Rocky Linux

Rocky Linux is an RHEL-compatible distribution initiated by Gregory Kurtzer, co-founder of CentOS, after the end of traditional CentOS. With its core philosophy of “community-owned and community-driven,” it quickly became one of the most popular CentOS alternatives.

Origin Story

Gregory Kurtzer and CentOS

Gregory Kurtzer was one of the co-founders of the CentOS project. In 2004, he helped create CentOS to provide the community with a free RHEL-compatible distribution. He later left the CentOS project to focus on high-performance computing.

The Birth of Rocky Linux

In December 2020, when Red Hat announced the early EOL of CentOS Linux 8, Kurtzer announced on the same day in the CentOS mailing list that he would create a new project to continue CentOS’s original mission.

The project was named Rocky Linux after the late CentOS co-founder Rocky McGaugh, in honor of his contributions to the community.

Release Timeline

Date	Event
2020-12	Project announced
2021-04	Rocky Linux 8.3 RC released
2021-06	Rocky Linux 8.4 GA released
2022-07	Rocky Linux 9.0 released
2025	Rocky Linux 10 released

Rocky Enterprise Software Foundation (RESF)

Rocky Linux is managed by the Rocky Enterprise Software Foundation (RESF), a public-benefit organization.

Organization Structure

RESF uses a flat, team-based governance structure:

Leadership Team: Overall project direction and decisions
Release Engineering: Version releases and build system
Infrastructure: Infrastructure management
Design: Branding and visual design
Documentation: Documentation maintenance
Testing: Quality assurance and testing
Security: Security response

Core Principles

Community-owned, community-driven
Never controlled by a single company
Code, build system, and infrastructure all open source
Transparent decision-making process

RHEL Compatibility Strategy

Rocky Linux’s compatibility goal is bug-for-bug compatible — meaning not just functional parity, but consistent behavior even with known bugs.

Source Code Acquisition

After Red Hat restricted direct RHEL SRPM access in 2023, Rocky Linux obtains source code through:

CentOS Stream git repositories
UBI (Universal Base Image) containers
SRPMs obtained through paid RHEL subscriptions (complying with GPL)
Publicly available source code

The Rocky Linux team emphasizes that their practices fully comply with open-source licensing requirements.

Compatibility Verification

Rocky Linux maintains an RHEL compatibility test suite to ensure:

All RHEL RPM packages can be installed on Rocky Linux
Complete ABI/API consistency
System behavior matches RHEL

Peridot Build System

Peridot is Rocky Linux’s independently developed, fully open-source, cloud-native build system.

Features

Kubernetes-based distributed builds
Multi-architecture parallel building (x86_64, aarch64, etc.)
Complete build provenance and transparency
Anyone can deploy and audit it

Why Build a Custom Build System

Traditional EL rebuild projects typically use Koji (Fedora/CentOS’s build system). Rocky Linux chose to build Peridot to:

Achieve complete build transparency
Avoid dependency on a single upstream tool
Support more flexible build pipelines
Enable community members to independently verify build results

# Peridot source code
https://github.com/rocky-linux/peridot

Migration Tools

migrate2rocky

migrate2rocky is the official tool for migrating existing EL systems to Rocky Linux:

# Download the migration script
curl -O https://raw.githubusercontent.com/rocky-linux/rocky-tools/main/migrate2rocky/migrate2rocky.sh

# Run migration (from CentOS Linux 8, AlmaLinux 8, Oracle Linux 8, etc.)
sudo bash migrate2rocky.sh -r

# Reboot after migration
sudo reboot

Supported migration sources:

CentOS Linux 8
AlmaLinux 8/9
Oracle Linux 8/9
RHEL 8/9 (requires unregistering)

Migration Notes

Always back up important data before migration
Check third-party repository compatibility
If using CentOS SIG repositories, verify Rocky Linux has corresponding repos
Run dnf distro-sync after migration to ensure all packages are synchronized

Installation and Configuration

Getting Rocky Linux

Download: rockylinux.org/download

Available image types:

DVD: Full installation image
Minimal: Minimal installation
Boot: Network installation boot
Cloud Images: GenericCloud, EC2, Azure, GCP
Container Images: Docker Hub, Quay.io
Live Images: GNOME, KDE, XFCE desktops

Post-Installation Setup

# Check system version
cat /etc/rocky-release

# Update the system
sudo dnf update -y

# Enable CRB repository
sudo dnf config-manager --set-enabled crb

# Install EPEL
sudo dnf install -y epel-release

# Install common tools
sudo dnf install -y vim wget curl tar bash-completion

Repository Structure

Repository	Description	Default Enabled
baseos	Core system packages	Yes
appstream	Applications and runtimes	Yes
crb	Developer tools and libraries	No
extras	Additional tools	Yes
highavailability	HA components	No
nfv	Network Function Virtualization	No
plus	Rocky-specific enhanced packages	No
rt	Real-time kernel	No

Rocky Linux Plus Repository

The plus repository contains Rocky Linux-specific enhanced packages:

# Enable the plus repository
sudo dnf config-manager --set-enabled plus

# List packages in the plus repository
sudo dnf repo-pkgs plus list

Commercial Support: CIQ

CIQ (Ctrl IQ) is the company founded by Gregory Kurtzer that provides commercial support for Rocky Linux:

Enterprise-grade technical support
Security hardening and compliance
Performance optimization
Migration services
Training and consulting

CIQ also provides Apptainer (formerly Singularity) and other HPC solutions.

Community and Contributing

How to Participate

Forums: forums.rockylinux.org
Chat: Mattermost (chat.rockylinux.org)
Code: github.com/rocky-linux
Wiki: wiki.rockylinux.org

Architecture Support

x86_64
aarch64 (ARM64)
ppc64le (IBM POWER)
s390x (IBM Z)

SIGs (Special Interest Groups)

Rocky Linux has its own SIG system:

Kernel SIG: Kernel customization and real-time kernel
Cloud SIG: Cloud images and integration
Desktop SIG: Desktop environments
HPC SIG: High-performance computing
Security SIG: Security hardening

Ideal Use Cases

Rocky Linux is particularly well-suited for:

CentOS migration: Smooth migration from traditional CentOS Linux
Production servers: Web services, databases, application servers
Enterprise IT: Organizations needing a free RHEL-compatible system
Research and education: Academic computing infrastructure
Container hosts: Systems running Podman or Kubernetes

Summary

Rocky Linux carries the mission of continuing the traditional CentOS spirit. Through its open build system and independent foundation governance, it has earned widespread community trust. Its bug-for-bug compatibility goal, fully open-source Peridot build system, and active community make it a strong contender among RHEL-compatible distributions.

Versions and Support Lifecycle

Rocky Linux Version	Based on RHEL	Release	Maintenance EOL
Rocky Linux 8	RHEL 8.x	2021-06	2029-05
Rocky Linux 9	RHEL 9.x	2022-07	2032-05
Rocky Linux 10	RHEL 10.x	2025	2035

Rocky Linux 10 was released in 2025 alongside RHEL 10, bringing Python 3.12 as default, Podman 5.x, modularity deprecation, and other new features (the package manager is still DNF 4.20).