BAE Systems is seeking a highly trained and motivated Principal Closed Area Systems Administrator to lead and manage classified IT infrastructure operations in support of national security missions. This role is pivotal in ensuring the integrity, security, and availability of systems operating within Sensitive Compartmented Information Facilities (SCIFs) or other closed environments. You will serve as the technical lead for IT services, security compliance, and infrastructure readiness across high-impact, mission-critical programs. This position is 100% onsite within a closed, classified area. Some after-hours or weekend support may be required for maintenance windows or incident response. You must be able to lift equipment (up to 40lbs) and work within controlled environments. In this Principal Linux Administrator position you will make impacts in the following ways; - Administer patch management for RHEL-based Linux systems, including vulnerability scanning, patch deployment, and compliance validation. - Install and configure Trellix (McAfee) Linux Agents for endpoint protection and ePO integration. - Deploy and configure Splunk Universal Forwarders on Linux systems; manage log ingestion and index routing. - Reset LDAP BIND credentials within Splunk, ensuring connectivity and access control integration. - Perform VCSA (vCenter Server Appliance) patching and lifecycle operations. - Apply updates to VMware ESXi hosts, ensuring host profile compliance and uptime. - Access and navigate the ESXi Direct Console User Interface (DCUI) for low-level host management. - Perform Exchange operations in a classified environment including user mailbox creation, troubleshooting, and routine maintenance. - Manage and maintain NetApp storage systems, including volumes, snapshots, and secure protocols. - Operate in VMware vSphere environments, including provisioning, performance monitoring, and resource management. - Install, configure, and maintain WSUS (Windows Server Update Services) for enterprise Windows patching. - Maintain comprehensive documentation and contribute to RMF packages and audit readiness. - Collaborate with ISSOs, security staff, and other IT stakeholders to ensure secure, compliant, and high-performing system operations. This position will be posted for at least 5 calendar days. The posting will remain active until the position is filled, or a qualified pool of candidates is identified. Required Skills and Education - Active U.S. Secret Security Clearance and CompTIA Security+ or equivalent DoD 8570 IAT Level II certification - Active U.S. Government Top Secret Clearance with ability to obtain SCI. - 10+ years of experience (7+ years of experience with a degree) as a system administrator. - Strong command of Linux RHEL patching workflows and package management tools (e.g., YUM/DNF). - Experience with Trellix/McAfee agent installation on Linux systems and ePO integration. - Hands-on expertise with Splunk Universal Forwarders, indexers, and LDAP integration. - Experience with VMware infrastructure, including vCenter, VCSA, ESXi, and DCUI access. - Working knowledge of Microsoft Exchange administration. - Familiarity with NetApp management tools and SAN/NAS storage concepts. - Solid experience operating within vSphere environments in mission-critical settings. - Proven ability to configure and manage WSUS for Windows update distribution. Preferred Skills and Education - Active U.S. TS/SCI Security Clearance. - Bachelors Degree in related field / - Experience and proficiency in both Linux and Windows OS - Experience supporting system accreditation efforts (SSP, POA&M, RMF). - Scripting skills (e.g., Bash, PowerShell) for automation and task efficiency. - Familiarity with DISA STIGs, Nessus vulnerability scanning, and cyber compliance frameworks. - Prior experience in secure lab or test bed environments (Lab-in-a-Box, SAP/SAR support)