IT System Administrator
CTC Global · Irvine, CA
SUMMARY
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
- Administer and maintain virtual environments (VMware / Hyper-V)
- Administer and maintain 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
Network & Infrastructure Support
- 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
OT / Industrial Systems Support
- Support and maintain systems connected to PLCs, SCADA, and HMI environments
- Support and maintain 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
Backup, Recovery & Business Continuity
- Manage backup solutions for servers, systems, and critical OT data
- Develop and maintain disaster recovery procedures
- Participate in DR testing and incident recovery
Monitoring, Performance & Optimization
- Monitor system and infrastructure performance across IT and OT environments
- Identify bottlenecks, risks, and availability issues
- Implement performance tuning and system improvements
Security & Compliance
- Apply patches, updates, and security baselines to systems
- Support vulnerability remediation and audit requirements
- Ensure compliance with corporate policies and regulatory standards
Documentation & Standards
- Maintain documentation for systems configurations
- Maintain documentation for network diagrams and dependencies
- Maintain documentation for OT system integrations and workflows
- Follow ITIL processes (change, incident, problem management)
Cross-Functional Collaboration
- Work closely with IT Infrastructure and Security teams
- Work closely with Manufacturing / Production teams
- Work closely with Automation and Controls Engineers
- Provide guidance on system and infrastructure requirements for projects
Support & Continuous Improvement
- Support Helpdesk escalation tickets
- Identify automation opportunities and improve operational efficiency
- Mentor junior staff and promote best practices
Qualifications
Education
- Bachelor’s degree in Computer Science, Information Systems, or equivalent experience
Certifications (Preferred)
- 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
- 7+ years of experience in Infrastructure / Network Support
- OT / Manufacturing environment experience preferred
- Experience supporting multi-site or global operations is a plus
Technical Skills
Systems & Infrastructure
- Windows Server, Active Directory, Group Policy
- Virtualization (VMware / Hyper-V)
- Microsoft 365 / Azure
- Backup and recovery platforms
Networking
- TCP/IP, DNS, DHCP, VLANs
- Firewall and VPN technologies
- Wireless and enterprise networking
OT / Industrial Systems (Preferred)
- Experience with PLC-connected systems
- Experience with SCADA / HMI platforms
- Experience with industrial protocols (Aveva, Modbus, OPC, Ethernet/IP)
- Understanding of IT segmentation and secure ICS environments
Key Competencies
- 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
