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About this 1773 - System Administrator role at Sigma Defense

Sigma Defense · Onsite · March Air Reserve Base, California, United States

Sigma Defense is seeking a System Administrator to join our team at March Air Reserve Base. This position plays a key role in maintaining secure Department of War information systems by administering Windows and Red Hat Enterprise Linux (RHEL) environments, performing routine maintenance and patching, and ensuring reliable system operations. The Systems Administrator works closely with the engineering and cybersecurity teams to maintain secure, stable, and mission-ready infrastructure supporting Department of War operations.

Equal Opportunity Employer/Veterans/Disabled: Sigma Defense Systems is an Equal Opportunity Employer. All qualified applicants will receive consideration for employment without regard to race, color, religion, sex, sexual orientation, gender identity, national origin, or protected veteran status and will not be discriminated against on the basis of disability.

Requirements

  • 3-7 years of relevant experience.
  • Experience administering Windows Server and/or RHEL systems.
  • Experience installing, configuring, maintaining, and troubleshooting server operating systems.
  • Experience with virtualization technologies such as VMware ESXi.
  • Experience performing operating system patching, maintenance, and lifecycle support.
  • Basic understanding of networking concepts and enterprise infrastructure.
  • Experience supporting secure or air-gapped Department of War environments.
  • Experience with Cross Domain Solution (CDS) technologies.
  • Experience with Full Motion Video (FMV) systems, platforms, or supporting infrastructure.
  • Experience implementing or maintaining DISA Security Technical Implementation Guides (STIGs).
  • Experience maintaining secure Windows and/or RHEL system baselines.
  • Experience administering RHEL in physical or virtualized environments.
  • Experience with storage, backup, and disaster recovery solutions.
  • Must be a U.S. citizen.

Mandatory Certifications:

  • Security+ is required.
  • RHCSA is preferred.
  • Network+ is preferred.
  • Linux+ is preferred.
  • Server+ is preferred.

Computer Programs/Software:

  • Experience with Bash, PowerShell, Ansible, or other scripting and automation tools.

Personnel Clearance Level:

  • Candidate must possess or have the ability to obtain an active TS/SCI security clearance or higher.
  • Clearance may be sponsored for the right candidate.

Education Requirements:

  • Bachelor's degree from an accredited college or university in Information Technology or related field of study.

Essential Job Duties (not all-inclusive):

  • Install, configure, maintain, and troubleshoot Windows and RHEL systems.
  • Perform routine operating system patching, software updates, and system maintenance.
  • Maintain physical and virtual server infrastructure.
  • Configure and maintain user accounts, storage, system services, and server resources.
  • Troubleshoot hardware, operating system, and application issues.
  • Support implementation of DISA STIGs and approved system configuration changes.
  • Maintain system documentation, configuration baselines, and standard operating procedures.
  • Support system backups, recovery operations, and disaster recovery activities.
  • Support secure Cross Domain Solution (CDS) operations and associated system administration activities.
  • Coordinate with cybersecurity and network engineering personnel to implement approved system changes and maintain secure, reliable system operations.
  • Support testing, integration, and implementation of approved hardware and software changes.
  • Monitor system health, investigate operational issues, and resolve problems to maintain system availability and performance.

Salary Range: $115,000 - $135,000 annually.

Benefits

  • Dental and Vision Insurance
  • Medical Insurance to Include HSA, FSA, and DFSA Plans
  • Life and AD&D coverage
  • Employee Assistance Program (EAP)
  • 401(k) Plan with Company Matching Contributions
  • 160 Hours of Paid Time Off (PTO)
  • 12 (Floating) Holidays
  • Educational Assistance
  • Highly Competitive Salary
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How this System Administrator salary compares

This role pays $125,000/yr — in line with the typical range for System Administrator roles.

$78,365 median $116,000 $162,835

Typical range $95,149–$137,500/yr, from 590 comparable System Administrator listings on JobsRadar (pay annualized to USD). See System Administrator salary insights →

About Sigma Defense

Sigma Defense is challenging the defense industry status quo with an innovative approach to delivering JADC2, DevSecOps and C5ISR capabilities to today’s warfighter. We are hiring the best and brightest to be a part of our team that is focused on bringing next generation technology and solutions to market. As a company founded by veterans, we are committed to supporting our service men and women in their next career and we are proud to be recognized as a 2025 HIRE Vets Medallion Award recipient.

Sigma Defense is a new kind of military system integrator: using the field experience of our team and technical expertise of our businesses to translate sophisticated technologies into a tactical communications fabric that keeps warfighters and commands connected, united, confident, and ready for what’s next. From ground to space and the air in between, Sigma Defense’s software-defined communications and supporting development capabilities support key modernization initiatives across every service branch.

We are a team of innovative professionals collaborating in a highly motivating work environment that fosters creativity and independent thinking. The work we do is meaningful and stimulating and our team is working on cutting-edge projects that move the state-of-the-art closer to the people who need them. If you're looking for a challenging, high growth environment with opportunities to lead and deliver solutions that protect and defend our service men and women, we want to speak to you.

See all jobs at Sigma Defense →

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