Administer and secure enterprise IT and OT environments across sites, supporting Windows Server, virtualization, networking, cloud (Azure/M365), PLC/SCADA integrations, backups, DR, segmentation and Zero Trust initiatives. Provide Tier 2/3 escalation, network/OT troubleshooting, monitoring, documentation, compliance support, and collaborate with infrastructure, security, and manufacturing teams to maintain production uptime.
SUMMARY
ESSENTIAL DUTIES AND RESPONSIBILITIES:
IT Systems Administration (Enterprise)
The IT Systems Administrator is responsible for the administration, maintenance, and security of both IT (enterprise systems) and OT (manufacturing/industrial systems) environments across all locations.
This role bridges enterprise IT and operational technology, ensuring reliable, secure, and scalable integration between servers, networks, cloud platforms, and manufacturing systems (PLCs, SCADA, HMIs).
The position is critical in supporting business operations, production uptime, cybersecurity initiatives (including Zero Trust), and IT convergence strategies.
ESSENTIAL DUTIES AND RESPONSIBILITIES:
IT Systems Administration (Enterprise)
- Administer and maintain:
- Windows Server environments, Active Directory, DNS, DHCP
- Virtual environments (VMware / Hyper-V)
- Cloud services (Azure / M365)
- Manage system performance, availability, and patching
- Support identity and access management (IAM) and Group Policy
- Provide Tier 2/3 escalation support for infrastructure issues
- Support LAN, WAN, VPN, wireless, and cloud network connectivity
- Assist with configuration and troubleshooting of network devices (switches, firewalls, APs)
- Monitor infrastructure performance and availability
- Collaborate with network engineering on upgrades and optimization
- Support and maintain systems connected to:
- PLCs, SCADA, and HMI environments
- Industrial control systems (ICS) within manufacturing sites
- Ensure reliable system and network communication for production equipment
- Assist in troubleshooting production-impacting system issues
- Coordinate with manufacturing, automation, and controls teams
IT Integration & Security
- Support secure integration between IT and OT environments
- Implement system-level and network-level segmentation controls
- Contribute to Zero Trust Architecture initiatives
- Ensure secure authentication, access controls, and system hardening across environments
- Manage backup solutions for servers, systems, and critical OT data
- Develop and maintain disaster recovery procedures
- Participate in DR testing and incident recovery
- Monitor system and infrastructure performance across IT and OT environments
- Identify bottlenecks, risks, and availability issues
- Implement performance tuning and system improvements
- Apply patches, updates, and security baselines to systems
- Support vulnerability remediation and audit requirements
- Ensure compliance with corporate policies and regulatory standards
- Maintain documentation for:
- Systems configurations
- Network diagrams and dependencies
- OT system integrations and workflows
- Follow ITIL processes (change, incident, problem management)
- Work closely with:
- IT Infrastructure and Security teams
- Manufacturing / Production teams
- Automation and Controls Engineers
- Provide guidance on system and infrastructure requirements for projects
- Support Helpdesk escalation tickets
- Identify automation opportunities and improve operational efficiency
- Mentor junior staff and promote best practices
Education
- Bachelor’s degree in Computer Science, Information Systems, or equivalent experience
- Microsoft (Azure / Windows Server) certifications
- CCNA or equivalent networking certification
- Security+ or equivalent
- OT / ICS certifications (a plus)
Professional Experience
- 7+ years of experience in:
- Systems Administration
- Infrastructure / Network Support
- OT / Manufacturing environment experience preferred
- Experience supporting multi-site or global operations is a plus
Systems & Infrastructure
- Windows Server, Active Directory, Group Policy
- Virtualization (VMware / Hyper-V)
- Microsoft 365 / Azure
- Backup and recovery platforms
- TCP/IP, DNS, DHCP, VLANs
- Firewall and VPN technologies
- Wireless and enterprise networking
- Experience with:
- PLC-connected systems
- SCADA / HMI platforms
- Industrial protocols (Aveva, Modbus, OPC, Ethernet/IP)
- Understanding of IT segmentation and secure ICS environments
- Strong troubleshooting and analytical skills
- Ability to operate across IT and manufacturing environments
- Effective communication across technical and business teams
- Strong documentation and process discipline
- High sense of urgency, especially for production-impacting issues
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