RHEL 8 Linux Systems Administrator – TS/SCI On‑Site

SAIC; El Segundo (CA); On-site; USD 120,001 - 160,000; Full time

Job summary

SAIC in El Segundo, CA is seeking an experienced RHEL 8+ Linux Systems Administrator to support air‑gapped, mission‑critical information systems. You will administer enterprise Linux, implement security hardening, and maintain offline environments in a secure, on-site setting.

The role requires TS/SCI clearance with poly, DoD 8140 certifications, and hands‑on scripting with Bash or Python. You will work with cybersecurity, GRC, and network teams to ensure compliance and effective incident

Qualifications

• Bachelors Degree or five (5) years experience or equivalent.
• Active TS clearance with SSBI/T5 background investigation and ability to obtain SCI/SAP access.
• Willingness to be nominated for access to SAP/SAP programs and polygraph if required.
• DoD 8140 (formerly DoD 8570) certification (e.g. Security+, CISSP, or equivalent).
• Strong documentation process experience.
• 3+ years administering Linux systems in an enterprise setting.
• Hands-on experience with RHEL 8 or later.
• Experience supporting air-gapped, isolated, or high-security information systems.
• Knowledge of system hardening, patching, and offline configuration management.
• Bash or Python scripting proficiency.
• Knowledge of SELinux, systemd, LVM, and networking fundamentals.
• Familiarity with STIGs, CIS benchmarks, or similar.

Responsibilities

• Install, configure, harden, and maintain RHEL 8+ systems across air-gapped environments.
• Perform system patching, repository management, and package deployment offline.
• Develop and maintain baselines, documentation, and configuration standards for security/compliance.
• Monitor performance, troubleshoot issues, and support incident response activities.
• Implement STIGs, CIS benchmarks, and other hardening guidelines as required.
• Secure configuration of services, authentication, logging, auditing, and access controls.
• Coordinate with cybersecurity, network, and GRC teams to ensure ongoing compliance.
• Automate routine tasks using shell scripting, Ansible, or similar tooling.
• Assist with system integration, data transfers, and cross-domain solutions in isolated environments.
• Collaborate across cybersecurity, GRC, and infrastructure teams.
• Demonstrate solid problem-solving skills with a security-first mindset.

Skills

Bash scripting

Python scripting

System hardening

Air-gapped environment experience

Documentation

Security compliance

Troubleshooting

Collaboration

Education

Bachelor's Degree

DoD 8140 Certification

Tools

Ansible

KVM/VMware

Podman

Docker

Kubernetes

SELinux tooling

Job description

SAIC in El Segundo, CA is seeking an experienced RHEL 8+ Linux Systems Administrator to support air‑gapped, mission‑critical information systems. You will administer enterprise Linux, implement security hardening, and maintain offline environments in a secure, on-site setting.

The role requires TS/SCI clearance with poly, DoD 8140 certifications, and hands‑on scripting with Bash or Python. You will work with cybersecurity, GRC, and network teams to ensure compliance and effective incident