Leidos Corporate Information Security Office (CISO), reporting through the Digital sector, is seeking a Linux and Windows System Administrator to support and maintain complex classified environments. The selected candidate will be responsible for administering, securing, troubleshooting, and maintaining Windows and Linux systems across physical and virtual infrastructures. This role supports mission-critical operations by ensuring system availability, compliance with security requirements, and reliable day-to-day operations within a secure enterprise environment.
Location: All work will be performed onsite in our Beavercreek, OH office.
Clearance: You must currently carry an active DoD Secret clearance to qualify for consideration.
Primary Responsibilities
Administer and maintain Windows Workstations, Windows Server, and Linux systems (RHEL, Rocky Linux, Ubuntu) across physical, virtual, and air-gapped environments.
Perform Tier 2 incident resolution, troubleshoot technical issues, conduct root-cause analysis, and collaborate with engineering, cybersecurity, and stakeholders to resolve complex problems.
Execute system patching, vulnerability remediation, configuration management, and compliance activities.
Implement and maintain monitoring, logging, backup and recovery solutions, and operational documentation/runbooks.
Support account and access administration in accordance with least-privilege principles and organizational security policies.
Automate repetitive administrative tasks using PowerShell, Bash, Ansible, or similar automation tools.
Deploy and maintain operating system images using PXE/network boot, Kickstart, disk imaging, answer files, and automated installation methods.
Perform system hardening and security compliance using DISA STIGs, SCAP, and NIST 800-53 security controls.
Administer and troubleshoot Active Directory, DNS, DHCP, file servers, virtualization platforms, and Layer 2 network switching, including VLAN configuration, TCP/IP connectivity, and switch port administration in an air-gapped environment.
Support dual-boot bare-metal systems and virtualized environments.
Participate in after-hours support and on-call rotations as required.
Research, analyze, and resolve Windows, Linux, and networking issues to maintain system availability, reliability, and performance.
Basic Qualifications
Current Active DoD Secret security clearance.
Current CompTIA Security+ certification.
Bachelor's degree in a technical field with 2–4 years of relevant experience. Additional years of experience may be considered in lieu of a degree.
Experience administering Windows Server and Linux systems in secure or air-gapped environments.
Experience implementing DISA STIGs, SCAP, NIST 800-53 security controls, and system hardening practices.
Experience administering:
Active Directory
DNS
DHCP
File Servers
Experience building, integrating, maintaining, troubleshooting, and remediating Windows and Linux systems.
Experience deploying operating systems using PXE, Kickstart, ISO/disk imaging, and automated installation methods.
Experience configuring and troubleshooting Layer 2 switching, VLANs, TCP/IP, and network connectivity.
Experience managing Windows and Linux updates, patching, and vulnerability remediation.
Ability to develop automation scripts using PowerShell and Bash.
Familiarity with Linux software repository management.
Ability to work independently and collaboratively with minimal supervision.
Strong analytical, communication, and problem-solving skills.
Preferred Qualifications
Red Hat Certified System Administrator (RHCSA) certification.
Experience administering VMware, Hyper-V, or other virtualized environments.
Experience with automation and configuration management tools, including Ansible.
Experience supporting secure or classified DoD environments.
Knowledge of backup, recovery, logging, and monitoring solutions.
Experience performing DISA STIG remediation, SCAP compliance validation, and vulnerability scanning using Tenable Nessus.
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:July 2, 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
- Current active DoD Secret security clearance
- CompTIA Security+ certification
- Bachelor's degree in a technical field or equivalent experience (2-4 years relevant experience)
- Experience administering Windows Server and Linux systems (RHEL, Rocky, Ubuntu) in secure or air-gapped environments
- Experience implementing DISA STIGs, SCAP, and NIST 800-53 security controls and system hardening
- Experience administering Active Directory, DNS, DHCP, and file servers
- Experience deploying operating systems using PXE, Kickstart, ISO/disk imaging, and automated installation methods
- Experience configuring and troubleshooting Layer 2 switching, VLANs, TCP/IP, and network connectivity
- Experience managing updates, patching, and vulnerability remediation
- Ability to develop automation scripts using PowerShell and Bash
- Familiarity with Linux software repository management
- Strong analytical, communication, and problem-solving skills; ability to work independently and collaboratively
- Red Hat Certified System Administrator (RHCSA)
- Experience administering VMware, Hyper-V, or other virtualization platforms
- Experience with Ansible and other automation/configuration management tools
- Experience performing DISA STIG remediation, SCAP validation, and vulnerability scanning with Tenable Nessus
- Experience supporting secure or classified DoD environments
- Knowledge of backup, recovery, logging, and monitoring solutions
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.
