The useful SQL Server news this week is not only the April 16 SQL Server 2025 CU4 build. It is what the current Linux release notes say about the operating system layer underneath the database. SQL Server 2025 CU4 lists current packages for RHEL 10 and Ubuntu 24.04, while Microsoft also states that SUSE Linux Enterprise Server is not supported for SQL Server 2025. That turns a database upgrade into a platform decision, not a simple engine-version choice.
This matters because SQL Server on Linux is often treated as a portability story: the same database engine, a different host operating system, and enough tooling discipline to make it work. Production estates need a harder reading. Microsoft supports SQL Server on Linux distributions until the earlier of the distribution support lifecycle or the SQL Server support lifecycle, and the release notes steer production workloads toward supported platforms such as Red Hat Enterprise Linux and Ubuntu Pro. The support boundary is therefore shared between database servicing and OS lifecycle management.
The RHEL 10 and Ubuntu 24.04 path is the positive side of the story. Microsoft announced general availability for SQL Server 2025 on those newer distributions starting with CU1 in January 2026, and the April release notes now show CU4 packages for both. That gives Linux-based SQL estates a clearer modern target, especially where teams want newer kernels, current security baselines, and a cleaner long-term operating model than staying on older distribution versions indefinitely.
The SLES note is the part teams should not gloss over. Microsoft says existing SQL Server deployments on earlier versions of SQL Server running on SLES are not affected, but upgrading to SQL Server 2025 means backing up databases and restoring them to a supported distribution. That is not just a documentation footnote. It affects maintenance planning, automation, monitoring agents, package repositories, HA design, backup validation, and the operational muscle memory of teams that have standardized on SUSE for years.
For mixed IT teams, the lesson is that SQL Server lifecycle planning has to include Linux ownership from the start. The DBA cannot validate the engine in isolation if the operating system path changes underneath it. The Linux team cannot treat SQL Server as just another package if Always On, Full-Text Search, PolyBase, SQL Agent, or backup tooling adds database-specific dependencies. The supportable design is the one where OS distribution, SQL build, HA topology, and recovery procedure are tested together.
The practical takeaway is straightforward: before moving SQL Server on Linux to 2025, decide the supported distribution target first. Inventory any SLES-hosted SQL workloads, confirm whether they stay on older SQL versions or move to RHEL or Ubuntu, rebuild automation around the new package source, and prove restore and failover behavior before production cutover. SQL Server 2025 on Linux is still a database decision, but in 2026 it is also clearly an operating-platform decision.