CERN Transitioning To Debian After Being A Longtime RHEL Institution

CERN, the European Organization for Nuclear Research, besides being well known for its Large Hadron Collider (LHC) is known among longtime Linux users as a RHEL/CentOS shop. CERN formally even co-maintained the Scientific Linux RHEL derivative with other educational/research institutions in the past. So to much surprise now, CERN is transitioning to Debian Linux. CERN shared the big news at the MiniDebConf that took place in Winterthur, Switzerland this past weekend. CERN had used their RHEL-derived Scientific Linux for about a decade prior to moving to CentOS in 2015. Now after a decade with CentOS, they are moving on and leaving the RHEL pathway and going for Debian. CERN engineers had considered moving to CentOS Stream as a more natural pathway but ultimately they say "the straw that broke the camel's back" to abandon Red Hat Enterprise Linux was the "-march=x86-64-v2" compiler flag default as "forced obsolescence" for old hardware. Among the challenges they have faced though in their Debian on-boarding is the lack of standard tooling for automated building and publishing of packages - a lot of gaps in the official tooling. There are also a number of tools not supporting multiple versions of the same packages. CERN is planning by the end of 2026 to have all 2,200+ of their industrial computers and embedded systems running Debian 13. Those wishing to learn more can see this video presentation (AV1 WebM) from the MiniDebConf.