Senior Systems Administrator

The Senior Systems Administrator is a hands-on operations and sustainment professional responsible for administering, maintaining, securing, and troubleshooting enterprise virtual infrastructure, virtual desktop services, Windows server platforms, and endpoint security capabilities in secure DoD environments. Minimum five (5) years of enterprise systems administration experience, preferably in a DoD environment. The position emphasizes reliable day-to-day administration, patching, configuration management, vulnerability remediation, service restoration, and technical documentation. The administrator will support VMware-based virtualization, selected VDI services, Trellix Endpoint Security Solutions (ESS), Microsoft Defender for Endpoint (MDE), and Microsoft Defender for Identity (MDI), while coordinating with engineering, cybersecurity, network, and service desk personnel. The candidate must be able to work independently on assigned administrative tasks, escalate issues appropriately, and maintain approved security and configuration baselines.

Functional Responsibility and Required Skills:
• Administer VMware vSphere, ESXi, vCenter, virtual machines, templates, snapshots, and host resources.
• Support VDI desktop pools, images, user access, profiles, sessions, and client connectivity.
• Administer Windows Server systems, services, permissions, patches, logs, and scheduled tasks.
• Perform routine Active Directory and Group Policy administration.
• Install, configure, monitor, and troubleshoot Trellix ESS and ePO components.
• Administer MDE and MDI onboarding, health, alerts, and assigned remediation actions.
• Apply DISA STIGs, security updates, endpoint policies, and approved configuration baselines.
• Remediate assigned vulnerability findings and document completion status.
• Monitor system health, resolve incidents, restore services, and escalate complex issues.
• Support backups, restoration, continuity, and disaster-recovery activities.
• Maintain inventories, SOPs, troubleshooting guides, maintenance logs, and access records.
• Execute approved changes with validation, rollback, and post-change documentation.
• Use PowerShell to streamline routine administration, reporting, and compliance checks.
• Coordinate with cybersecurity, network, engineering, help desk, and government teams.
• Provide technical guidance and knowledge transfer to junior support personnel.

Desired Skills:
• Experience supporting Navy C4I, PMW 790, or comparable classified DoD environments.
• Experience with VMware or Omnissa Horizon, Citrix VDI, or similar platforms.
• Experience with Trellix ePO, ESS policies, agent health, updates, and troubleshooting.
• Experience with MDE, MDI, Microsoft security portals, alert triage, and device health.
• Working knowledge of Active Directory, Group Policy, DNS, DHCP, and certificates.
• Experience with enterprise backup, SAN/NAS, or virtualization storage support.
• Familiarity with ACAS, RMF, DISA STIGs, POA&Ms, and continuous monitoring.
• Practical PowerShell skills for administration and reporting.
• Experience with Jira, Confluence, SharePoint, Git, or similar tools.
• Strong troubleshooting, documentation, communication, and customer-service skills.

Education Requirements:
Bachelor’s degree in Information Technology, Computer Science, Cybersecurity, or a related technical field is desired. Additional relevant systems administration experience and technical training may be considered in lieu of a degree, subject to contract labor category requirements.

Certification Requirements:
• Required: CompTIA Security+ or another certification meeting applicable DoD Cybersecurity Workforce IAT Level II requirements.
• Desired: VMware Certified Professional (VCP), Microsoft role-based certification relevant to Windows Server or Microsoft Security, Trellix certification or training, and/or an enterprise VDI administration certification.

Clearance Requirements:
Must be a U.S. citizen and possess a SECRET clearance at a minimum, with a current SSBI/T5 investigation as required by the position. TS/SCI eligibility or the ability to obtain an elevated clearance is desired.