CentOS Linux
By The CentOS Project
Typical implementation process for CentOS Linux and the approximate time each step may take:
Decide on CentOS version (e.g., CentOS Stream, legacy CentOS).
Obtain the appropriate CentOS ISO image from the official website.
Create a bootable USB drive or DVD using the downloaded ISO.
Partition disks, select packages, and configure basic settings (timezone, user accounts).
Apply system updates.
Configure firewalls and security policies.
Test connectivity and system stability.
CentOS Linux can be highly customized to fit specific business needs. Here are multiple data points and examples demonstrating its flexibility:
Third-party repositories: Add custom or third-party repositories for specialized software.
Custom scripts: Use shell scripts or other languages to automate repetitive tasks.
Custom kernels: Compile and run custom kernels for advanced requirements.
VPN and network services: Set up VPNs, proxies, and advanced routing as needed.
RAID and LVM: Configure RAID arrays and Logical Volume Management for advanced storage needs.
Containers: Deploy Docker, Podman, or Kubernetes for containerized applications.
Examples: NFV (Network Functions Virtualization), storage, alternate kernels, and more.
Live and WSL images: Use or create live images and Windows Subsystem for Linux (WSL) images for specific use cases.
Custom drivers: Add or modify drivers for unique hardware requirements.
The training and support options available for new users of CentOS Linux:
Special Interest Groups (SIGs): Many SIGs provide specialized guides and documentation for their focus areas (e.g., storage, networking, virtualization).
IRC/Chat: Real-time help is available via IRC channels and other chat platforms.
Events & Promotion: The Promo SIG organizes events and social media activities to engage and educate users.
Third-party Tutorials: Many external websites and YouTube channels offer step-by-step guides for beginners.
RHEL Compatibility: Since CentOS closely tracks Red Hat Enterprise Linux (RHEL), most RHEL training materials and courses apply to CentOS.
The security measures CentOS Linux puts in place to protect data:
Default Enabled: SELinux is enabled by default and can be customized for different security policies.
iptables/nftables: Advanced users can configure lower-level firewall rules for granular network protection.
Stream Model: CentOS Stream delivers updates continuously, often ahead of RHEL, ensuring the latest security fixes.
Sudo: Controls and logs administrative access, reducing the risk of privilege escalation.
Encrypted Communications: Encourages the use of SSH, TLS, and other encrypted protocols for secure data transfer.
System Logs: Centralized logging of authentication attempts, system changes, and network events.
AIDE (Advanced Intrusion Detection Environment): Monitors file integrity and alerts on unauthorized changes.
Package Signing: All official packages are cryptographically signed to prevent tampering.
Service Isolation: Uses systemd to isolate and sandbox services.
CentOS Linux releases updates, and how those updates are managed (based on information from centos.org):
This means users receive updates more frequently than with traditional point-release distributions.
There are mechanisms for faster critical updates, especially for production environments running CentOS Stream.
yum (legacy, still supported for compatibility)
Additional repositories may be enabled for Special Interest Group (SIG) content or third-party software.
Users can choose to apply all updates, only security updates, or select specific packages as needed.
CentOS Linux is an open-source operating system, and as such, its policy on data ownership and portability is shaped by open-source principles and the absence of proprietary lock-in. Here’s what this means for users:
User-Controlled Data: All data stored, processed, or generated on a CentOS Linux system belongs entirely to the user or organization operating the system.
No Vendor Lock-In: CentOS does not impose any restrictions, licensing, or claims of ownership over user data. The project does not collect, access, or manage user data by default.
Open Source Licensing: CentOS is distributed under open-source licenses (primarily GPL), which do not grant the project or its contributors any rights over user data.
Full Data Access: Users have unrestricted access to all files, databases, and configurations on their CentOS systems.
Standard Formats: CentOS uses widely adopted Linux file systems (e.g., ext4, XFS) and standard data formats, making it easy to move data between systems.
Backup and Migration Tools: Standard Linux tools (rsync, tar, scp, etc.) can be used to back up or migrate data to other CentOS, Linux, or even non-Linux systems.
Virtualization and Cloud: CentOS supports export/import of virtual machine images and containers, further enhancing portability.
The terms for scaling up or down with CentOS Linux as your organizational needs change, based on open-source principles and information from centos.org:
Unlimited Scaling: CentOS Linux is free and open-source, so you can deploy as many (or as few) instances as needed without worrying about per-server fees or licensing restrictions.
No Contracts: No contracts or commitments dictate minimum or maximum usage.
Physical, Virtual, and Cloud: CentOS can be installed on physical servers, virtual machines, containers, and in public/private clouds. This makes it easy to scale infrastructure up or down as needed.
Standard Images: Downloadable ISO, cloud, and live images are available for rapid deployment
Special Interest Groups (SIGs): SIGs offer tools and documentation for deploying CentOS in specialized, scalable environments (e.g., storage, virtualization, networking).
Storage and Network Solutions: SIGs provide scalable storage (Ceph, Gluster, NFS, Samba) and networking solutions, supporting both small and large deployments.
Portability: You can freely migrate workloads to and from CentOS without restrictions, making it easy to scale down or switch platforms if needed.
Supported Tools: CentOS works with popular automation, orchestration, and configuration management tools (e.g., Ansible, Kubernetes, OpenStack), enabling automated scaling.
CentOS Linux is a free and open-source operating system governed by open-source licenses (primarily the GPL). As such, it does not require any commercial contract, subscription, or license agreement for use, deployment, or distribution. This has direct implications for contract renewal and cancellation:
No Purchase or Subscription: CentOS Linux does not require users to purchase licenses or subscriptions. There is no commercial contract to renew or cancel.
No Expiry: Your right to use CentOS is perpetual under the terms of its open-source license.
GPL and Other Licenses: CentOS is distributed under the GNU General Public License (GPL) and other open-source licenses. These licenses grant users the freedom to use, modify, and distribute the software without contractual obligations.
No Vendor Lock-In: Users are free to stop using CentOS at any time, migrate to another OS, or fork the codebase without penalty.
No Service Level Agreements (SLAs): CentOS does not provide official commercial support or SLAs; support is community-driven.
No Support Contracts: There are no support contracts to renew or cancel unless you engage a third-party provider.
Self-Managed Upgrades: Users manage their own upgrades and updates. There is no renewal process for continued access to updates—updates are freely available as long as the project maintains them.
The CentOS project does not claim or advertise any compliance status on its official website or documentation.
Important caveat: The official certifications (like FIPS or Common Criteria) apply only to RHEL binaries and environments, not to CentOS.
These are community-driven efforts and do not constitute formal certification.
Implementing third-party validated cryptographic modules.
Responsibility for compliance rests with the deploying organization, not with CentOS itself.
CentOS is often used in development, testing, and non-production environments where formal certification is not required.
