CERN is transitioning 2200 accelerator control computers from RHEL to Debian by the end of 2026.
At MiniDebConf Winterthur, Conseil Européen pour la Recherche Nucléaire/ European Organization for Nuclear Research (CERN) engineers Federico Vaga and Nikos Tsipinakis detailed the organisation’s plan for migrating over 2200 particle accelerator control computers and embedded systems from Red Hat Enterprise Linux (RHEL) to Debian 13 (‘Trixie’) by the end of this year.
The primary trigger was Red Hat’s progressive tightening of compiler microarchitecture baselines. CERN’s accelerator infrastructure manages more than 2200 specialised front-end computers and 17,000 embedded devices. When Red Hat builds RHEL, it picks a minimum central processing unit (CPU) generation the software will run on. RHEL 9’s upstream microarchitecture mandates already obsolete CERN’s oldest boards, the kind running chips like Intel’s legacy Core 2 Duo and Ivy Bridge, which comprise about 47 percent of their fleet. Staying on RHEL would force CERN to replace functional legacy hardware and redesign custom circuit boards at an estimated cost of CHF 5.4 million (US$6.58 million).
CERN selected Debian because it supports older 64-bit hardware, offers a massive software library, and works well with industrial tools. Also, built-in real-time updates in the Linux kernel allow Debian to run time-sensitive systems without needing specialized software.
The accelerator control group is targeting Debian 13 (‘Trixie’) with the completion of the migration slated for the fourth quarter of 2026. Both CERN engineers emphasised that the migration is strictly scoped to accelerator control hardware; in other words, CERN’s petabyte-sized compute farms and Tier-0 grid infrastructure will continue on AlmaLinux and RHEL.
