When it comes to enterprise-grade Linux distributions, Red Hat Enterprise Linux (RHEL) has long been the industry standard.  It’s my impression that big enterprises nearly always go with RHEL (at least in the US) unless they’re web-focused or have a large staff of engineers on staff to do OS work, in which case Ubuntu or Debian may be chosen.

In the past, a lot of orgs would use CentOS in their development environments – or, let’s be honest, in their production tiers as well – because CentOS was a 1:1 bit-for-bit clone of RHEL and was free.  But back in 2020, IBM (the owners of RedHat) changed things up by changing CentOS from downstream to upstream.  Now CentOS is a sort of development edition where changes are tested and experiments are made.  This makes it rather useless for most people.

In the wake of this change, two projects (Alma Linux and Rocky Linux) were started to recreate the “1:1” world that CentOS used to offer.  IBM fought back by trying to make its sources inaccessible.  Its perspective was that while the GPL requires distributing source to users, the only legitimate users are those who are RHEL customers, so they were under no obligation to give their sources to Alma and Rocky.

Alma and Rocky took a couple different routes in response to this.  Now that some time has gone by, let’s step back and take a look at the state of RPM-based distros.

Disclaimer: I’ve always been a Debian user (outside of work).  I find it’s easier to setup things I want with apt’s expansive library of software than yum/dnf’s more limited options.  Sure, you can add more repos to RPM-based distros, but that’s extra work.  RHEL and its ilk also have more of a history of constantly changing things and introducing new subsystems.  Some might say change for change’s sake, though there are defensible reasons for some of this owing to Linux’s development model.  I usually recommend Debian for most LowEnd DIY hosters, and it’s the overwhelming favorite in our community.

Red Hat Enterprise Linux (RHEL)

RHEL is a commercially supported Linux distribution that is intended to be used in enterprise environments, mission-critical scenarios, and other use cases which require long-term stability.  Part of its appeal is that big software vendors (SAP, Oracle, etc.) certify their products to run on RHEL.  With a lot of enterprise software, if Linux is supported, it’s RHEL.

RHEL requires an expensive annual subscription.  However, there is a developer option which comes with no support and allows you to (legally) run on up to 16 servers for no cost.

AlmaLinux

AlmaLinux is a free, open-source Linux distribution originally created by CloudLinux as a direct replacement for CentOS.  Alma Linux is not 1:1 compatible with RHEL in the sense that the binaries are bit-for-bit the same.  They aim for ABI compatibility rather than being a strict rebuild.  That means that AlmaLinux may diverge from RHEL.

AlmaLinux is managed by the AlmaLinux OS foundation, a non-profit.

Security patches and other updates closely track RHEL, so if there’s a major vulnerability that is fixed in RHEL, it’ll also be fixed in Alma.  But the AlmaLinux foundation occasionally applies its own improvements.

Rocky Linux

Rocky Linux, founded by Gregory Kurtzer (original co-founder of CentOS), was also designed to fill the gap left by CentOS. Rocky positions itself as a 1:1 downstream rebuild of RHEL.  This means that Rocky aims to be functionally and bug-for-bug compatible with RHEL.

Rocky Linux is governed by the Rocky Enterprise Software Foundation (RESF).

Rocky Linux takes a purist approach, trying to remain as close to RHEL as possible. This means fewer deviations or enhancements beyond what’s in RHEL.

So Which One is Right for You?

Debian!  But seriously…

If you are a Fortune 500, RHEL is the obvious answer because you get support.  And even for small and medium-sized businesses, having a backstop like that has a value for production workloads.

But what about the LowEnder?

If you put a RHEL, Alma, and Rocky Linux system side by side, other than the branding-specific bits, you’d be hard-pressed to tell them apart.  You’re using the same administration commands, the repositories and software feel similar, you’re using the XFS filesystem, kernel versions are the same, etc.

If you’re playing with some enterprise software, then I would probably steer towards RHEL.  For example, I have friends who are Oracle DBAs by trade and want a home lab to play with Oracle.  In their case, they use RHEL with the free developer license.

And of course, RHEL with a developer license is a fine choice in other scenarios.  Rocky Linux is the next-closest thing.  Alma is a little futher off, but not by much.  Alma’s philosophy is more like “why be bug-for-bug compatible when we can just fix the bugs,” so to some extent it positions itself as a RHEL++.

Most LowEnders are going to pick either Rocky or Alma.  For me, if I was going to go over to the dark (RPM) side, I’d probably go with Rocky.  But I could understand Alma as a solid choice as well.  In the end, you may not notice a difference between them.

What about you?  What is your RPM distro of choice and why?  Please let us know in the comments below!

raindog308

Raindog308 is a longtime LowEndTalk community administrator, technical writer, and self-described techno polymath. With deep roots in the *nix world, he has a passion for systems both modern and vintage, ranging from Unix, Perl, Python, and Golang to shell scripting and mainframe-era operating systems like MVS. He’s equally comfortable with relational database systems, having spent years working with Oracle, PostgreSQL, and MySQL.

As an avid user of LowEndBox providers, Raindog runs an empire of LEBs, from tiny boxes for VPNs, to mid-sized instances for application hosting, and heavyweight servers for data storage and complex databases. He brings both technical rigor and real-world experience to every piece he writes.

Beyond the command line, Raindog is a lover of German Shepherds, high-quality knives, target shooting, theology, tabletop RPGs, and hiking in deep, quiet forests.

His goal with every article is to help users, from beginners to seasoned sysadmins, get more value, performance, and enjoyment out of their infrastructure.

You can find him daily in the forums at LowEndTalk under the handle @raindog308.