Senior Linux Systems Administrator - Top Secret Clearance

The One 23 Group; Herndon (VA); On-site; USD 120,000 - 170,000; Full time

Job summary

The Senior Linux Systems Administrator at The One 23 Group provides Tier II/III administration for Red Hat Enterprise Linux and UNIX environments supporting JSSC Enterprise Services. Based primarily at the Pentagon, this role covers server administration, patching, security compliance, backup coordination, and on-call rotation.

The position requires an active Top Secret clearance, eligibility for SIPRNet access, and the ability to relocate to Site-R within 12 hours for COOP exercises or

Qualifications

• Active Top Secret security clearance with eligibility for SIPRNet access.
• U.S. citizenship required.
• At least 10 years of IT experience supporting complex systems and operations.
• Advanced UNIX/Linux server administration experience (preferably RHEL).
• Expertise in systems administration, architecture, integration, and monitoring.
• Current DoD IAT Level II certifications such as Security+, CySA+, GSEC, GICSP, SSCP, CCNA Security or equivalent.

Responsibilities

• Administer and maintain Red Hat Enterprise Linux and UNIX servers across production, test, and development environments.
• Perform account administration, OS maintenance, monitoring, and troubleshooting.
• Engineer and sustain Linux server hardware, OS, and software for mission-critical environments.
• Test and deploy patches through approved change-control processes.
• Apply DISA STIGs and support vulnerability remediation and security compliance.
• Support backup, disaster recovery, and continuity-of-operations requirements.
• Monitor system health, performance, capacity, and trends.
• Coordinate with government leads, admins, cybersecurity, and external support.

Skills

Top Secret clearance

UNIX/Linux administration

DoD IAT Level II certification

12x5 operations readiness

On-call/COOP readiness

Tools

VMware

Job description

The Senior Linux Systems Administrator at The One 23 Group provides Tier II/III administration for Red Hat Enterprise Linux and UNIX environments supporting JSSC Enterprise Services. Based primarily at the Pentagon, this role covers server administration, patching, security compliance, backup coordination, and on-call rotation.

The position requires an active Top Secret clearance, eligibility for SIPRNet access, and the ability to relocate to Site-R within 12 hours for COOP exercises or