CentOS to RHEL

As a long-time Fedora, CentOS, and RHEL user I originally saw this transition to CentOS Stream as a “cash grab” by Red Hat to kill something I loved in the CentOS project and force everyone to RHEL. To understand why this was an incorrect assumption on my part and the part of many others please keep reading. If you prefer the TL;DR please skip ahead to the conclusion. 

What is happening?  

Red Hat is making a strategic change in its development model that will allow it to better serve its ecosystem of partners and customers.  To facilitate this, CentOS is transitioning from being a downstream project rebuilding RHEL Source to being the upstream for RHEL.  This is in line with other Red Hat Sponsored Projects that feed into Red Hat products ready and validated for production workloads.  Look to oVirt (RHV), Keycloak (RH SSO), FreeIPA (RH IDM), etc. This allows for the broader open source community to contribute development cycles on the upcoming RHEL platform in an environment that serves as a middle ground between the rapid pace of Fedora and the Stable “completed” release that is RHEL.  This also gives the broader RHEL/Enterprise Linux community better opportunities to test what is coming next to Stable RHEL Releases. 

1. CentOS going EOL:

End of Lifetime (EOL) Dates
	CentOS 6	CentOS Linux 7	CentOS Linux 8	CentOS Stream 8
Full Updates	2017-05-10	2020-08-06	2021-12-31	2024-05-31
Maintenance Updates	2020-11-30	2024-06-30	2021-12-31	2024-05-31

2. Moving forward, stream will follow the “Full Support” life cycle of the downstream RHEL release. For example, RHEL 8 full support ends 5/31/2024 and CentOS Stream 8 goes EOL (End of Life) 5/31/2024. This is in line with keeping stream a development upstream of active RHEL releases. More information on life cycle dates are available here.

Why is this happening? 

Red Hat is putting CentOS Stream ahead of RHEL development so that it can collaborate faster and more transparently, delivering richer innovation faster to its customers.

1. More Innovation – This moves RHEL inline with other major Linux distributions that have an intermediary between bleeding edge (Fedora) and LTS (RHEL).
2. Faster feature release to RH Customers – This allows for the community of developers to develop on RHEL +1 releases as part of their Development/QA pipeline.  
3. Broader Community Involvement in RH Ecosystem – This opens up RHEL development from being closed inside of Red Hat to being more open in line with the rest of the Open-Source community.   

“CentOS Stream is meant to bridge the gap and let the community contribute and have a say in the direction of development for RHEL.”

Why should I transition to RHEL?

The greatest benefit of transitioning to a Red Hat subscription is the Access and Advocacy Red Hat provides over going it alone with upstream Open Source Projects.

RHEL Subscription Benefits
Access	Advocacy
Open source enterprise software	Visibility into RHEL roadmap
Emerging open source technologies	Influence over RHEL roadmap
10+ year lifecycle	Customer needs in open source projects
Support and Expertise	Hardware, software, & cloud collaboration
Security & performance resources	Security & performance needs

Transitioning to a RHEL Subscription also gives you enhanced support and manageability over what was provided openly via the CentOS Project.  These are some of the more valuable ways that Red Hat helps ensure customer success through its mission of Access and Advocacy: 

• Up to 10 years of updates and support for major releases, two years of updates and support for minor releases, and binary compatibility between releases lets you plan for long-term success. In contrast, the CentOS Project provides only limited access to resources and advocacy for users, making it a less valuable choice for enterprise deployments. 
• Red Hat customers receive binary patches for high-priority bugs immediately. CentOS Linux users often do not receive the equivalent patches until at least 6 weeks later. 
• The CentOS Project stops delivering patches for CentOS Linux releases when the standard production support period for the equivalent version of Red Hat Enterprise Linux ends. To continue receiving patches, CentOS Linux users must immediately upgrade to the next release once it is available. 
• All active Red Hat Enterprise Linux subscriptions include access to live kernel patches for critical and important Common Vulnerabilities and Exposures (CVEs) at no extra cost. The CentOS Project does not provide live patches for CentOS Linux.
• A seamless, nondisruptive migration process for existing Red Hat Enterprise Linux deployments lets you upgrade more easily. And a predictable, time-based release cadence makes it easier to plan and schedule larger datacenter and system updates, upgrades, and transitions.
• Red Hat Enterprise Linux includes many new systems administration and security features — including a web-based management console, a new package control method, and the Red Hat Insights analytics solution, to simplify and streamline IT operations. 
• Red Hat Insights delivers unique predictive operating system analytics that let you rapidly identify and remediate threats to availability, security, stability, and performance. Proactive, automated, targeted issue resolution helps to ensure that your environment is operating optimally to avoid problems and unplanned downtime. Every active Red Hat Enterprise Linux subscription now includes access to Red Hat Insights. 
• Red Hat security, a dedicated team of engineers, monitors, identifies, and proactively notifies customers of risks. This team remediates vulnerabilities by creating, testing, and delivering security patches to all versions of Red Hat Enterprise Linux in their supported life cycles. 
• Red Hat security engineers ensure Red Hat Enterprise Linux and other offerings are certified and comply with government and commercial security standards.

Why not transition to Stream?

CentOS Stream should be considered a “Preview” of what is to come in Stable RHEL releases rather than a stable release in and of itself.  While CentOS Stream aims to be just as reliable, compatible, and secure as RHEL, it is not a certified release and truly is a development-oriented Linux distribution.  This is summed up perfectly by the mission statement on the CentOS Stream webpage.

Continuously delivered distro that tracks just ahead of Red Hat Enterprise Linux (RHEL) development, positioned as a midstream between Fedora Linux and RHEL. For anyone interested in participating and collaborating in the RHEL ecosystem, CentOS Stream is your reliable platform for innovation.

CentOS Stream mission statement

Where to use CentOS Stream?

Development/QA to ensure applications will work on the upcoming RHEL release (RHEL Current +1).  CentOS Stream is the perfect tool for use in validating that your applications will run smoothly on upcoming RHEL releases as well as targeting development at upcoming RHEL releases.  It can also be useful for validating that highly customized deployments will continue working in upcoming RHEL releases.  I have also personally found that Stream can be a great Workstation OS splitting the difference between stable RHEL and bleeding Edge Fedora for users that want package updates more frequently, but don’t want the very frequent updates that come with using Fedora on their workstation.

How hard is it to transition to RHEL?

For many standard installations converting from CentOS to RHEL is a simple matter of using the official Red Hat tool, Convert2Rhel. If you have a more customized installation such as one with custom kernel modules or systems running in FIPS mode, then the conversion can be more involved.  This is where Professional Services can be an excellent value-add as part of your transition to RHEL.  For additional details on the Conver2Rhel tool please see the following RH article.

What about my development costs when targeting stable RHEL releases?

Red Hat understands that development efforts also need resources and wants to help ensure developers have access to target the Red Hat platform.  To help facilitate this there are two developer programs that you should be aware of.  

Red Hat Developer Program for Individuals:

1. No Cost Program for Individual Developers.
2. Full access to RHEL on up to 16 instances.
3. Usable for small production, self-supported, workloads.

Red Hat Developer Program for Teams: 

1. Allows larger internal teams to have the same no-cost development access to RHEL.
2. Addition to an existing subscription that can be requested via your RH account team.
3. See the following Red Hat article for more details.

Resources for Open Source and Academic Programs to reduce costs of migration from CentOS to RHEL 

ROSI (No-Cost Sub’s for Opensource Projects, Standards Orgs, Research):

1. Supporting the open source software ecosystem is a core objective for Red Hat and they are further supporting it by extending no-cost RHEL subscriptions to open source oraginzations.
2. In the future this will include more products from Red Hat’s technology portfolio.
3. See the following Red Hat article for more details.

Red Hat Academic Program for Educational, Not For Profit Research, etc:

1. Red Hat understands the unique challenges facing Educational Institutions and has developed a specific Subscription level tailored to these needs. Red Hat academic offerings are intended to support education initiatives in the academic community at an affordable price. 
2. See the following Red Hat article for more details.

In circling back to the start of this article what Red Hat has done is appropriately integrate the CentOS Project into the RHEL Development lifecycle providing, for the 1st time, a publicly available upstream of RHEL where previously all RHEL development was behind closed doors at Red Hat. This change to the development of RHEL is far more inclusive of the broader community and moves RHEL in line with other Red Hat products that have an upstream Open Source project feeding into them. Alongside this change to the CentOS project, they have also released some no-cost/low-cost developer programs intended to provide access to the normal RHEL releases that would be used in production. In my eyes, this is better than the old way of developing on CentOS to target RHEL as there were/are still minor differences between the two. 

If you need someone in your corner to assist in transitioning to RHEL—WorldTech IT offers enterprise-class Red Hat Professional Services / Consulting and options for emergency support through our Always-On program. Our engineers combine extensive experience in the application delivery and security space with broad expertise in the Linux and open-source community.