Senior Linux Systems Administrator with Security Clearance

Senior Level | Longmont, CO | $100,000-$158,000 | Active Secret Clearance with Ability to Obtain TS/SCI Caribou Thunder is seeking an experienced Senior Linux System Administrator to join our Systems Administration (SA) Team supporting mission-critical computing environments. This senior-level position is responsible for maintaining the performance, availability, reliability, and security of multi-user computer systems, virtual environments, and Commercial Off-The-Shelf (COTS) software products.

The successful candidate will bring extensive systems administration experience across Linux and enterprise infrastructure environments, with hands-on expertise in virtualization, patch management, backup and recovery, automation, and vulnerability management. You will work closely with systems administration and Information Assurance teams to sustain secure operations, resolve complex technical issues, and support evolving mission requirements. A Day in the Life -

What You'll Do

• Monitor, maintain, and optimize multi-user computer systems and virtual computing environments to ensure system availability, performance, and reliability.
• Diagnose and resolve complex operating system, application, and infrastructure performance issues.
• Administer Red Hat Linux systems and support infrastructure operating across Microsoft Windows, IBM AIX, and Cisco IOS environments.
• Perform routine system maintenance, operating system patching, software updates, and configuration management to maintain system security and operational readiness.
• Execute backup and recovery operations, ensuring critical files, applications, and system data can be restored when required.
• Support virtualization and container platforms, including OpenStack, VMware, and Red Hat OpenShift.
• Develop and maintain automation solutions using Ansible, Ansible Tower, and scripting to improve system administration efficiency and consistency.
• Manage software licensing and ensure compliance with applicable vendor requirements.
• Collaborate with the Information Assurance (IA) Team to support account management, vulnerability identification, remediation, and system security monitoring.
• Provide system logs, account-monitoring instructions, and technical information to support cybersecurity investigations and incident response.
• Assist with the deployment and integration of software and hardware deliveries, including system configuration and operational testing.
• Provide technical guidance and on-the-job training to operational personnel, contractor teams, and other technical staff.
• Support special projects and work alongside operational crews to troubleshoot and resolve system, network, and infrastructure issues.
• Apply Agile methodologies and collaborate across technical teams to support system improvements and mission objectives. Required Qualifications
• Bachelor's degree in a STEM field.
• 10+ years of relevant professional experience.
• Active DoD Secret clearance with the ability to obtain TS/SCI.
• Demonstrated experience as a Linux Systems Administrator or in a comparable enterprise systems administration role.
• Hands-on experience administering Red Hat Linux environments.
• Experience supporting virtualization and container platforms, including OpenStack or VMware and Red Hat OpenShift.
• Familiarity with Microsoft Windows, IBM AIX, and Cisco IOS environments.
• Experience with system administration, operating system patching, backup and recovery, and software maintenance.
• Knowledge of Ansible, Ansible Tower, and scripting for systems administration and automation.
• Familiarity with Agile methodologies and collaborative project execution.
• Strong troubleshooting, analytical, and problem-solving skills.
• Effective written and verbal communication skills and the ability to work collaboratively within multidisciplinary technical teams.

Preferred Qualifications

• Experience supporting CI/CD pipeline environments and software development infrastructure.
• Familiarity with virtualization, containerization, and software environment development.
• Experience automating infrastructure deployment, configuration management, and system maintenance.
• Additional industry certifications related to Linux, Red Hat, virtualization, or systems administration.
• Experience supporting cybersecurity and Information Assurance teams in secure or classified computing environments.
• Who is Caribou Thunder? Caribou Thunder is a HUBZone-certified small business providing advanced technical and engineering services to the U.S. Department of War and its mission partners. 35+ states and 20+ countries. We've delivered trusted solutions for over two decades - strengthening national readiness across missions on land, undersea, in the air, and throughout LEO, MEO, GEO, and deep space. Why Caribou Thunder? TEAM THUNDER - Mission Focused. Delivery Proven. Ready to Serve. Employee Advocacy Mission Proven Global Reach Skilled Teams Modern Tools Empowering Culture Our engineers and innovators ensure capability from sea floor to space frontier - delivering on time, maintaining compliance, and performing with precision in high-consequence environments. We specialize in Engineering Services, Cybersecurity, Software Development, Modeling & Simulation, Digital Engineering, and Artificial Intelligence - disciplines powering the nation's most complex technical missions. Employee Advocacy + Benefits Our people are the heart of Caribou Thunder. We invest in their growth, flexibility, and well-being - knowing their success drives ours.
• Premium Health, Dental & Vision Insurance
• 401(k) with 6% Company Match
• Flexible PTO & Work Schedule
• Your future, your flexibility, your well-being - we invest in you. Apply and let's connect.
• Education & Certification Reimbursement
• Support for Military Leave
• Work-Life Balance & Traditional Family Values