Job Summary • Administer, maintain, and support physical and virtual Windows, Linux/UNIX, and Active Directory server environments. • Install, configure, patch, upgrade, and maintain operating systems, applications, and enterprise services. • Monitor system and network performance and troubleshoot hardware, software, connectivity, and operational issues. • Provide Tier II/III technical support, including workstation deployment, peripheral support, user account administration, and technical training. • Manage user accounts, permissions, privileged access, and authentication services. • Administer network infrastructure including routers, switches, firewalls, encryptors, LAN/WAN connectivity, and copper/fiber cabling systems. • Maintain network documentation, configurations, port assignments, uptime, traffic, and network health. • Support cybersecurity operations, including RMF requirements, security controls, vulnerability assessments, continuous monitoring, and ATO compliance. • Respond to cybersecurity incidents, malware infections, and classified spillage events. • Perform backup, recovery, contingency, and disaster recovery procedures. • Coordinate with vendors, government stakeholders, and support organizations to resolve technical issues. • Support system modernization, technology evaluations, lifecycle replacement, testing, and implementation of new technologies. • Prepare technical briefings, reports, recommendations, and analysis for leadership and stakeholders. • Develop and maintain SOPs, configuration records, troubleshooting guides, and technical documentation. • Identify process improvements, automation opportunities, and operational efficiencies. Qualifications • Active DoD Top Secret Clearance required. • 8+ years of enterprise IT systems administration experience. • Experience with Windows/Linux servers, virtualization, Active Directory, and network infrastructure. • IAT Level II certification or higher under DoD 8570/8140. • Experience with Microsoft Windows Server, Active Directory, Group Policy, and VMware vSphere/ESXi. • Knowledge of enterprise network management, monitoring, and troubleshooting. • Ability to install, configure, maintain, and troubleshoot network, server, and communications technologies.