System Administrator; BE-CSS-ISALD

Introduction

Are you a skilled and experienced System Administrator and Computing Engineer? Do you want to contribute to the unique challenge of making all CERN particle accelerators function efficiently and synchronised? Join CERN's Controls Software & Services group to work on the computing infrastructure needed to run the largest particle physics laboratory in the world. Take part!

The 24/7 availability of core control system services is critical to the surveillance and operation of CERN's particle accelerators, enabling the organisation to fulfil its central mission. To ensure robustness and scalability, these services are being migrated to a new on‑premises Kubernetes infrastructure backed by modern network storage and Dev Ops technologies.

Our team helps make this success through the development and evolution of this computing infrastructure, a core element of the accelerator complex controls. You will have the opportunity to contribute and influence the evolution of this complex and challenging infrastructure, imprinting your engineering skills on mission‑critical solutions for CERN that will serve for the coming decades.

You will join:

• The BE Department, responsible for beam generation, acceleration, diagnostics, controls and performance optimisation for the LHC and its injector accelerators.
• The CSS Group, responsible for providing and supporting the controls software and infrastructure used to operate and maintain these particle accelerators 24 hours a day.
• The ISA Section, a dynamic and quality‑oriented agile team responsible for CERN Accelerator control system computing infrastructure and system administration.

As a Computing Engineer specialised in System Administration, you will join a passionate team and take an important role in the operation of CERN's accelerator control system infrastructure. You will also participate in numerous strategic projects for the future, involving operating systems, container and orchestration technology.

In particular you will:

• Perform system administration tasks for Linux computers connected to the accelerator control system (control‑room consoles, data‑centre servers, real‑time embedded platforms and virtual machines).
• Communicate with end‑users, understand their needs and help translate them into appropriate solutions.
• Investigate, diagnose and resolve operational problems in collaboration with end‑users ranging from equipment specialists to operations teams.
• Participate actively in the strategic evolution of the accelerator control system infrastructure towards container technology hosted on Kubernetes.
• Provide containerisation mechanisms and tools for software development teams (base images, registry, security aspects).
• Contribute to the planning and migration of the infrastructure from bare metal to a clustered container orchestration platform.
• Advance, improve and upgrade the control system Kubernetes platform and associated services to follow technology evolution and adapt to the needs of users.
• Collaborate closely with engineers from the IT Department responsible for CERN's general IT infrastructure.
• Mentor and supervise junior engineers.

Master's degree or equivalent relevant experience in Computer Science or a related field.

Proven experience in the operation of medium to large‑scale distributed computing infrastructures including:

• High‑performance and high‑availability commercial server platforms.
• Container technologies (Docker, Podman).
• Administration of an on‑premise Kubernetes infrastructure and associated services (e.g. ArgoCD, Hashicorp Vault, Prometheus) with awareness of architectural concerns and lifecycle management, including upgrades and integration with network storage.
• Diagnostic and monitoring solutions for the aforementioned technologies, with awareness of security aspects.
• Configuration‑management tools such as Ansible, Puppet or similar, and a version‑control system such as Git.
• Interest in software failure analysis, diagnostics and validation in a Linux environment.
• Knowledge of Linux operating system support and maintenance.
• Architecture and design of ICT systems: control & data‑acquisition system…