REQ# GDI_17_019 and GDI_17_020: Minimum 12 years' total experience with C4I systems with specific focus on administration and sustainment of Red Hat Enterprise Linux (RHEL) systems. Will maintain the lab and production environment except during approved testing events. Will develop and maintain system drawings of the current environment and update based on testing events and configuration changes. Will troubleshoot field systems, test new systems/configurations in a lab environment, and actively participate in technical meetings. Will ensure systems are compliant with DISA STIGs in addition to perform ACAS scans. Will track and prioritize all submitted trouble tickets, help desk calls, and CASREPS. Candidate will communicate technical knowledge and direction through briefs, requirements specifications, system design documentation, test plans, and reports. Candidate will have privileged access and must meet Cybersecurity Workforce (CSWF) Information Assurance Technician (IAT) Level II requirements. Must have CompTIA Linux+ and Security+ CE certifications at a minimum. Candidate must be a U.S. citizen, and have an active TS clearance with SCI eligibility.