Systems & Infrastructure Administrator

About the role

We are seeking a versatile Systems Administrator to architect, deploy, and maintain an isolated, high-fidelity testing environment. In this role, you will build and support a hybrid infrastructure that mirrors enterprise IT and Operational Technology (OT) networks. You will be responsible for configuring core networking, enterprise Windows Active Directory environments, Linux services, and simulated ICS/SCADA components used for cybersecurity training, testing, and red/blue team exercises.

Responsibilities

• Network Engineering & Infrastructure: Design, implement, and maintain virtualized and physical network infrastructure (VLANs, firewalls, routers, VPNs, micro-segmentation, and Purdue Model network architecture).
• Windows Ecosystem Administration: Deploy and manage Active Directory, Domain Controllers, DNS, DHCP, Group Policy (GPOs), Exchange/O365 simulations, and Windows Server/Desktop endpoints across multiple subnets.
• OT/ICS Systems Integration: Deploy, configure, and maintain Operational Technology environments, including SCADA servers, HMIs, PLCs (physical or emulated), and industrial protocols (Modbus, DNP3, Ethernet/IP, IEC 60870-5-104).
• Linux Systems Administration: Provision and maintain Linux servers (RHEL, Ubuntu, Debian) hosting supporting range services, database engines, web applications, and security monitoring tools (e.g., SIEM, IDS/IPS).
• Testing Management & Automation: Utilize virtualization platforms (VMware vSphere/ESXi, Proxmox, Hyper-V) and infrastructure-as-code (Terraform, Ansible, Packer) to quickly deploy, snapshot, reset, and tear down training range scenarios.

Requirements

• 5+ years of hands-on experience in Systems Administration, Network Engineering, and Windows Support.
• Strong proficiency in Windows Server Administration (Active Directory, GPO, PowerShell) and Linux Administration (Bash scripting, service management).
• Solid understanding of routing, switching, firewall configuration, network packet analysis (Wireshark), and industrial network segmentation.
• Familiarity with OT/SCADA concepts, HMI software, PLC communication protocols, and industrial security standards (NIST SP 800-82, IEC 62443).
• Experience managing hypervisors (VMware vSphere/ESXi, KVM, Proxmox) and containerization platforms (Docker).

Qualifications

• Relevant certifications: CompTIA Linux+, MCSA/MCSE, CCNA, GICSP (Global Industrial Cyber Security Professional), or GRID.
• MSFT Certifications