IT System Administrator

CTC Global Corporation; Irvine (CA); On-site; USD 90,000 - 120,000; Full time

Job summary

CTC Global Corporation is seeking an IT Systems Administrator to manage enterprise IT and OT environments across manufacturing sites in Irvine. The role ensures secure, reliable integration of servers, networks, cloud platforms, and industrial systems while supporting production uptime and cybersecurity initiatives.

The ideal candidate will administer Windows Server, AD, virtualization, cloud services, and IAM, with experience in IT-OT collaboration and Zero Trust architecture.

Qualifications

• Bachelor’s degree or equivalent in computer science, information systems, or related field.
• 7+ years in IT Systems Administration or similar roles in enterprise environments.
• Experience with IT/OT convergence, cybersecurity initiatives, and Zero Trust concepts.

Responsibilities

• Administer Windows Server, AD, DNS, DHCP, and group policy.
• Maintain virtualization platforms (VMware/Hyper-V) and cloud services (Azure/M365).
• Support IAM, patch management, and incident escalation (Tier 2/3).
• Manage network connectivity (LAN/WAN/VPN), firewalls, and wireless.
• Assist integration of IT with OT systems (PLCs/SCADA/HMI) and ICS security.
• Develop and test disaster recovery procedures and backups.
• Document configurations and network diagrams; follow ITIL processes.

Skills

Windows Server

Active Directory

VMware

Hyper-V

Azure

M365

IAM

Group Policy

Networking

Zero Trust

Documentation

Education

Bachelor’s degree in CS/IS or equivalent

Tools

VMware

Hyper-V

Azure

M365

DNS/DHCP

Job description

SUMMARYThe 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, DHCPVirtual environments (VMware / Hyper-V)Cloud services (Azure / M365)Manage system performance, availability, and patchingSupport identity and access management (IAM) and Group PolicyProvide Tier 2/3 escalation support for infrastructure issuesNetwork & Infrastructure SupportSupport LAN, WAN, VPN, wireless, and cloud network connectivityAssist with configuration and troubleshooting of network devices (switches, firewalls, APs)Monitor infrastructure performance and availabilityCollaborate with network engineering on upgrades and optimizationOT / Industrial Systems SupportSupport and maintain systems connected to:PLCs, SCADA, and HMI environmentsIndustrial control systems (ICS) within manufacturing sitesEnsure reliable system and network communication for production equipmentAssist in troubleshooting production-impacting system issuesCoordinate with manufacturing, automation, and controls teamsIT Integration & SecuritySupport secure integration between IT and OT environmentsImplement system-level and network-level segmentation controlsContribute to Zero Trust Architecture initiativesEnsure secure authentication, access controls, and system hardening across environmentsBackup, Recovery & Business ContinuityManage backup solutions for servers, systems, and critical OT dataDevelop and maintain disaster recovery proceduresParticipate in DR testing and incident recoveryMonitoring, Performance & OptimizationMonitor system and infrastructure performance across IT and OT environmentsIdentify bottlenecks, risks, and availability issuesImplement performance tuning and system improvementsSecurity & ComplianceApply patches, updates, and security baselines to systemsSupport vulnerability remediation and audit requirementsEnsure compliance with corporate policies and regulatory standardsDocumentation & StandardsMaintain documentation for:Systems configurationsNetwork diagrams and dependenciesOT system integrations and workflowsFollow ITIL processes (change, incident, problem management)Cross-Functional CollaborationWork closely with:IT Infrastructure and Security teamsManufacturing / Production teamsAutomation and Controls EngineersProvide guidance on system and infrastructure requirements for projectsSupport & Continuous ImprovementSupport Helpdesk escalation ticketsIdentify automation opportunities and improve operational efficiencyMentor junior staff and promote best practicesEducationBachelor’s degree in Computer Science, Information Systems, or equivalent experienceCertifications (Preferred)Microsoft (Azure / Windows Server) certificationsCCNA or equivalent networking certificationSecurity+ or equivalentOT / ICS certifications (a plus)Professional Experience7+ years of experience in:Systems AdministrationInfrastructure / Network SupportOT / Manufacturing environment experience preferredExperience supporting multi-site or global operations is a plusTechnical SkillsSystems & InfrastructureWindows Server, Active Directory, Group PolicyVirtualization (VMware / Hyper-V)Microsoft 365 / AzureBackup and recovery platformsNetworkingTCP/IP, DNS, DHCP, VLANsFirewall and VPN technologiesWireless and enterprise networkingOT / Industrial Systems (Preferred)Experience with:PLC-connected systemsSCADA / HMI platformsIndustrial protocols (Aveva, Modbus, OPC, Ethernet/IP)Understanding of IT segmentation and secure ICS environmentsKey CompetenciesStrong troubleshooting and analytical skillsAbility to operate across IT and manufacturing environmentsEffective communication across technical and business teamsStrong documentation and process disciplineHigh sense of urgency, especially for production-impacting issues