OpenCloudOS

OpenCloudOS is an enterprise-grade Linux distribution initiated by Tencent and co-developed by multiple Chinese technology companies, with deep optimization for cloud computing and cloud-native workloads. Compatibility differs by release: the 8 series is 100% userspace-compatible with CentOS 8, while the 9 series is fully community-developed (per the official FAQ, its kernel and packages are independently selected and maintained).

Overview

OpenCloudOS evolved from TencentOS (Tlinux), Tencent’s internal operating system that ran on millions of servers for years. In 2021, Tencent released it as an open-source community project.

Core Positioning

Enterprise-grade cloud infrastructure operating system
Distillation of Tencent’s decade-plus kernel and OS expertise
Community-operated with multi-company participation
Deep optimization for cloud-native scenarios

Community Organization

Founding and Members

The OpenCloudOS community is led by Tencent, with core members including:

Tencent (initiator and primary contributor)
ZTE Corporation
PowerLeader
China Telecom
Beijing Chuxin
CSDC (China Standard Software)
Phytium Information Technology
Inspur
UCloud
Dozens of additional enterprises

Governance Structure

Board of Directors: Strategic and directional decisions
Technical Committee (TC): Technical roadmap and architecture decisions
SIG Groups: Development and maintenance in specific technical domains

OpenCloudOS Versions

OpenCloudOS 8 (current 8.10)

Compatible with RHEL 8 / CentOS 8
Targets CentOS 8 migration users
Ships with TencentOS Kernel 5.4 LTS
Actively maintained

OpenCloudOS 9 (current 9.6)

Fully community-developed: the official FAQ states the kernel and packages are independently selected, built, and maintained — not based on RHEL 9
Uses a 6.6 LTS kernel (newer than RHEL 9’s 5.14)
Uses updated software stack
Enhanced security features
Under active development

OpenCloudOS Stream

Similar in positioning to CentOS Stream, serving as the development frontier for the next stable release:

Continuous rolling updates
Early access to latest features and improvements
Primary entry point for community contributions

TencentOS Kernel

TencentOS Kernel is the core technical differentiator for OpenCloudOS, drawing from over a decade of Tencent’s internal kernel optimization experience.

Technical Highlights

Performance Optimization

Scheduler enhancements: Cloud-optimized scheduler improving multi-tenant isolation
Memory management: Huge page and memory reclaim optimization
Network stack: High-performance networking with eBPF enhancements
IO optimization: Block device and filesystem performance improvements

Container Optimization

cgroup v2 enhancements
Container-level kernel parameter isolation
Container security hardening
Container performance monitoring

Security Enhancements

Kernel vulnerability hotpatching (similar to Ksplice capabilities)
Enhanced auditing and monitoring
Security hardening patches

# Check the kernel version
uname -r
# Example output: 5.4.xxx.oc8.x86_64 (OpenCloudOS 8) or 6.6.xxx.oc9.x86_64 (OpenCloudOS 9)

# Kernel hotpatching status
# (requires Tencent Cloud environment or related tools)

Production Validation

TencentOS Kernel powers within Tencent:

WeChat
QQ
All Tencent Cloud products
Tencent Games infrastructure
Millions of servers

This massive-scale production validation provides strong endorsement of its stability and performance.

Cloud-Native Optimization

OpenCloudOS’s cloud-native optimizations are a core competitive advantage.

Container Runtimes

Podman, Buildah, and Skopeo integrated by default
Solid support for containerd and Docker
Optimized container images (smaller base images)

Kubernetes Ready

Pre-configured Kubernetes dependencies
Kernel parameters tuned for K8s workloads
eBPF-enhanced network policy support

Microservices Friendly

Service Mesh component optimization
gRPC performance enhancements
High-concurrency network connection optimization

# Install container tools
dnf install -y podman buildah skopeo

# Container-related kernel parameters are pre-tuned
sysctl -a | grep net.core

Installation and Configuration

Getting OpenCloudOS

Download: www.opencloudos.org

Available image types:

DVD ISO (full installation)
Minimal ISO (minimal installation)
Cloud images (Tencent Cloud, AWS, etc.)
Container images

Repository Structure

# OpenCloudOS 8 main repositories
dnf repolist

# BaseOS       Core system packages
# AppStream    Applications and runtimes
# Extras       Additional tools
# PowerTools   Developer tools

Repository	Description
BaseOS	Core OS components
AppStream	Applications, language runtimes, databases
Extras	OpenCloudOS additional tools
PowerTools / CRB	Developer tools and libraries
Plus	Enhanced packages

Basic Operations

# Check version information
cat /etc/opencloudos-release

# System update
dnf update -y

# Third-party repository (differs by series, per the official FAQ):
#   OpenCloudOS 8 (userspace-compatible with CentOS 8) -> EPEL:
dnf install -y epel-release
#   OpenCloudOS 9 (fully community-developed) -> EPOL (the community's own repo;
#   note the spelling, it is not EPEL. Follow the official docs to enable it and
#   do not install EPEL 9 on the 9 series -- see /cloud/opencloudos-guide/)

# Install common development tools
dnf groupinstall -y "Development Tools"

Tencent Cloud Integration

OpenCloudOS is one of the recommended operating systems for Tencent Cloud CVM (Cloud Virtual Machine):

Native Support

Official OpenCloudOS images in Tencent Cloud console
Cloud monitoring and operations tools natively supported
Security components (host security, vulnerability scanning) pre-integrated
Automation (TAT - Tencent Automation Tools) support

Cloud Scenario Optimization

virtio driver optimization
Network acceleration (SmartNIC support)
Storage performance optimization (cloud disk scenarios)
Fast boot optimization for auto-scaling scenarios

# Install cloud monitoring agent on Tencent Cloud
# Typically pre-installed in official images

# Using Tencent Cloud mirror sources
# Official images default to Tencent Cloud internal sources

Migrating from CentOS

OpenCloudOS provides tools and guides for migrating from CentOS:

# Migrate from CentOS 8 to OpenCloudOS 8
# Download migration tools
# See OpenCloudOS official migration documentation for details

Migration Considerations

Back up important data
Check third-party repository compatibility
Verify application behavior on OpenCloudOS
If using TencentOS Kernel, check kernel module compatibility

OpenCloudOS vs Anolis OS

As two cloud-vendor-led EL distributions from China, they share similarities but have distinct differences:

Dimension	OpenCloudOS	Anolis OS
Initiator	Tencent	Alibaba
Custom kernel	TencentOS Kernel	ANCK
Cloud integration	Tencent Cloud	Alibaba Cloud
RHEL/CentOS compatibility	8 (userspace-compatible with CentOS 8); 9 is fully self-developed	7/8
Independent version	Stream	Anolis OS 23
Multi-architecture	x86, ARM	x86, ARM, LoongArch, RISC-V
Community scale	Dozens of enterprises	Hundreds of enterprises
Core strength	Cloud-native/container optimization	Multi-arch/domestic IT

Selection guidance:

Tencent Cloud users: prefer OpenCloudOS
Alibaba Cloud users: prefer Anolis OS
Need LoongArch or other special architectures: choose Anolis OS
Heavy container/K8s workloads: both are solid choices

Community Participation

SIG Groups

SIG	Focus Area
Kernel	Kernel development and optimization
Cloud Native	Cloud-native technology stack
Storage	Storage technologies
Networking	Network optimization
Security	Security hardening
Virtualization	Virtualization support

How to Participate

Website: opencloudos.org
Code repository: github.com/OpenCloudOS
Community forums
Tech meetups and developer events

Ideal Use Cases

Tencent Cloud users: Native best experience and support
Cloud-native workloads: Container and K8s scenarios
CentOS migration: Localized option for users in China
High-performance networking: eBPF and network stack optimization
Large-scale deployment: Validated on Tencent’s millions of servers

Summary

OpenCloudOS represents the commitment and capabilities of a leading Chinese cloud provider in the operating system space. The TencentOS Kernel, validated at massive production scale with cloud-native optimizations, is its standout feature. For Tencent Cloud users and heavy cloud-native workloads, OpenCloudOS is a mature and continuously evolving choice.