About Us

We are a French company specializing in the development and operation of critical computing infrastructures, with a focus on hyperdense data centers dedicated to artificial intelligence.

Sesterce was built on a clear conviction: Europe needs sovereign, high-performance, and decarbonized AI infrastructure. In full growth mode, our mission is to design, build, and operate next-generation computing campuses across France and internationally. Our solutions power the most demanding AI workloads for leading clients in the industry.

To strengthen our Infrastructure team, we are looking for a methodical, autonomous, and technically sharp System Administrator.

Your Responsibilities

Systems Administration

• Deploy, configure, and maintain Linux servers (RHEL, Ubuntu, Debian) in production
• Manage bare-metal servers and GPU nodes (NVIDIA H100/B200)
• Automate provisioning with Ansible, Terraform, and PXE/iPXE
• Manage system lifecycle (BIOS/UEFI, firmware updates, hardware replacement coordination)

Storage & Networking

• Administer storage systems (Ceph, NFS, iSCSI, NVMe-oF)
• Configure and maintain network interfaces and bonding (LACP, SR-IOV)
• Manage DNS, DHCP, NTP, and internal services
• Configure and maintain backup and recovery systems

Monitoring & Incident Response

• Deploy and maintain monitoring stacks (Prometheus, Grafana, AlertManager, Zabbix)
• Define alerting rules and SLA dashboards
• Respond to system incidents; participate in on-call rotations
• Perform root cause analysis and post-mortem documentation

Security & Compliance

• Harden Linux systems (CIS Benchmarks, SELinux/AppArmor, kernel tuning)
• Manage user accounts, SSH keys, and sudo policies
• Apply security patches and vulnerability remediation
• Contribute to SOC2/ISO 27001 compliance efforts

Documentation

• Maintain up-to-date infrastructure documentation (runbooks, network diagrams, CMDB)
• Contribute to internal knowledge base and operational procedures

Your Profile

Education & Experience

• Bachelor's in Computer Science, networks, or equivalent
• 3+ years in Linux system administration in production environments

Technical Skills

• Expert: Linux (RHEL/Ubuntu/Debian), Bash scripting
• Proficient: Ansible, Terraform, Prometheus/Grafana
• Knowledge: storage systems (Ceph, NFS, NVMe), networking (VLANs, bonding, SR-IOV)
• Experience with GPU servers (NVIDIA) is a strong plus

Personal Qualities

• Autonomous, methodical, and available for on-call duties
• Rigorous documentation habits and a strong sense of service continuity

Languages

• English: professional level required
• French: fluent

Why Join Us?

• Operate the systems backbone of one of Europe's most advanced GPU and HPC infrastructures
• Manage bare-metal GPU servers (H100/B200) powering real AI workloads in production
• A purely technical role with full ownership and real impact on infrastructure reliability
• A tight-knit, demanding, and passionate team where every contribution matters
• Competitive package: salary based on profile, health insurance, transportation

How to Apply

• Send your application (resume + cover letter) to:hr@sesterce.com
• Please use the reference "SYS-ADMIN-MRS" in the subject line of your email.