Senior Windows System Administrator; requires TS/SCI Polygraph up front.
Leidos has a new and exciting opportunity for a Senior Windows 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!
Job Summary
Leidos is seeking a Senior Windows System Administrator to join a high-performing Agile team operating within the Scaled Agile Framework (SAFe) in support of a complex, fast-paced program. In this role, the selected candidate will provide daily systems administration and operations and maintenance support across multiple systems with a broad geographic footprint. Key responsibilities include responding to system engineering requests that support operational requirements, as well as engineering, deploying, and sustaining new capabilities within the environment.
Primary Responsibilities
The selected candidate will be responsible for monitoring test infrastructure systems, applications, and processes to ensure issues are identified, tracked, and resolved in a timely manner. This role also includes supporting server, router, and firewall configuration, as well as performing security management and application performance optimization activities in an environment made up of VMware server hosts, Windows and Linux guest servers, and Virtual Desktop Infrastructure (VDI). Additional responsibilities include:
• Maintaining multiple virtual server clusters and addressing system scan findings, vulnerability management patching, and Active Directory configuration issues.
• Using enterprise monitoring tools to detect, assess, and respond to alerts.
• Providing technical support to partner workgroups on overlapping efforts while maintaining strong interdepartmental collaboration.
• Managing Information Assurance Vulnerability Alerts (IAVAs) and system security scanning in accordance with applicable System Security Plans, ensuring vulnerabilities are identified and remediated quickly and accurately.
• Initiating IAVA responses and system security scans, completing remediation actions, deploying patches and security updates to designated sites, and executing monthly security scans.
• Identifying and resolving hardware and software problems.
• Proactively notifying customers when test infrastructure delays may affect their ability to complete business functions on time and communicating system outages and publishing status updates to users, as needed.
• Authoring and maintaining clear, accurate, and concise documentation.
• Responding to calls and emails in a timely and professional manner.
• Planning and implementing IT enhancements and supporting project-related work.
• Responding to system administration, operations, and maintenance issues on an on-call basis when required.
Basic Qualifications
• Bachelor’s degree in Computer Science, Information Technology, or a related technical field and 12 years of prior relevant experience. Additional experience may be substituted for a degree.
• Must have at least 7 years of Windows administration experience.
• Must have at least 7 years of experience in information security management, with demonstrated expertise in security governance, risk management, compliance, and operational security functions.
• Must have at least 5 years of experience with each of the following:
o Implementing and managing Windows Active Directory and DNS environments
o Creating and managing Group Policy Objects (GPOs)
o Microsoft SCCM
o Microsoft Exchange administration and Exchange Management Shell
• Must have experience with Windows Command Line, PowerShell, and PowerShell scripting.
• Strong understanding of advanced security protocols, standards, and information security principles is a must.
• Experience with software and security architectures.
• Hands-on experience with IAVA management.
• Hands-on experience supporting users, optimizing system operations, and monitoring enterprise IT systems.
• Commitment to best practices, including compliance with maintenance windows and change control procedures.
• Familiarity with Windows and Linux operating systems, VMware, and networking technologies including switches, routers, LANs, and cabling.
• Must have strong analytical skills, attention to detail, and the ability to work effectively both independently and as part of a team.
• Clearance Required: Must have TS/SCI with Polygraph.
Preferred Qualifications
• Experience documenting and supporting security accreditation and certification activities.
• Experience with network security technologies, including multi-domain solutions, PKI, SSPs, and vulnerability assessments.
• Experience with data center design and configuration, including rack-and-stack, power planning, and equipment placement.
• Experience with VMware.
• Experience using automation tools such as Ansible or SaltStack.
• Experience serving in a System Administrator role supporting software configuration management and development environments.
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 – apply today.
careers.leidos.com/CONMD
CSSKEY
CONMD
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.
Original Posting:August 28, 2026For 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.
The Leidos pay range for this job level is a general guideline only and 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.
Skills Required
- Bachelor's degree in Computer Science, Information Technology, or a related technical field, plus 12 years of relevant experience; additional experience may substitute for the degree
- At least 7 years of Windows administration experience
- At least 7 years of information security management experience, including security governance, risk management, compliance, and operational security
- At least 5 years implementing and managing Windows Active Directory and DNS environments
- At least 5 years creating and managing Group Policy Objects
- At least 5 years of Microsoft SCCM experience
- At least 5 years of Microsoft Exchange administration and Exchange Management Shell experience
- Experience with Windows Command Line, PowerShell, and PowerShell scripting
- Strong understanding of advanced security protocols, standards, and information security principles
- Experience with software and security architectures
- Hands-on experience with IAVA management
- Hands-on experience supporting users, optimizing system operations, and monitoring enterprise IT systems
- Commitment to maintenance windows, change control procedures, and other best practices
- Familiarity with Windows and Linux operating systems, VMware, switches, routers, LANs, and cabling
- Strong analytical skills, attention to detail, and ability to work independently and collaboratively
- Experience documenting and supporting security accreditation and certification activities
- Experience with multi-domain solutions, PKI, SSPs, network security technologies, and vulnerability assessments
- Experience with data center design and configuration, including rack-and-stack, power planning, and equipment placement
- Experience with VMware
- Experience using Ansible or SaltStack
- Experience supporting software configuration management and development environments as a System Administrator
- TS/SCI clearance with Polygraph required upfront
Leidos Compensation & Benefits Highlights
The following summarizes recurring compensation and benefits themes identified from responses generated by popular LLMs to common candidate questions about Leidos and has not been reviewed or approved by Leidos.
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Healthcare Strength — Healthcare coverage is described as comprehensive, with multiple plan options, low office-visit copays in some plans, and access to mental health and wellness support tools. The availability of HSA/FSA options and employer contributions is positioned as a meaningful part of the total package.
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Retirement Support — Retirement benefits are framed as a strong component of total rewards, highlighted by a 401(k) match and immediate vesting in the standard package. The Employee Stock Purchase Plan is also presented as an additional long-term wealth-building feature.
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Wellbeing & Lifestyle Benefits — Wellbeing and lifestyle supports extend beyond core insurance, including wellness programs, fitness-related stipends, and assistance resources. Work flexibility and related perks are also included as part of the broader rewards experience.
Leidos Insights
What We Do
We Are Leidos For 50 years we have been tackling some of the biggest problems that face our nation and our world. OUR MISSION Through our culture of innovation and history of performance, we develop deep customer trust built on integrity and create enduring solutions that improve our world. Leidos is a science and technology solutions leader working to address some of the world’s toughest challenges in the defense, intelligence, homeland security, civil, and healthcare markets. The company’s 43,000 employees support vital missions for government and commercial customers. Headquartered in Reston, Va., Leidos reported annual revenues of approximately $11.09 billion for the fiscal year ended January 3, 2020. Leidos was cited for the meaningful work employees perform that is challenging, impactful, and aligned with our customers’ missions as reasons professionals want to work and stay at our company. Leidos has also been named to lists including Forbes’ Best Employers for Diversity, Forbes’ America’s Best Employers for Women, Military Times Best for Vets Employers, and Ethisphere Institute’s World's Most Ethical Companies®. Employees enjoy career enrichment opportunities available through mobility and development and experience rewarding relationships with supportive supervisors and talented colleagues and customers. Employees appreciate our flexible work environment, allowing for and encouraging a true work-life balance. Our professionals are also excited about our Employee Resource Groups, like the newly launched Collaborative Outreach with Remote and Embedded Employees (CORE), which strives to create an environment where every employee, regardless of location, feels fully engaged as a valued employee of Leidos. Your most important work is ahead.








