AWS has released Amazon Linux 2027 in public preview, built on the AL2023 baseline and shipping with SELinux in enforcing mode by default. That default is the change most likely to create work for teams planning a migration, and the announcement does not say when AL2023 support ends or when AL2027 reaches general availability.
AL2027 runs on kernel 7.1 or later, uses AWS-LC for cryptographic operations, and adds accelerator drivers including AWS Neuron support for machine learning workloads. AWS positions it for web applications, databases, containerized microservices, AI and ML workloads, and large-scale infrastructure.
The kernel version is not settled. Benjamin Herrenschmidt, a principal engineer at AWS, noted in a LinkedIn discussion of the release that the kernel will be updated until it reaches LTS, so 7.1 is a starting point rather than what AL2027 ships with at general availability.
SELinux enforcing is the operational difference. AL2023 ships SELinux in permissive mode, where policy violations are logged rather than blocked. Under enforcing mode, they are blocked. Applications that run on AL2023 because SELinux only complained about their behavior will fail on AL2027 unless their file contexts, ports, and access patterns match policy. Validating that is the preview's most useful purpose.
The first question in the community response was about migration rather than features. On Reddit, a commenter asked whether there would be an in-place migration path from AL2023 to AL2027. The question drew more upvotes than any other comment in the thread and no answer from AWS.
Another user replied that cloud-native usage replaces hosts rather than upgrading them in place. The original commenter accepted the principle and named the exception:
I understand, but even in a world of cattle, unfortunately there are always going to be things stuck as pets.
A third suggested EC2 root volume replacement as a partial route for instances that keep no state on the root volume, which covers some cases rather than the general problem.
The gap between release cadence and adoption showed up in the same thread. One commenter noted that he was still working to get teams in his organization onto AL2023.
Preview coverage is broad but incomplete. AMIs are available through the console in all commercial regions in x86-64 and ARM variants, and container base images are on the Amazon ECR Public Gallery. On-premises images are not yet available. A member of the Amazon Linux team, whose GitHub account appears on the project issue tracker, wrote in the same Reddit thread that the team found a last-minute issue and would release those images soon.
The choice of Amazon Linux over other RHEL-derived distributions came up in both threads. One commenter on r/aws said he did not trust IBM to avoid forcing Rocky, Alma or Oracle to re-engineer how they work again, a reference to Red Hat's source availability changes. On r/linux, another placed Amazon Linux against a different comparison:
No, it's more like Oracle Linux. Owned by a terrible company, yes, but it is completely open source and genuinely is no-strings-attached, unlike Oracle Java with its restrictive license. It's not an attempt at vendor lock-in nor is it a proprietary platform.
He added that there is little reason to use it because it is a redistribution of something available elsewhere, which is the counterargument to AWS's cloud-optimization case.
For teams evaluating the preview, the practical work is testing against SELinux enforcing rather than benchmarking the kernel. AWS publishes a full list of changes relative to AL2023 in the AL2027 documentation, and accepts feedback through the AL2027 GitHub repository.