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Leidos is seeking a Mid/Sr System Administrator to support a large, complex network environment across air-gapped domains. You will install applications, harden systems, and manage security, patching, and backup tasks while coordinating with end users and tiers of support.
The role requires strong Linux/Windows administration, experience with AD, and the ability to travel for CONUS/OCONUS assignments. TS/SCI with polygraph clearance is required.
Leidos has a new and exciting opportunity for a Mid/Sr System Administrator in our Intel Sector's Cyber & Analytics Business Area (CABA). Our talented team is at the forefront in Security Engineering, Computer Network Operations (CNO), Mission Software, Analytical Methods and Modeling, Signals Intelligence (SIGINT), and Cryptographic Key Management. At Leidos , we offer competitive benefits , including Paid Time Off, 11 paid Holidays, 401K with a 6% company match and immediate vesting, Flexible Schedules, Discounted Stock Purchase Plans, Technical Upskilling, Education and Training Support, Parental Paid Leave, and much more. Join us and make a difference in National Security!
The selected individual will provide system administration support for a large, complex network environment with geographically distributed systems. The role supports system engineering requests by delivering solutions that meet operational needs, and by upgrading, sustaining, and maintaining existing capabilities. The candidate must be comfortable working in a fast-paced environment that includes multiple air-gapped systems, each with its own domain and supporting infrastructure. The position also requires maintaining a complex IT environment involving multiple users, as well as associated storage and network infrastructure. This role requires an energetic, focused, and driven individual who can adapt quickly to changing priorities. The candidate must demonstrate strong system administration and troubleshooting skills and work effectively with the team to execute a variety of network-centric system administration tasks.
The selected candidate will be responsible for installing applications, administering systems and processes, and ensuring issues are identified and resolved in a timely manner. This role also includes optimizing server and desktop configurations to support reliable, continuous, and efficient operations, as well as performing security management and application performance optimization activities.
Additional responsibilities may include:
Administration/sustainment of a system that provides a web-based application for storing, sharing, and distributing information.
Creating and maintaining complex server enclaves, including analyzing system scanning reports, patching, cert renewals, vulnerability management assessments, and active directory configurations.
Identifying and correcting hardware and software issues.
Responding to system administration, operations, and maintenance problems, and developing re-work solutions.
Creating and maintaining documentation of complex server/network environments to ensure that clear, concise and accurate information is readily available for incident resolution.
Communicating with users and external support personnel regarding system outages and upgrades and conferring with upper management regarding recommended resolution options.
Bachelor’s Degree in System Engineering, Computer Science, Information Systems, Engineering Science, Engineering Management, or a related technical field and at least 8 years of relevant experience. Additional experience may be substituted for a degree.
Must have substantial experience working as a systems administrator providing direct support to large groups of end users and technical staff (developers, testers, engineers, etc.).
Must have at least 5 years of hands-on experience supporting Linux and Microsoft-based servers and workstations.
Must have at least 5 years of hands-on experience with operating system and application hardening, including DISA, best practices, and high-assurance environments.
Must have at least 5 years of hands-on experience with software and hardware deployment, patch management, operating systems, and system backup and restore functions.
Must be proficient with Windows Server 2016, 2019, and Active Directory.
Ability to travel is required, including local area travel and occasional 1-2 week CONUS and OCONUS trips on an annual basis.
Clearance Required: Must have TS/SCI with Polygraph.
At Leidos , the opportunities are boundless. We challenge our staff with interesting assignments that allow them to thrive professionally and personally. For us, helping you grow your career is good business. We look forward to learning more about you.
If you’re looking for comfort, keep scrolling. At Leidos, we outthink, outbuild, and outpace the status quo - because the mission demands it. We're not hiring followers. We're recruiting the ones who disrupt, provoke, and refuse to fail. Step 10 is ancient history. We're already at step 30 - and moving faster than anyone else dares.
August 28, 2026
For U.S. Positions: While subject to change based on business needs, Leidos reasonably anticipates that this job requisition will remain open for at least 3 days with an anticipated close date of no earlier than 3 days after the original posting date as listed above.
Pay Range $92,300.00 - $166,850.00
The Leidos pay range for this job level is a general guideline onlyand not a guarantee of compensation or salary. Additional factors considered in extending an offer include (but are not limited to) responsibilities of the job, education, experience, knowledge, skills, and abilities, as well as internal equity, alignment with market data, applicable bargaining agreement (if any), or other law.