System Administrator
US$115,000 – US$135,000 / yr base salary
Posted 2 Oct 2026
Advertised as “1773 - System Administrator”
BranchFactor Summary
The original posting with the fluff stripped out
- Expected experience
- 3–7 yrs
- Management level
- Individual contributor
- Contract
- Full-time
- Visa sponsorship
- Offered
| Base salary | US$115,000 – US$135,000 / yr |
|---|
CertificationsSecurity+
Field of studyInformation Technology (or related)
Study levelBachelor's
CertificationsRHCSA, Network+, Linux+, Server+
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.