CentOS

Everything You Want to Know About CentOS as Linux Distribution

What is CentOS?

Community Enterprise Operating system (CentOS) offers an open-source, enterprise-class free operating system that is practicably compatible with Red Hat Enterprise Linux (RHEL). “Gregory Kurtzer” is the founder of CentOS. CentOS developers use the RHEL source code to generate a product that is highly comparable to RHEL.

CentOS provides a development platform in one of the best and most powerful available distributions. It is a community-driven free software project built to provide a robust platform for the open source communities to grow. It is highly adaptable, as well as safe and strong. In addition, it features several corporate-level security updates that declare it an excellent choice for any use.

In this article, we are going to cover the following 16 points related to CentOS as a Linux Distribution:

  1. History of CentOS
  2. Aim of CentOS development
  3. CentOS and RHEL
  4. Special Interest Groups (SIGs)
  5. What is the CentOS project?
  6. What is CentOS good for?
  7. CentOS Architecture
  8. Repositories
  9. CentOS main features
  10. Advantages of CentOS
  11. Hardware requirements for CentOS latest versions
  12. CentOS latest releases
  13. CentOS End of Support (EOS) Schedule
  14. Most valuable commands in CentOS
  15. Why IT leaders love CentOS?
  16. How will CentOS play its role in your career growth?

History of CentOS:

CentOS was released in May 2004 as an operating system that is completely free and based on the Linux kernel. CentOS is originated from RHEL. Its goal is to deliver an enterprise-class computing platform that is freely available and maintain Red Hat’s binary compatibility. CentOS was introduced as a CAOS build and was founded by “Gregory Kurtzer.”

After that, “David Parsley,” Tao Linux primary developer, announced in June 2006 that Tao Linux would be retired and its development would be absorbed into CentOS (Tao Linux is another RHEL clone). By using the yum update, Tao users were able to upgrade their current system version to CentOS. Unfortunately, “Lance Davi,” the founder of CentOS, was reported missing on the CentOS project website in July 2009. “Davis” had stopped contributing to the CentOS project, but he had kept his CentOS website.

The CentOS team allegedly contacted “Davis” in August 2009 and got the domains of centos.org and centos.info. CentOS became the most popular Linux distribution in July 2010 and overtook Debian’s popularity for web servers, accounting for over 30% of all Linux web servers. However, in January 2012, it was dropped to second place by Debian. Red Hat declares in January 2014 that the team will sponsor the CentOS project, assisting in the development of a platform that is compatible according to the requirements of the open-source developers that work around the operating system and emerging technologies.

CentOS trademarks have been shifted to Red Hat. RHEL standards and open-source team group, which work independently from the RHEL team, employs the CentOS lead developers. In the hosting market, CentOS is considered the most reliable distribution. CentOS is exceptionally compatible with most Linux software because of its binary compatibility with RHEL. CentOS is also the most suitable Linux distro for most hosting control panels.

Aim of CentOS development:

CentOS development aims to provide a robust system for open source communities for development purposes. In addition, this platform can be used for scientific data processing and hosting businesses; for example, Companies can use this dependable platform to host their programs.

RHEL and CentOS:

CentOS is a commercial Linux distribution based on the RHEL source code and is supported by the community. Because Red Hat builds their product using open source software, that’s the reason they have to make their source code public. Subsequently, CentOS and RHEL are functionally equivalent, with the main differences being the removal of vendor artwork and branding.

On the other hand, CentOS lacks Red Hat certifications because it is based only on its source code. The CentOS project uses the Red Hat publicly available source packages to produce binary packages, which anybody can use for free. Still, specific updates are not made public; there may exist some variations between the packages delivered by CentOS and Red Hat.

Red Hat has supported the CentOS project since 2014 to assist open source developers in developing a suitable platform that utilizes CentOS to integrate technologies. In the same year, CentOS and Red Hat developers formed the Governing Board, which various working groups now supervise. This Governing Board is made up of CentOS project founders as well as Red Hat employees.

Special Interest Groups (SIGs):

Special Interest Groups (SIGs) are the teams in which specific members of the CentOS community are concerned about raising awareness, boosting up the Linux distribution, and improving functional aspects such as documentation and infrastructure. Virtualization, ArtWork, and Core are some of the active special interest groups.

What is the CentOS project?

This Project comprises a group that is responsible for the maintenance of the CentOS development framework. It operates more than an operating system and issues resources to help other organizations develop CentOS-based technologies. Furthermore, this project aspires to make CentOS Linux a premier community platform for developing new open source technologies from other projects.

What is CentOS suitable for?

This Linux version is suitable for business users who do not want to pay the high fees associated with RHEL. These two distributions are identical for a given version save for RHEL subscription management and RHEL branding and are frequently referred to as “Enterprise Linux.”

CentOS Architecture:

CentOS has somehow similar architecture as compared to other Linux distros. However, it only supports the x86-64 architecture. This statement declares that it can run in both 64-bit and 32-bit platforms:

  • The physical or hardware equipment, such as network devices, storage, and computer systems, is at the bottom.
  • The kernel, the Operating System fundamental component that interacts directly with the hardware, lies on top of this.
  • The shell sits on top of the kernel and serves as an interface between the kernel and the user.
  • The application layer exists at the top of all of these levels, interacting with the kernel and shell to perform user-specified activities. Media players, Web browsers, text editors, file explorers, etc., are examples of applications.

Repositories:

The main CentOS distribution is made up of three primary repositories, which are also known as channels, each of which contains these software packages:

  • Updates include packages delivered between the regular update sets for point releases and enhancement updates, bugfix, or security. Only enhancement updates and bugfix that aren’t eligible for publication through the CentOS-Fasttrack repository are provided in this manner.
  • base: includes packages that make up CentOS point releases and are updated when the point release is formally released as ISO images.
  • addons: offers packages needed to construct the packages that make up the standard CentOS distribution but aren’t offered by the upstream.

The CentOS Project maintains many additional repositories that comprise software packages not found in update repositories and default base. The following are some of the repositories:

  • CentOSPlus: includes packages that update specific base CentOS components, causing CentOS to differ from the content provided by the upstream source.
  • CentOS-Fasttrack: includes enhancement updates and bugfix released regularly in-between point release update sets. Packages released in this manner are considered strong candidates for inclusion in the next point release. Therefore, the CentOS-Fasttrack repository does not contain unsuitable packages for inclusion in point releases. Moreover, it also does not provide any security updates.
  • debuginfo: when the central packages are built, this repository stores packages that have generated debugging symbols.
  • Software Collections: Provides newer versions of software than the standard distribution.
  • CentOS Extras: it is a collection of packages that add functionality to CentOS without compromising upstream compatibility or requiring the base components to be updated.
  • contrib: This repository supply those packages that do not lap over with any of the packages found in the core distribution.
  • Continuous Release (CR): makes packages that will appear in CentOS next point release broadly available. Until the actual point release is actually released in ISO images, the packages are accessible for hot fixing and testing.
  • CentOS-Testing: This repository serves as a testing area for packages destined for CentOSPlus and CentOS Extras. This repository’s packages may or may not replace CentOS distribution core packages, and their functionality is not assured.

CentOS main features

RHEL and CentOS share many features because CentOS is based on the source code of RHEL.

High performance & availability:

It uses a Kernel-based Virtual Machine for virtualization and provides high availability and excellent performance.

Stable Linux distribution:

CentOS is supported by a dedicated developer community that maintains it up to date and ensures compatibility with both and new software. Furthermore, core developers are backed up by a global community of volunteer users such as Linux enthusiasts, network administrators, system administrators, and so on, who test releases, manage updates, and offer help in the development.

Regular updates and support:

CentOS versions are updated every six months on average, and each release is supported for ten years.

High level of security:

The security team at Red Hat is provident in detecting threats and ensuring a high level of security. CentOS also comes with the Security-Enhanced Linux kernel extension.

When it comes to specifications, like any other Linux system, CentOS has a lot to offer. The CentOS in-house documentation covers many finer points; most programmers should familiarize themselves with the big picture before deciding on a CentOS dedicated server. Before you try CentOS for yourself, here’s a look at all you need to know about it.

CentOS is not RHEL:

RHEL has been repackaged as CentOS. Whereas, CentOS team is a volunteer group that packages the RHEL source packages into publicly available binaries. After then, the software is distributed via several public mirrors. Red Hat and CentOS do not have a direct link or partnership, as far as I am aware. In the past, the lack of formal partnerships had caused issues, such as when Red Hat insisted that from CentOS, all the Red Hat branding should be removed.

Many organizations provide support for CentOS Linux, but still, there is no proper commercial support available. Red Hat provides direct support with RHEL. For commercial CentOS support, a CentOS user depends on IT experts and the community.

Many top-tier specifications are included in CentOS:

CentOS consists of a large number of unique specifications that permit more innovation inside this platform. CentOS 6 and 7 are based on the Linux 2.6.32 and Linux 3.10.0 kernels, respectively. These distros are “plug and play” nature-wise, supporting mp3 files from different sources and Firefox 60 as the default internet browser.

The x86_64 architecture in CentOS 6 and 7 can allocate 12 and 64 TB space in terms of CPU capability. In the meantime, the local file system can handle maximum file sizes ranging from 2 TB to 100 TB in different configurations. CentOS also makes it possible to add a range of helpful features. For instance, the current versions of CentOS support native Bluetooth as well as Security-Enhanced Linux.

CentOS has the capability to supports x86_64 and x86 Architecture:

Currently, this Linux distribution support both x86_64 and x86 systems. However, CentOS 7 is unique because it presently helps unofficial, community-maintained ppc64, ppc64le, Arm32, i686, and Arm64 architectures. Whereas CentOS 6 can support both architectures.

You can download CentOS for free:

CentOS is a freely available distro to distribute and to use. CentOS invites people to tamper with it and find new ways to increase functionality within the Linux distribution because of its community-driven development model. CentOS offers various options for downloading their software, including Minimal ISO, Amazon Web Services, torrent, DVD ISO, and more. At the same time, CentOS source packages are available through their file vault and are not incorporated in ordinary downloads.

CentOS Community is Growing:

CentOS community has committed to developing it patch by patch, which is one of the critical reasons it controls maintaining a significant market share. This open society has come together through time and developed individual SIGs. These organizations are much concerned with enhancing specific functional areas such as virtualization and user experience.

CentOS Governing Board chooses which SIGs can start work under their protection. Any community member can play their part in a SIG until they can accept community criticism and have sufficient documentation. Then the community is also settled to help both experienced users and newbies. As a result, they offer various mailing lists to assist users in getting direct advice from other community members, available in different languages.

CentOS provides manuals to the users:

The CentOS Project necessitates new users to make the most of every moment of work they’ve put in so far. For that, they’ve created a library of documentation to help them get started. This library contains a step-by-step installation guide for various architectures and releases notes for major modifications.

To quickly overview the features of CentOS, check out the table given below:

Features CentOS
System core CentOS is based on RedHat
Package management YUM
Update Cycle Less frequent
Hosting Market Share 17.5% of Linux users
Virtualization OpenNebula

OpenStack, CloudStack,

Security Strong
Stability Strong
Default applications Applications are updated when required
Maintenance Challenging
Support Solid documentation with a small but active community
Ease of Use Challenging
Speed Excellent but hardware-dependent
File Structure same basic file/folder structure, but the format differ in system services location

Advantages of CentOS:

Here are some of the benefits of utilizing it:

  • It is fast, dependable, and lightweight.
  • It is freely available, open-source, and enterprise-ready.
  • In addition, you’ll get version control tools like git, which are all pre-installed, also open-source server software like MySQL, CUPS, Apache Web.
  • It also provides excellent community support, including the ability to submit bugs directly to bugs.centos.org.
  • The most recent CentOS version incorporates virtualization technology and hypervisor such as Xen, oVirt, and Docker.
  • CentOS distro provides the same features as the commercial RHEL. However, this is also accessible at no cost!
  • Compared to other freely available, open-source Linux distributions, CentOS is widely favoredbecause of its reliability and fewer package upgrades.

Hardware requirements for CentOS latest versions:

Linux distro Processor RAM Disk space System architecture
CentOS 8 1.1 GHz Minimum storage: 1 GB

Recommended storage: 2 GB

Minimum: 20 GB

Recommended: 40 GB

64-bit
CentOS 7 or RHEL 7 1.1 GHz Minimum Storage: 1 GB

Recommended Storage: 2 GB

Minimum: 20 GB

Recommended: 40 GB

64-bit

CentOS latest releases:

We have CentOS 7, CentOS 8, and CentOS Stream to talk about CentOS’s latest releases. In 2019, when CentOS 8 was introduced, many people wondered what had changed significantly from CentOS 7. Now, we will figure out the contrast between these two CentOS versions. So, let’s get to the bottom of this mystery and check out if CentOS 8 is worthy of trying out or not.

CentOS 7 was the first RHEL distribution to include “systemd” as a standard feature. CentOS 7 was released in 2014 and offered several features that have assisted the community well over the past ten years. Other new features in CentOS 8 are shown in the table below, along with some of the differences between the two CentOS releases:

Difference between CentOS 7 and CentOS 8

Features CentOS 7 CentOS 8
Git Git version 1.8 Git version 2.18
Containers Docker is available for CentOS 7 Docker is omitted. For work with containers, utilize the  skopeo, and buildah, podman,  runc tools.
Kernel Based on upstream kernel 3.10 and Fedora 19 Based on upstream kernel 4.18 and Fedora 28
Storage Management Logical Volume Manager default Logical Volume Manager and Stratis
Security CentOS 7 includes support for TLS 1.0 and OpenSSL 1.0.1 CentOS 8 includes support for TLS 1.3, OpenSSL 1.1.1, TLS 1.0 and TLS 1
NTP Both chronyd and NTP daemon available Only chrony NTP protocol
Software Management It used YUM v3, distributed with RPM 4.11 In CentOS 8, yum is replaced with dnf. It also utilizes the combination of RPM 4.14 YUM v4. Moreover, this version also supports modular content.
Java OpenJDK 8 Both OpenJDK 8 and OpenJDK 11
Networking Framework This version uses iptables CentOS 8 networking framework is based on nftables which firewalld utilizes for the default backend.
Python support limited support for Python 2.7. CentOS 7 also supports Python 2.7 fixed support for Python 2.7, but it also supports Python 3.6
Virtualization Utilize virt-manager and qemu-kvm Distributed with virt-manager, qemu-kvm 2.12 deprecated, and Cockpit taking over
httpd/Apache HTTP Server 2.4 HTTP Server 2.4
Firewall CentOS 7 utilize iptables as its  filtering framework for packets CentOS 8 utilize nftables as its filtering framework for packets
ruby, php,perl Ruby 2.0.0, PHP 5.4.16, Perl 5.16.3 Perl 5.26, Ruby 2.5. Whereas,  by default, FastCGI Process Manager (FPM) is utilized by PHP.
Databases MySQL 5.5, PostgreSQL 9.2,  MariaDB 5.5 MySQL 8.0,  PostgreSQL 10, Redis 5, PostgreSQL 9.6, MariaDB 10.3
Desktop Environment In CentOS 7, the X.Org server is the default GNOME, display manager. In CentOS 8, Wayland is the Default GNOME Display Manager with GNOME Shell version 3.28
Nginx not available (by default) This Linux distro provides support for the Nginx web server. Version 1.14

With the CentOS 8 End of Life (EOL) announcement in December 2021, the operating system’s life cycle has been reduced short. As a result, RHEL declared that their team would concentrate on CentOS Stream in the future.

CentOS stream:

A Linux development platform that allows Red Hat developers to collaborate with the open-source community members is CentOS Stream. Red Hat develops the Red Hat Enterprise Linux (RHEL) source code in CentOS Stream before releasing the newer versions. Therefore, it is considered as a part of the open-source development model. This model’s implementation makes CentOS Stream a preview of the future releases of Red Hat Enterprise Linux.

Advantages of CentOS Stream:

  •  It is not much different from CentOS.
  • It extracts new features before the RHEL distribution.
  • It has the potential of having a great development community.
  • This development platform is more agile than the previous one.

Will CentOS Stream replace CentOS Linux?

CentOS Stream version cannot be considered a replacement for the CentOS distribution. It is an RHEL development version. Whereas CentOS is a re-established Red Hat Enterprise Linux version. As a result, CentOS Stream is better suited to people who wish to see if their servers are future-proof and CentOS Linux users if the build is stable enough for their needs. It has its position cause CentOS Stream is the unavoidable and a natural next step towards the advanced innovation of enterprise Linux. It also has a compressed loop of feedback between RHEL developers.

As Red Hat creates future versions of RHEL, feedback loop compression makes it easier for all the voices to be heard, whether they are individual contributors or large partners.

Red Hat also welcomes all developers and partners to participate in CentOS Stream and create their branches, enabling this innovation hub to test solutions to their unique problems. It is accepted that CentOS Stream is the enterprise Linux of the future. It will help the community have an extraordinary impact on the RHEL releases direction. Red Hat internal projects will be passed to CentOS Stream, allowing them to share tactics and best operational practices with the larger community as this work progresses.

CentOS End of Support (EOS) Schedule :

Version Release Date End of Life
CentOS 6 July 10, 2011 November 30, 2020
CentOS 7 July 7, 2014 June 30, 2024
CentOS 8 September 24, 2019 December 31, 2021

Most valuable commands in CentOS:

Here are some commands which will help in working of CentOS, such as:

  1. mv: This is the move command. CentOS users can utilize this command to move a file from one source or directory to any other location or rename a file.
  2. rmdir: This command is used to delete the directory with the content present in it.
  3. touch: This command will help you to creates an empty file. Tit is also known as the make file command.
  4. clear: Want to clear the CentOS terminal screen? Utilize the “clear” command.
  5. ls: This command will list out the content of the specified directory.
  6. sudo yum install <package name>: This command is utilized to install a particular package.
  7. sudo yum update: This command will update all the installed packages.
  8. locate: This command will assist you in finding a file in your system storage
  9. rm: rm command is used to removes the files.
  10. mkdir: Utilize this useful command for creating new subdirectories and directories.
  11. cd: You can also modify a directory or move the control to any other folder from the current working directory.
  12. man: To print a manual related to any command, use the man command in your CentOS terminal.

Why IT leaders love CentOS?

  • CentOS installation is simple and fits all enterprise provisioning requirements, whether scaling up or down.
  • Linux deployments are less expensive, especially when switching from RHEL to CentOS.
  • It’s everything your team expects from an operating system that should simply operate in today’s workplace.
  • Even for extensive updates, production upgrades are simple and rarely cause downtime because the upgrade process is smooth.
  • Add value, extend, and tweak whatever you want; for example, no vendor lock-in for whatever reason.
  • Want to change something? Your team can do it without going outside the boundaries of your license.
  • With community maintainer Docker Hub images that can be pulled down often with no limitations, you can reliably spin up, update, and transfer between environments.

How will CentOS play its role in your career growth?

  • If you’re seeking a job as a Linux administrator, having experience with CentOS will make you more appealing to employers.
  • Besides this, as a freely available open-source project, you will benefit from contributing to it.
  • Also, using it as the core platform, one may expect to conduct software development.
  • It will make you comfortable working with practically any other Linux distribution.

Conclusion:

CentOS offers a community-driven free software project built to provide a robust platform for the open source communities to grow. It also provides a development environment for most hosting communities, cloud providers, scientific data processing, etc. We have delivered the essential information related to CentOS in our post. This guide includes CentOS history, features, architecture, repositories, major releases and their End of Support schedule, and much more. Moreover, we also explained that how CentOS distribution will help you in your career growth.

About the author

Talha Saif Malik

Talha is a contributor at Linux Hint with a vision to bring value and do useful things for the world. He loves to read, write and speak about Linux, Data, Computers and Technology.