For the CentOS users that have decided to switch to another RHEL fork, rather than distro hop entirely, they'll face the question of, "Which distro should I use? AlmaLinux or Rocky?"
In this guide, we'll compare AlmaLinux and Rocky Linux across a few key areas. We'll weigh their pros and cons, see how they stack up against each other, and ultimately give you enough information to help you decide which one you should use.
Both distros, like CentOS, are free. They have the same goal, which is to bring you enterprise-grade, production-ready Linux in the form of a downstream release of RHEL. One of the key differences between the distros is how their code is maintained.
AlmaLinux is built and maintained by the developers at CloudLinux, a company that provides server hosting and Linux software. It's a company experienced with RHEL forks, having built and maintained their in-house distro called CloudLinux OS, a fork itself, for more than a decade. Going forward, CloudLinux promises to involve the community as much as possible when it comes to the direction of the distro.
Rocky Linux is headed up by Gregory Kurtzer, the original founder of CentOS. Rocky Linux is community-driven, and doesn't have the commercial developers on payroll the way AlmaLinux does. Depending on your point of view, this could be either a good or bad thing. One could also argue that if Kurtzer would have had CentOS' interests in mind in the first place, it wouldn't have been swallowed up by Red Hat and undergone the change in direction.
Bottom Line: Knowing how both of these distros are funded and supported could play a big role in which one you choose to use. Do you go with AlmaLinux, backed by CloudLinux sponsoring it with $1 million annually? Or do you go with Rocky, who has its own set of sponsors and will be maintained by the community?
Comparison to CentOS
Both distros aim to be binary compatible with RHEL. It's a little early to make direct comparisons to CentOS, but you should be able to switch from CentOS to either AlmaLinux or Rocky Linux while experiencing very little differences, and minimal downtime. Currently, it's possible to migrate from CentOS to AlmaLinux in just a few steps. Rocky Linux, upon release, is also expected to have an easy-to-follow migration method.
Bottom Line: It's too early to get into a detailed analysis, but both distros seem perfectly viable as replacements for CentOS, and should operate in much the same way as their predecessor.
First to Market
AlmaLinux was released in January 2021, and Rocky Linux is slated for February-March 2021. While not much a difference, it definitely plays a factor in people's decisions - even though it probably shouldn't, since the releases will be in beta and best practice dictates that they shouldn't be adopted for production environments until proven invariably stable.
Bottom Line: CentOS is supported until the end of 2021, so there's no need to rush into switching. If you're desperate, AlmaLinux has the edge since it's released first. However, waiting until both distros go through the initial growing pains would be the best bet.
AlmaLinux and Rocky Linux naturally have a lot of similarities, but have some big differences in how they're maintained. Both distros are expected to be viable replacements for CentOS, and it probably won't make a huge difference which one you use. Being that they're both binary compatible with RHEL, you could theoretically switch between Alma and Rocky if it ever became necessary. Once the dust has settled, we recommend basing your decision on whichever developer you feel uses the most favorable practices to maintain their operating system.