Senior Linux Systems Administrator

Job Description

Type of Requisition: Regular

Clearance Level Must Currently Possess: Top Secret/SCI

Clearance Level Must Be Able To Obtain: Top Secret/SCI

Public Trust/Other

Required:

None

Job Family: IT Infrastructure and Operations

Skills: Linux, Red Hat, System Administration

Certifications: None

Experience: 3+ years of related experience

US Citizenship

Required:

Yes

Advance how our customers operate while you advance your career. Join GDIT as a Senior Linux Systems Administrator and build an impactful career in enterprise IT, collaborating with people who are driven and resourceful like you.

Meaningful Work and Personal Impact

As a Senior Linux Systems Administrator
, the work you’ll do at GDIT will be impactful to the mission of USCENTCOM. You will play a crucial role in configuration, maintenance, and optimization of Linux‑based server environments supporting a large‑scale enterprise infrastructure. This role supports mission‑critical systems across an environment of more than 5,000 users, 1,000 servers, and 10,000 endpoints. The administrator will collaborate closely with other Enterprise Services teams to ensure system availability, performance, security compliance, and operational efficiency in support of USCENTCOM mission requirements.

• Configure, deploy, and maintain Linux server environments, including physical and virtual systems.
• Administer Red Hat and CentOS Linux systems, ensuring stability, performance, and security compliance.
• Configure and manage Linux services such as Apache, Nginx, DNS, DHCP, LDAP, and related system services.
• Monitor system performance and availability, proactively identifying and resolving issues before they impact operations.
• Troubleshoot and resolve complex system issues, including problems without existing documented solutions.
• Implement system patches, updates, and security hardening in accordance with DoD and organizational policies.
• Manage SSL/TLS certificate lifecycle activities supporting Linux‑based services.
• Collaborate with infrastructure, network, storage, and security teams to design and implement Linux‑based solutions aligned with enterprise requirements.
• Participate in system upgrades, migrations, and the deployment of new Linux infrastructure components.
• Ensure incidents, problems, and service requests are tracked, prioritized, escalated, and resolved appropriately.
• Develop and maintain technical documentation, including system configurations, troubleshooting guides, and standard operating procedures.
• Produce reports and data sets to inform leadership of system performance, trends, and improvement opportunities.
• Provide technical mentorship and guidance to junior administrators and team members.
• Support projects focused on improving the security, efficiency, scalability, and resilience of Linux environments.
• Assist in developing and enforcing system policies and best practices.
• Participate in enterprise initiatives to modernize and standardize infrastructure services.
• Contribute to continuous improvement efforts across Enterprise Services teams.

• Certification:
  Applicable DoD 8140 or DoD 8570 Certification
• Experience:
  
  3+ years of related experience
• Required skills:
  • Demonstrated proficiency administering Red Hat and CentOS Linux systems in enterprise environments.
  • Strong experience building, deploying, and maintaining Linux server infrastructures.
  • Expertise in system performance tuning, availability management, and security hardening.
  • Experience implementing patches, updates, and configuration changes in controlled environments.
  • Ability to troubleshoot and resolve complex systems issues under operational constraints.
  • Strong documentation skills for system configurations, procedures, and troubleshooting guides.
  • Proven ability to work collaboratively across multiple IT disciplines.
• Desired
  
  Skills:
  • Red Hat Certified System Administrator (RHCSA) or higher
  • ITIL 4 Foundation Certification
  • Experience supporting USCENTCOM environments and familiarity with mission systems and operational requirements.
  • Knowledge of enterprise‑scale infrastructure operations.
  • Experience mentoring junior administrators and contributing to team development.
• Securi…