization of doing a better, stable, with strong English documentation and development community support. and Redhat have the same origin. Although commercial support is not provided separately, it is often possible to find a clue from the Redhat. Compared to Debian, CentOS is slightly larger. is a very mature Linux distribution.

Debian

Debian is generally more stable than Ubuntu, as a server-friendly operating system. It can be said that stability is unparalleled. The entire Debian system, as long as the application layer does not appear logical defects, basically impregnable, is a perennial system does not need to restart (of course, this is exaggerated points, but not exaggerated its stability). the entire system base of Debian is very small, not only stable, but also occupies little hard disk space and consumes less memory. a 128M VPS can run Debian smoothly, while CentOS is a little hard. However, due to the development of Debian, its help documents are slightly less than that of CentOS, and the technical data is less.

Because of its excellent performance and stability, Debian is very popular with VPS users.

In addition to the arch Linxu, Gentoo, Slackware and a series of Linux and FreeBSD, Unix and other systems, due to its field of more professional, rarely appear in the VPS, so do not introduce.

For starters, we recommend using CentOS or Debian, both of which can run smoothly on a low-profile VPS. However, Debian is recommended if the VPS configuration is too low (128M or less within the OpenVZ, or below 192M in the Xen architecture), otherwise it is recommended to use CentOS for more online help and support, making it easier for you to get started.

CentOS, Ubuntu, Debian Three Linux are very good system, open source system, also pay for the commercial version and free version, the following simple comparison of these three systems.

CentOS System

Many webmasters generally choose the CentOS system, CentOS is compiled from Redhat source code re-release version. CentOS removes many applications unrelated to server functionality, is simple but very stable, and command-line operations facilitate the management of systems and applications, as well as help documentation and community support.

Ubuntu system

Ubuntu has a bright user interface, complete package management system, strong software source support, rich technical community, and Ubuntu support for computer hardware better than CentOS and Debian, compatibility, Ubuntu application is very much, but for the server system, Personal feelings do not require much of a variety of applications, need to be stable, easy to operate and maintain a simple system. If you need to use the graphical interface on the server side, Ubuntu is a good choice, you need to be aware that the graphical interface occupies a very large amount of memory, and the larger the memory of the VPS price is also higher.

Debian system

Debian is also very suitable for server operating system, compared to Ubuntu, it does not have too much fancy, stability overwhelming, for the server system is a constant truth, Debian this Linux system, the bottom layer is very stable, the kernel and memory occupies very small, In small memory VPS can be run smoothly Debian, such as 128m of memory, but Debian's help documents and technical information is relatively small. For small memory, Debian is preferred, Debian is preferred for VPS masters who are very familiar with Linux systems.

In the system's choice, belongs to the novice, the preferred CentOS, is not CentOS is better than Debian and Ubuntu, but CentOS is the first choice for beginners to install VPS, it is stable, occupies less resources, the network can easily search the installation configuration of the document, its own Help document is very powerful , if you are a master of Linux, Master of the realm generally choose Debian, because the master can be in the low-provisioned VPS stable operation system, while Ubuntu, the system although free, but it is suitable for the rich to play, it occupies more resources than the previous two systems higher, and the VPS is basically selling memory, the higher the memory, The more expensive the price.

We are running some of the world's largest internet operations, so we attach great importance to reliability and stability as our first priority. To do this, we only use Linux to support our customers ' systems. But which Linux distribution should we use? The answer is, CentOS. Why is it?

As a large system operator, for a long time we need to find a reliable, predictable system in a wide variety of large systems, and we need strong support from the world's most powerful software vendors and open source projects. For those systems that are most commonly used, we need documentation, tools, and global resources.

That's why the Redhat/centos series release is our choice. They are able to meet all of the above requirements, and the problem is relatively small and long-term stable, which allows us to provide world-class maintenance for thousands of systems running different configurations, services and applications.

RedHat Enterprise Linux (RHEL) is the gold standard corporate distribution. It is updated every five years or so, and has a great advantage in system stability, foresight and security. Whenever a new major release, such as 5.x or the recent 6.x, all versions and code will remain unchanged, only security issues or major bugs, such as backdoor, port and other issues, will be released by the release of new sub-version to fix.

CentOS is the open source version of the Rhel release, which is usually released shortly after the release of Redhat. The reason we use CentOS is that the standard support services for Rhel distributions are very expensive, about $800 per server, which is a cost that must be controlled for many of our dozens of or even hundreds of servers.

The Rhel/centos system has two potential problems.

First, once the major version has been identified, other content will not be changed except for security and critical failures. While this is good for stability, it is bad for many services. MySQL and PHP services, for example, are heavily developed and extensively modified during the five-year Centos/rhel major release cycle. For example, MySQL5.0 is the version that is used by default for the current Rhel/centos major version, but currently MySQL has been updated to version 5.1 and 5.5.

Fortunately, this problem was easily solved by the Yum Package Manager. So far, the main software, such as the actual components of the current Rhel/centos, including the kernel and all the tools, still comes from the release, but those additional software such as Nginx,apache,php,java and MySQL, etc. from the updated software sources such as Fedora Or get the updated version directly from the developer such as MySQL. Here we have our own dedicated installation image to fully automate all of these things.

Second, The release of CentOS will lag behind the release of Redhat, including critical patches and fixes. This is particularly noticeable in the release cycle of Rhel 6.x. But according to our experience, there's nothing to worry about, and it's never going to be a problem for us.

Many people ask why we don't use Debian-based systems, such as Debian or Ubuntu servers. If there is no alternative, we will indeed support this proposal, but according to our experience, these systems are not as stable and reliable as rhel/centos.

We believe that this is due in part to the fact that they are developing too quickly and that there is less testing and immaturity between the various versions and combinations. Despite their popularity, however, major service providers and projects still prefer the rhel/centos system, as they can provide services to corporate customers (especially for Oracle and MySQL). In addition, Debian-based systems have many kernel and stability issues, especially in our cloud computing services.

For us, the only reason to use Debian/ubuntu is:

"They can provide the necessary special services for a system, especially when some drivers or some IO subsystems require a new kernel." For example, EXT4 file system or log changes in the nearest kernel, etc. now, all of this is contained in the rhel/centos6.x.

Of course, most Linux developers use Ubuntu's desktop version, and understandably, they are more inclined to use the same system when developing their production, and they can use a lot of interesting tools. But overall, we still believe that Rhel/centos is a better deployment platform and that more than 10 customers have successfully turned to CentOS as a production environment with no problems, but this is still a daunting task.