Linux System Administrator

Job Category: Information Technology | Full‑time | Location: CACI facility, Sterling, VA | Clearance: Active TS/SCI with polygraph | Travel: Up to 10% local

About the role

CACI’s National Mission Systems (NMS) group is seeking a highly motivated Linux Systems Administrator to support mission‑critical environments by ensuring secure, reliable, and scalable infrastructure across cloud and bare‑metal systems. The role is central to delivering a secure, resilient ground infrastructure that houses mission‑critical space‑based applications and shapes how national security missions are executed from space to ground using modern deployment approaches and emerging technologies.

Responsibilities

• Ensure optimal performance, scalability, and security of all infrastructure environments.
• Perform Linux system administration and support multi‑environment infrastructure (Dev/Test/Prod).
• Apply security patches, OS upgrades, and maintain system integrity and compliance.
• Design, configure, and maintain LAN/WAN/VPN network infrastructure.
• Monitor network performance, troubleshoot issues, and collaborate with external communications teams as needed.
• Conduct hardware deployments, installation, configuration, and troubleshooting.
• Support CI/CD pipeline environments and collaborate with DevSecOps teams to ensure availability and readiness.
• Manage containerized environments and automated infrastructure (Docker, Kubernetes, Ansible, Puppet).
• Create, manage, and automate cloud and virtual machine infrastructure via repeatable scripts and automation playbooks.
• Troubleshoot issues involving servers, user systems, storage, and network connectivity using advanced diagnostic techniques.
• Ensure compliance with government IT and security policies, including cross‑security domain requirements.
• Collaborate with architects, technical leads, developers, testers, security teams, and other program stakeholders.
• Support new infrastructure projects and modernization initiatives involving microservices, containers, and cloud‑native architectures.
• Maintain configuration documentation for assigned systems and provide subject‑matter expertise during system design and development.

Qualifications

• Active TS/SCI security clearance with polygraph.
• Bachelor’s degree in Computer Science, Information Technology, or a related field.
• 7+ years of experience in infrastructure, network architecture, and development environments.
• Proven experience with Linux system administration.
• Experience with Development/Test and Production environments.
• Strong analytical and investigative skills for resolving complex problems.
• Familiarity with information security and compliance with government policies.
• Proficiency in cloud platforms (AWS, Azure, Google Cloud) and related certifications highly desired.
• Strong knowledge of network protocols and security (TCP/IP, VPN, firewalls).
• Experience with CI/CD tools and version control systems (Git).
• Active CISSP or Security+ certification (or comparable information‑security certifications).
• Full systems lifecycle experience.
• Experience with DevOps processes and tools.
• Experience providing customer support as part of infrastructure, platform, or help‑desk teams.
• Recognized subject‑matter expert in systems administration.
• Working knowledge of Puppet, Satellite, IPA, Nagios, and NetApp.
• Strong problem‑solving skills for complex and undefined issues.
• Innovative mindset with a track record of making significant improvements to systems or products.

Pay

Proposed Salary Range: $103,800 – $218,100. Final compensation may vary based on geographic location, contract labor categories, prior experience, specific skills, education, and certifications.

Benefits

CACI offers a competitive mix of benefits designed to support and protect employees and their families, including healthcare, wellness programs, financial and retirement options, family support, continuing education, and flexible time‑off benefits.

What You Can Expect

A culture of integrity, trust, and continuous growth. Employees enjoy autonomy, flexible time‑off, robust learning resources, and the opportunity to contribute to critical national missions while advancing their own careers.