AlmaLinux project climbs down from being a one-to-one RHEL clone
A worrying concession means that the shape of the marketplace is changing
Comment The AlmaLinux distribution's goal is shifting from being one-to-one, bug-for-bug compatible with Red Hat Enterprise Linux (RHEL) to being application binary interface (ABI) compatible. But this represents a larger shift in the enterprise Linux market.
Management has published its third statement of direction following Red Hat's withdrawal of publicly accessible source code for its RHEL distribution. In a post entitled "The Future of AlmaLinux is Bright", project lead Benny Vasquez says that from now on, AlmaLinux will aim to be compatible with RHEL at the ABI level, rather than an exact clone as it originally set out to be.
ABI compatibility in our case means working to ensure that applications built to run on RHEL (or RHEL clones) can run without issue on AlmaLinux. Adjusting to this expectation removes our need to ensure that everything we release is an exact copy of the source code that you would get with RHEL.
This is a fairly substantial climb down for the project, and it also represents a significant point of divergence between AlmaLinux and Rocky Linux. In combination with the recent comment from Oracle and SUSE's announcement of a fork, the RHEL rebuild landscape seems to be changing rapidly – which is presumably what Red Hat wanted to happen.
One executive summary of the story so far could run something like this: Rocky Linux is trying to do whatever it can to find ways of accessing the Red Hat source code that's now only available to customers, so that it can continue to offer a one-to-one clone. However, its statement that "while we continuously explore other options, the aforementioned approaches are subject to change" sounds like a quiet expression of caution. This may be why it is now working with SUSE. The German enterprise Linux giant says it's doing something significantly different: a free fork of RHEL.
SUSE, as we said, had already built an internal RHEL clone, originally code named Liberty Linux. We are not privy as to whether that project has been ticking along in maintenance mode, but even if it hadn't, it wouldn't be so hard to revive something it had already constructed.
Part of the original plan was to run this on top of a version of its own enterprise kernel from its SLE distribution. Yes, arguably, the company is helping to create a competitor to its own paid-for product line – but the contrasting interpretation is that it's helping to maintain an existing free competitor to the flagship product of its largest commercial rival. In openSUSE Leap, it already offers a free build of its enterprise kernel; it already offers free public build infrastructure, the Open Build Service.
Combine these with source code obtained from the RHEL universal base images (UBIs), and you have a low-cost way to reduce a competitor's profit margin… and arguably to exhibit and promote your enterprise kernel, its stability, its driver ecosystem, and your build tooling. Not such a bad deal, all in all.
- SUSE announces its own RHEL-compatible distro... again
- Oracle pours fuel all over Red Hat source code drama
- Red Hat's open source rot took root when IBM walked in
- Rocky Linux details the loopholes that will help its RHEL rebuild live on
Oracle isn't actually saying anything very technically specific at all, just general statements about openness, to which we'd respond: let's see you open up openSolaris again, then, and while you're at it, all the other Sun code that you no longer sell. We suspect that because the company already offers its own variant kernel for its RHEL clone, it feels that it can continue with business as usual. It seems possible that future Oracle Linux releases will switch to only offering Oracle's UEK, its Unbreakable Enterprise Kernel, and quietly drop the Red Hat Compatible Kernel, or RHCK, package.
Putting these things together, it could be that what's going to happen is this: Oracle Linux continues, but henceforth offers only its own kernel build, the UEK. If Rocky's clever cloud-VM-instance route is cut off, it may be getting ready to switch to a SUSE-built kernel. And AlmaLinux looks like it might be getting ready to go it alone, possibly building kernels based on the CentOS Stream project.
We remain confident that, thanks to its armies of lawyers, the Big Purple Hat is sticking strictly to the letter of the law when it comes to license compliance, especially the GPL.
No other Linux distribution has exact replicas out there in production use quite like this, although the relationship between openSUSE Leap and SLE comes very close, especially since SUSE synchronized their code bases a few years ago.
Even so, Red Hat's move continues to anger a great many people in the wider FOSS community. We have seen arguments that it is counter to the spirit of open source, as well as ones that the RHEL clones contribute indirectly but significantly to the company's success, such as by providing tools for people to get familiarity and skills with the distro. One strong position is that RHEL is built on the back of code that people have contributed for the good of the community, and as such, Red Hat doesn't get to gatekeep access to that code – for example, by restricting people's Four Freedoms via customer contracts or usage policies.
This may be true, but it would be hard to prove in a court of law. It also must be said that Red Hat itself does provide free licences for people to develop their skills, along with two free-to-use distributions: CentOS Stream and the Fedora family. We don't think Red Hat is going to back down on this, and it looks increasingly like the move has been successful, inasmuch as the company sought to eliminate free identical clones of its paid-for distro. It looks like it's done so, but at the price of destroying some goodwill… a commodity of which it did not have an abundance in the first place.
Overall, as well as being good for Red Hat's profits, at least in the short term, we think that this will be good for the greater enterprise Linux market and ecosystem. It could turn out to be beneficial for SUSE and for Canonical, but we also hope to see it result in more investment in, and sponsorship of, Debian and its financial backer, Software in the Public Interest. ®