Senior OT Systems Administrator & Infrastructure Engineer

Nearfield Instruments; Rotterdam; On-site; EUR 65,000 - 90,000; Full time

Job summary

Nearfield Instruments seeks a hands-on Senior Systems Administrator & Infrastructure Engineer to support the OT environment inside our products. You will ensure uptime, security, and maintainability across Windows and Linux servers, virtualization, storage, and network components.

You will troubleshoot cross-layer issues, analyze traffic with Wireshark/tcpdump, and collaborate with Software, Production, Service, and IT teams to resolve complex product problems.

Qualifications

• Around 5 years of hands-on experience in systems administration, infrastructure engineering, OT, industrial automation, or product environments.
• Strong networking skills, including routing, switching, VLANs, DNS, gateways, VPNs, and firewalls.
• Hands-on with Windows Server, including Active Directory, Group Policy, patching, permissions, and security hardening.
• Hands-on with Ubuntu/Linux administration, including services, updates, permissions, networking, and logging.

Responsibilities

• Operate and improve product control systems and infrastructure with a strong focus on uptime, security, recovery, and supportability.
• Troubleshoot complex connectivity, communication, and performance issues across network, operating system, virtualization and storage layers.
• Diagnose and resolve communication issues between servers, control boxes, sensors, machine controllers, and product subsystems.
• Analyze network traffic and communication protocols using tools such as Wireshark, tcpdump and packet captures.
• Support product issues by identifying root causes, separating infrastructure and software problems, and escalating with clear evidence.
• Manage networking components including subnets, routing, VLANs, DNS, gateways, NAT, VPNs, managed switches and firewall rules.
• Build and maintain site-to-site VPNs and remote access solutions.
• Administer Windows Server and Ubuntu/Linux systems used within the product environment.
• Configure, maintain, and troubleshoot virtualization platforms such as Hyper-V, QEMU, VMware, or equivalent technologies.
• Configure and troubleshoot RAID arrays, storage controllers, backup solutions, disaster recovery processes, and data recovery activities.
• Implement and maintain RBAC, Active Directory permissions, service accounts, and least-privilege access models.
• Strengthen security through hardening, patching, access control, secure baselines, vulnerability remediation and structured change management.
• Perform vulnerability assessments, security remediation, malware validation, antivirus validation and security compliance checks.
• Keep documentation, monitoring, backup, and recovery processes up to date.
• Work closely with Software, Production, Service, and IT teams when product issues require cross-functional troubleshooting.
• Participate in incident response and on-call support when needed.

Skills

Networking skills

Windows Server

Ubuntu/Linux

Virtualization

RBAC / access control

Security hardening

Incident handling

Stakeholder collaboration

Tools

Wireshark

tcpdump

Hyper-V

VMware

QEMU

RAID management

Job description

Nearfield Instruments seeks a hands-on Senior Systems Administrator & Infrastructure Engineer to support the OT environment inside our products. You will ensure uptime, security, and maintainability across Windows and Linux servers, virtualization, storage, and network components.

You will troubleshoot cross-layer issues, analyze traffic with Wireshark/tcpdump, and collaborate with Software, Production, Service, and IT teams to resolve complex product problems.