Linux System Administrator

The Role We are looking for a Linux Systems Administrator to manage the compute infrastructure that supports our AI research and engineering. Your core focus will be bare-metal servers running Ubuntu Linux, NVIDIA GPU systems for high-performance computing (HPC), and helping orchestrate and optimise virtual compute in the cloud. This is a hands-on infrastructure role combining physical server administration with automation and performance troubleshooting. You will help researchers and engineers run workloads reliably, use shared resources efficiently, and choose appropriate on-premises or cloud capacity for their needs. You will work alongside our existing IT Administrator and Ops Team, who own end-user device security. This role focuses on server and compute infrastructure, with shared responsibility for secure operations and ISO 27001 evidence. What You Will Be Doing - Install, configure, patch and harden Ubuntu Linux on bare-metal servers, planning maintenance to minimise disruption. - Manage physical server health, firmware, disks, storage and remote management interfaces; diagnose hardware faults and coordinate repairs. - Configure and maintain NVIDIA GPU drivers, CUDA compatibility and GPU-enabled container runtimes. - Monitor GPU utilisation, memory, temperatures and errors, and troubleshoot performance across compute, storage and networking. - Help manage shared HPC resources, including job scheduling, queues, resource limits and fair access for research and engineering workloads. - Provision and maintain cloud virtual machines and GPU instances, using repeatable configuration and automation. - Help orchestrate workload provisioning, scheduling and teardown across on-premises and cloud environments, taking account of data security and transfer costs. - Optimise cloud compute through right-sizing, utilisation monitoring, automated shutdown of idle resources and cost tracking; use interruptible capacity where workloads can tolerate it. - Maintain server networking, secure remote access, user permissions, backups and tested recovery procedures. - Automate routine administration using Bash, Python and configuration-management or infrastructure-as-code tools. - Maintain monitoring, runbooks, asset records and security evidence, and support incident response and capacity planning. The Stack Core: Linux (Ubuntu, Red Hat, Suse) · Ansible · Bash, Python · systemd · networking (bonding, jumbo frames, ethtool, iperf3) HPC & GPU: Slurm · NVIDIA drivers / CUDA · Docker · NUMA & PCIe affinity · NVMe scratch, NAS/SMB, LUKS Platform: Terraform/Terragrunt · Kubernetes/Helm · AWS (EKS, RDS, S3, Secrets Manager) · MLflow · Harbor · MinIO · OpenVPN Testing & CI: Molecule · ansible-lint/yamllint · pre-commit · GitHub Actions · Prometheus/Grafana Ways of working: Git for everything · idempotent, check-mode-first changes · every change proves it works Requirements - Solid hands-on experience administering Ubuntu Linux servers from the command line, including services, packages, permissions, storage and logs. - Experience managing physical servers and diagnosing hardware, operating-system and resource issues. - Practical experience supporting NVIDIA GPUs on Linux, including driver installation and troubleshooting GPU availability or CUDA compatibility. - Understanding of shared compute workloads and how CPU, GPU, memory, storage and network constraints affect performance. - Working knowledge of networking fundamentals, including TCP/IP, DNS, routing, firewalls, SSH and VPNs. - Experience provisioning and administering virtual machines in a cloud environment such as AWS, Azure or GCP. - Ability to automate routine tasks using Bash or Python, and maintain scripts and configuration in version control. - A disciplined approach to access management, patching, backups, change control and documentation. - Clear communication and the ability to prioritise infrastructure issues with researchers, engineers and colleagues in IT. Nice to Have - Experience with HPC schedulers such as Slurm, or GPU workload orchestration using Kubernetes. - Familiarity with Docker, Apptainer or NVIDIA Container Toolkit. - Experience with Terraform, Ansible, cloud-init or similar provisioning and configuration tools. - Knowledge of multi-GPU or multi-node workloads, NCCL, InfiniBand or high-speed Ethernet. - Experience managing shared or high-performance storage and investigating I/O bottlenecks. - Familiarity with NVIDIA DCGM, Prometheus, Grafana or equivalent monitoring tools. - Experience with cloud cost optimisation, quotas, capacity planning or interruptible compute. - Exposure to ISO 27001, Cyber Essentials or infrastructure operations in regulated environments. Benefits - Ownership of the compute infrastructure supporting real-world AI research and engineering. - Collaboration with our IT, research and engineering teams, with opportunities to deepen your HPC and cloud expertise. - Private healthcare, including Bupa and mental health support. - Flexible working hours and hybrid working around infrastructure requirements. - Private pension with company contribution. - Cycle-to-work scheme and regular team socials. - 34 days annual leave, comprising 25 days, public holidays and your birthday. - A culture that values autonomy, curiosity and getting things done.