Senior Systems Administrator; Linux

Amentum is seeking a highly experienced Senior Linux System Administrator to oversee and manage enterprise-level Linux infrastructure in support of U.S. Navy operations within a Department of Defense (DoD) environment. This role requires deep technical expertise in Linux systems, leadership in secure system administration, and a strong working knowledge of Risk Management Framework (RMF) and NIST SP 800-53 controls. The ideal candidate will demonstrate the ability to lead teams, manage complex environments, and ensure cybersecurity compliance across classified and unclassified networks.

• Administer and maintain Red Hat Linux (RHEL) and other Linux-based environments in classified and unclassified environments across Navy networks.
• Implement and maintain RMF security controls and ensure systems are compliant with DISA STIGs and DoD cybersecurity policies.
• Apply and manage patches and updates across all Linux systems in accordance with DoD and Navy patch management policies.
• Manage automated installation methods and system imaging (e.g., SCCM, VMware, Nutanix, Satellite, Ansible)
• Perform system hardening, patching, and vulnerability remediation using tools such as ACAS, ESS, and SCAP.
• Develop and maintain Power Shell scripts for automation of administrative tasks and system configuration.
• Support virtualization platforms (VMware, Hyper‑V) and manage virtual infrastructure lifecycle.
• Collaborate with cybersecurity teams to support ATO packages, POA&Ms, and audit readiness.
• Maintain system documentation, configuration baselines, and standard operating procedures (SOPs).
• Provide mentorship to junior administrators and IT support staff.
• Participate in Change Control Boards (CCBs) and Configuration Management Boards (CMBs).
• Assist with incident response, forensic analysis, and system recovery efforts.
• Support backup and disaster recovery strategies using enterprise tools (e.g., Veeam, Commvault).
• Evaluate and recommend new Linux technologies and DoD‑approved tools to improve system performance and security.
• Perform other duties as assigned.

Lifting: 25 - 50lbs

Positions:
Walking/Standing;
Crawling/Kneeling;
Stooping;
Sitting;
Frequent climbing

Pushing/ Pulling: 25 - 50lbs

Environmental:
Customer Contact;
Extended Work Day;
Confined Work Area;
Office Laboratory;
Field Assignment;
Inclement Weather

• Advance knowledge and certification in both Windows Server and RHEL is considered highly desired
• Proficiency in automation tools and scripting (e.g., Power Shell, Bash, Python)
• VMware/Nutanix certification
• Knowledge/Administration of Trellix, Log Rhythm, and MDE
• Experience with DoD systems and infrastructure

• Knowledge of Cyber Security Methods and Techniques
• Knowledge of DoD IT systems, to include Windows, RHEL, and comprehensive infrastructure concepts

• Bachelor’s degree and 7+ years of System Administration/IT experience

• HS Diploma and 12 years of System Administration/IT experience

* Advance certifications may be substituted for a degree or experience

• DoD 8570/8140 IAT II
• One of the following OS Certifications required
  • Linux
    • Linux+
    • Red Hat Certified System Administrator (RHCSA)

Top Secret security clearance is required with T5 or equivalent (SSBI) investigation level. Applicants selected must be a US Citizen to apply for a Secret Security Clearance. Applicants selected either must currently possess a Secret clearance or will be subject to a government security investigation and must meet eligibility requirements to obtain clearance prior to commencement of employment and maintain a security clearance for access to classified information or Closed/Restricted Areas throughout duration of employment.

The annual starting salary for the position is between $105K - $145K. Factors which may affect starting pay within this range may include geography/market, skills, education, experience and other qualifications of the successful candidate.

Amentum offers the following benefits for this position, subject to applicable eligibility requirements: medical, dental and vision insurance, 401(k)…