Classified Linux Systems Administrator

Do you thrive in a fast-paced, dynamic classified environment?

Do you want to be empowered to take ownership and stake in the overall engineering and operations of the IT infrastructure?

Are you interested in learning new technologies and creating new IT capabilities?

If so, we're looking for someone like you to apply and join our team at APL!

We are ranked as one of Computerworld 's Top Places to Work in IT for 6 years running, and we are seeking a Linux Systems Administrator to help us protect APL's information technology infrastructure. We are seeking an experienced Linux System Administrator with a background in classified environments to join our team. As a Linux System Administrator, you will play a vital role in maintaining and supporting our classified systems and infrastructure.

As a Linux Systems Administrator, you will...

• Deploy, configure, and maintain Linux-based systems in a high-stakes classified environment, ensuring performance, resilience, and mission continuity.
• Enforce enterprise security posture by implementing DISA STIGs, applying security patches, and proactively addressing vulnerabilities in accordance with DoD cyber compliance standards.
• Provide expert technical support to classified end-users by resolving access issues, installing approved software, and managing user accounts in alignment with security protocols.
• Lead troubleshooting and incident response efforts, rapidly diagnosing system issues and collaborating across IT, cyber, and mission teams to minimize downtime and operational risk.
• Develop and maintain clear, comprehensive documentation including SOPs, configuration baselines, and knowledge articles to support system integrity, audits, and team knowledge transfer.
• Support security inspections, audits, and ATO processes by maintaining compliant configurations and preparing required technical documentation.
• Continuously improve infrastructure reliability and efficiency by identifying automation opportunities, streamlining workflows, and contributing to system lifecycle planning.

You’ll meet our minimum requirements if you have...

• A Bachelor’s degree in Computer Science, Information Technology, a related field or equivalent professional experience.
• At least 4 years of recent hands-on Linux systems administration experience in a classified environment.
• Strong knowledge of Linux distributions such as Red Hat or CentOS.
• Familiarity with virtualization (e.g., VMware, KVM) and containerization tools (e.g., Docker, Kubernetes).
• Experience with scripting to automate manual tasks.
• Understanding of Layer 2 networking and associated troubleshooting.
• Experience applying Security Technical Implementation Guides (STIGs) to systems and devices.
• Strong communicator and effective collaborator, capable of bridging gaps between technical teams and non-technical stakeholders.
• Ability to meet and demonstrate intermediate DoD 8140.03 Cyberspace Workforce Qualification and Management Program requirements through training and/or certifications (e.g., Security or equivalent/higher).
• An active Secret security clearance, and the ability to obtain a Top-Secret clearance.

You’ll go above and beyond if you also have...

• A Master’s degree in Information Systems/Technology, Cybersecurity, Computer Science, or a related field
• A current Red Hat Certified System Administrator (RHCSA) or higher (e.g., RHCE)
• Experience with configuration management tools such as Ansible, Puppet, or Chef to enforce consistent, secure configurations across enterprise Linux environments
• Experience with automated system provisioning and orchestration using tools like Kickstart, Foreman, Satellite, or Terraform
• Familiarity with compliance automation tools like OpenSCAP, Nessus, or Tenable.sc for vulnerability scanning and reporting
• Experience supporting RMF processes, ATO packages, or security control implementation for classified systems
• Proficiency in scripting languages such as Bash, Python, or PowerShell to automate system maintenance and monitoring tasks
• Experience administering Windows Servers and core services such as Active Directory, DNS, DHCP, and Group Policy in a mixed-platform environment
• Exposure to enterprise monitoring platforms (e.g., Nagios, Zabbix, Prometheus, Grafana)
• Experience deploying and maintaining host-based security tools, endpoint detection, or file integrity monitoring solutions in secure environments
• Familiarity with Zero Trust principles, enclave segmentation, or defense-in-depth architecture
• An active Top Secret security clearance (or higher)

Why Work at APL?

The Johns Hopkins University Applied Physics Laboratory (APL) brings world-class expertise to our nation’s most critical defense, security, space and science challenges. While we are dedicated to solving complex challenges and pioneering new technologies, what makes us truly outstanding is our culture. We offer a vibrant, welcoming atmosphere where you can bring your authentic self to work, continue to grow, and build strong connections with inspiring teammates.

At APL, we celebrate our differences of perspectives and encourage creativity and bold, new ideas. Our employees enjoy generous benefits, including a robust education assistance program, unparalleled retirement contributions, and a healthy work/life balance. APL’s campus is located in the Baltimore-Washington metro area. Learn more about our career opportunities at http://www.jhuapl.edu/careers.

All qualified applicants will receive consideration for employment without regard to race, creed, color, religion, sex, gender identity or expression, sexual orientation, national origin, age, physical or mental disability, genetic information, veteran status, occupation, marital or familial status, political opinion, personal appearance, or any other characteristic protected by applicable law. APL is committed to providing reasonable accommodation to individuals of all abilities, including those with disabilities. If you require a reasonable accommodation to participate in any part of the hiring process, please contact Accommodations@jhuapl.edu.

The referenced pay range is based on JHU APL’s good faith belief at the time of posting. Actual compensation may vary based on factors such as geographic location, work experience, market conditions, education/training and skill level with consideration for internal parity. For salaried employees scheduled to work less than 40 hours per week, annual salary will be prorated based on the number of hours worked. APL may offer bonuses or other forms of compensation per internal policy and/or contractual designation. Additional compensation may be provided in the form of a sign-on bonus, relocation benefits, locality allowance or discretionary payments for exceptional performance. APL provides eligible staff with a comprehensive benefits package including retirement plans, paid time off, medical, dental, vision, life insurance, short-term disability, long-term disability, flexible spending accounts, education assistance, and training and development. Applications are accepted on a rolling basis.

Salary : $90,000 - $230,000