Linux System Administrator

Leidos LLC; Huntsville (AL); On-site; USD 92,000 - 167,000; Full time

Job summary

Leidos-Dynetics is seeking a Linux Systems Administrator to ensure secure, compliant operation of information systems at the Huntsville site. You'll perform system design, maintain Linux/Windows endpoints, and coordinate with the IA team to meet DoD standards.

The role requires TS/SCI clearance with polygraph and DoD IAT II certification, plus hands-on experience across networks and security tools. Ideal candidates will have a strong background in vulnerability management, STIGs, and privileged

Qualifications

• Bachelor's degree or equivalent experience and 8+ years of System Administration experience.
• 4+ years administering Linux operating systems.
• Must hold DoD TS/SCI with ability to obtain Poly clearance (priority for active polygraph).
• DoD 8570 / 8140 IAT Level II certification (Security+ CE, CCNA Security, CySA+, GICSP, GSEC, CND, SSCP).
• Ability to manage multiple networks in a dynamic environment.
• Familiarity with RMF requirements for Windows, Linux, and network devices.
• Strong written and verbal communication skills.

Responsibilities

• Perform system design and new hardware/software implementation.
• Maintain Linux, Network devices, and Windows endpoints.
• Keep information systems compliant and aligned with DoD standards.
• Coordinate with the Information Assurance team to meet compliance.
• Manage privileged access management.
• Ensure proper marking, handling, and storage of classified materials.
• Maintain baseline configuration of information systems.
• Lead projects across the Area of Responsibility.
• Adopt new technologies and train staff to stay compliant.
• Maintain a robust virtual and physical environment.

Skills

Linux administration

Networking

Windows administration

Vulnerability scanning

Security STIGs

Communication skills

Stakeholder collaboration

Privileged access management

Compliance

Risk Management Framework

Education

Bachelor's degree or equivalent experience

DoD 8570/8140 IAT Level II certification

Tools

RHCSA

Ansible

TACLANE

Security+ CE

CCNA Security

CySA+

GICSP

GSEC

CND

SSCP

Job description

Are you interested in advancing your career in IT System Administration? Leidos-Dynetics, within our Corporate Information Security Office (CISO and reporting through our Digital Modernization sector, is seeking a motivated Linux Systems Administrator to become a part of our team. In this role, you will be responsible for ensuring the secure and efficient operation of various information systems. This includes conducting regular vulnerability scans and implementing Security Technical Implementation Guides (STIGs) to maintain regulatory compliance. Mastery of Linux, networking, and Windows is critical for success in our diverse technological environment. Furthermore, effective communication with stakeholders and collaboration with cross-sector teams will be necessary to achieve organizational objectives. At Leidos-Dynetics, we recognize the value of having a high-performing workforce and are committed to providing opportunities for employees by encouraging career growth and movement across the enterprise. We view career development as a partnership between employees, managers, and the company with a focus on building skills and experiences through internal mobility. To support career development, we offer a variety of resources in addition to training and educational opportunities within an inclusive environment.

Location: All work will be performed on-site in our Huntsville office.

Clearance: You must hold a current DoD Top Secret/SCI clearance with ability to obtain Polygraph. NOTE: Those with a current TS/SCI and Polygraph will be given priority consideration.

What We Value:

• We're not just looking for expertise; we value a positive attitude, adaptability to changing priorities, and a commitment to delivering results. Our ideal candidate is a reliable troubleshooter, adept at handling multiple priorities with excellent coping skills. Whether working independently or collaboratively, you're self-managed and customer-focused.

Key Responsibilities:

• Perform system design and new hardware/software implementation.
• Maintain Linux, Network devices, and Windows endpoints.
• Keep information systems compliant and aligned with DOD standards.
• Coordinate with the Information assurance team to meet compliance.
• Manage privileged access management.
• Ensure the proper marking, handling, and storage of classified materials.
• Maintain Baseline configuration of various information systems.
• Work on multiple projects, leading projects that fall within the Area of responsibility.
• Adopt new technologies and ensure that all staff members are trained to keep them compliant.
• Maintain a robust virtual and physical environment.

Experience and Skills:

• Bachelors degree coupled with a minimum of eight (8) years of System Administration experience. Equivalent relevant work experience may be considered in lieu of a degree.
• Minimum of 4+ years administering Linux operating systems.
• Must currently hold minimum DoD TS/SCI with ability to obtain Poly clearance; those holding active polygraph will be given priority consideration.
• DoD Directive 8570 / 8140 Information Assurance Technical (IAT) Level II certification. (Security+ CE, CCNA Security, CySA+, GICSP, GSEC, CND, SSCP)
• Demonstrate ability to manage multiple networks in a dynamic, demanding environment.
• Possess familiarity with Risk Management Framework requirements for Windows Systems, Linux Systems, and network Devices.
• Demonstrate ability to interface effectively with security agencies, customers, and management.
• Strong written and verbal communication skills.

Preferred Qualifications:

• Active TS/SCI with Polygraph.
• Previous experience maintaining networks in classified environments.
• Understanding of network concepts, Type 1 encryption devices (e.g., TACLANE), and cybersecurity tools.
• Knowledge of VOIP.
• Experience with Ansible.
• RHCSA (Red Hat Certified System Administrator)

If you're looking for comfort, keep scrolling. At Leidos, we outthink, outbuild, and outpace the status quo — because the mission demands it. We're not hiring followers. We're recruiting the ones who disrupt, provoke, and refuse to fail. Step 10 is ancient history. We're already at step 30 — and moving faster than anyone else dares.

Original Posting: August 17, 2026 For U.S. Positions: While subject to change based on business needs, Leidos reasonably anticipates that this job requisition will remain open for at least 3 days with an anticipated close date of no earlier than 3 days after the original posting date as listed above.

Pay Range: Pay Range $92,300.00 - $166,850.00 The Leidos pay range for this job level is a general guideline only and not a guarantee of compensation or salary. Additional factors considered in extending an offer including (but are not limited to) responsibilities of the job, education, experience, knowledge, skills, and abilities, as well as internal equity, alignment with market data, applicable bargaining agreement (if any), or other law.

Leidos Leidos is an industry and technology leader serving government and commercial customers with smarter, more efficient digital and mission innovations. Headquartered in Reston, Virginia, with 47,000 global employees, Leidos reported annual revenues of approximately $17.2 billion for the fiscal year ended January 2, 2026. For more information, visit www.Leidos.com.

Pay and Benefits Pay and benefits are fundamental to any career decision. That's why we craft compensation packages that reflect the importance of the work we do for our customers. Employment benefits include competitive compensation, Health and Wellness programs, Income Protection, Paid Leave and Retirement. More details are available here.

Securing Your Data Leidos will never ask you to provide payment-related information at any part of the employment application process. And Leidos will communicate with you only through emails that are sent from a Leidos.com email address. If you receive an email purporting to be from Leidos that asks for payment-related information or any other personal information, please report the email to [e-mail].

Commitment and Diversity All qualified applicants will receive consideration for employment without regard to sex, race, ethnicity, age, national origin, citizenship, religion, physical or mental disability, medical condition, genetic information, pregnancy, family structure, marital status, ancestry, domestic partner status, sexual orientation, gender identity or expression, veteran or military status, or any other basis prohibited by law. Leidos will also consider for employment qualified applicants with criminal histories consistent with relevant laws.