Red Hat, CentOS's Linux parent company, announced it was "shifting focus from CentOS Linux, the rebuild of Red Hat Enterprise Linux (RHEL), to CentOS Stream, which tracks just ahead of a current RHEL release." In other words, CentOS will no longer be a stable point distribution but a rolling release Linux distribution. CentOS users are ticked off.
Why? First, you need to understand what's going on. A rolling-release Linux is one that's constantly being updated. Examples of these include Arch, Manjaro, and openSUSE Tumbleweed. Here, CentOS Stream will be RHEL's upstream (development) branch. This may sound like CentOS will be RHEL's beta, but CentOS denies this.
In the CentOS FAQ, the company states: "CentOS Stream will be getting fixes and features ahead of RHEL. Generally speaking, we expect CentOS Stream to have fewer bugs and more runtime features than RHEL until those packages make it into the RHEL release."
Continuing on, the fixed-release model is the one most server Linux distributions have historically used. For example, besides Red Hat using it for RHEL, Canonical uses it for its mainstream Ubuntu Linux release and SUSE uses it for SUSE Linux Enterprise Server (SLES). In fixed releases, major distributions are made on a schedule, with security patches and minor updates made as needed.
Each approach has its advantages and disadvantages. For instance, with a rolling release, major bugs might appear in a production system. On the other hand, in a fixed-release Linux, major improvements may take months, or even years, to appear.
Some rolling release Linux distributions are used in production. These tend to be Internet of Things (IoT) Linux operating systems such as Fedora IoT, Clear Linux, and Ubuntu Core. They're not used for servers, where stability and a wide variety of programs are valued more highly than running the latest, bleeding-edge software.
In any case, it's very clear that Red Hat doesn't see CentOS Stream as a production server. As a server for RHEL customers to use to see what the next version of RHEL will bring to them, yes, but for day-to-day work? No.
As Chris Wright, Red Hat's CTO, said when CentOS Stream was introduced, "developers … require earlier access to code, improved and more transparent collaboration with the broader partner community, and the ability to influence the direction of new RHEL versions. It is these opportunities that CentOS Stream is intended to address."
Then, however, it was to be, as Wright said, "a parallel distribution to existing CentOS." You see, CentOS is an extremely popular server operating system in its own right. I run it myself both on servers in my home office and TMDHosting.
I'm far from alone. By W3Tech's count, while Ubuntu is the most popular Linux server operating system with 47.5%, CentOS is number two with 18.8% and Debian is third, 17.5%. RHEL? It's a distant fourth with 1.8%.
If you think you just realized why Red Hat might want to remove CentOS from the server playing field, you're far from the first to think that. For years, CentOS has been the choice of experienced Linux administrators who felt little need for support, while RHEL was what companies chose who wanted the belts and suspenders of full support.
Now, with this move, thousands of companies will need to move to a different Linux variant. They're not happy.
Red Hat will continue to support CentOS 7 and produce it through the remainder of the RHEL 7 life cycle. That means if you're using CentOS 7, you'll see support through June 30, 2024. Red Hat may also offer extended life cycle support for RHEL and CentOS 7, but that hasn't been decided yet.
As for CentOS 8, that's another story. Red Hat will only continue to update it until the end of 2021. CentOS 8 users had expected support until 2029. They're livid.
On Hacker News, the leading comment is: "Imagine if you were running a business, and deployed CentOS 8 based on the 10-year lifespan promise. You're totally screwed now, and Red Hat knows it. Why on earth didn't they make this switch starting with CentOS 9???? Let's not sugar coat this. They've betrayed us."
Over at Reddit/Linux, one person wrote, "The use case for CentOS, is completely different than CentOS Stream, many many people use CentOS for production enterprise workloads not for dev, CentOS Stream may be ok for dev/test but it is unlikely people are going to adopt CentOS Stream for prod."
Another Redditor wrote, "We based our Open Source project on the latest CentOS releases since CentOS 4. Our flagship product is running on CentOS 8 and we *sure* did bet the farm on the promised EOL of 31st May 2029."
He continued, "CentOS Stream" is supposedly now the new answer, but the obvious downside is that stability and dependability get sacrificed on the altar of bleeding edge. In the past, we could bet an even money on the fact that something built in the X.0 release of the OS would still run fine when the OS went EOL. The deviations from this were few and usually happened for good reasons." He concluded, "I'm not happy. But hey, cool. If Red Hat is butchering the horse we bet our livelihood on, then we'll move elsewhere and take a couple of thousand clients with us. /shrug."
Not everyone hates this move. Jim Perrin, now a Microsoft Principal Program Manager and former Red Hat developer and CentOS Board member, wrote this new CentOS approach has three advantages:
It makes RHEL development more transparent and reliable.
It provides a way for ISVs and developers to contribute fixes and features.
It provides a way for the community to provide feedback.
For Perrin, "CentOS Stream provides a way for users to submit pull requests and to make their case for why it should be included. This obviously doesn't mean everyone will get their way, but it's a stark improvement from the past."
Wright, in a blog post, argues that the CentOS Stream is stable enough for production. CentOS Stream is a "rolling preview" of what's next in RHEL, both in terms of kernels and features. Facebook runs millions of servers supporting its vast global social network, all of which have been migrated (or are migrating) to an operating system they derive from CentOS Stream.
From where Wright sits, "CentOS Stream isn't a replacement for CentOS Linux; rather, it's a natural, inevitable next step intended to fulfill the project's goal of furthering enterprise Linux innovation."
Wright explained, "The technology world we face today isn't as simple as what we faced even a year ago, let alone five years ago. From containerized applications and cloud-native services to rapid hardware innovations and ecosystems shifting to Software-as-a-Service (SaaS), the operating system can be hard-pressed to answer even one of these needs, especially at scale and in a responsive manner. This is where we see CentOS Stream fitting in. It provides a platform for rapid innovation at the community level but with a stable enough base to understand production dynamics."
In other words, Red Hat and CentOS sees a world where the best features of the rolling release and point release methods are combined. They may be right. But many users and businesses would have appreciated more time and warning that the way they'd been using CentOS for years was going to be pulled out from underneath their feet.