Mid/Senior System Administrator

Leidos LLC; Maryland; On-site; USD 100,000 - 140,000; Full time

Benefits offered by this job

Paid Time Off

11 holidays (paid)

401K with 6% company match

Flexible schedules

Discounted stock purchase

Technical upskilling

Education and training support

Parental paid leave

Job summary

Leidos LLC is seeking a Mid/Sr System Administrator to support a large, complex network environment across distributed systems. The role involves delivering solutions that meet operations needs, upgrading, sustaining, and maintaining capabilities in a fast-paced setting with air-gapped domains.

The position requires strong system administration and troubleshooting skills, with responsibilities spanning installation, configuration, security management, and cross-team collaboration.

Qualifications

• Bachelor's degree in a technical field with 8+ years of relevant experience.
• 5+ years of hands-on experience supporting Linux and Windows servers/workstations.
• 5+ years of OS and application hardening, including DISA and high‑assurance environments.
• 5+ years of software/hardware deployment, patching, OS, and backup/restore.
• Proficient with Windows Server 2016/2019 and Active Directory.
• Ability to travel domestically and internationally (CONUS/OCONUS).
• Clearance: TS/SCI with Polygraph.

Responsibilities

• Install applications, administer systems and processes, and resolve issues promptly.
• Optimize server and desktop configurations for reliable operations.
• Perform security management and performance optimization tasks.
• Manage web-based information storage/sharing applications and complex server enclaves.
• Maintain documentation for incident resolution and system configurations.
• Communicate outages and upgrades with users and management.

Skills

System administration

Linux

Windows Server

Active Directory

Security hardening

Education

Bachelor's degree in a technical field

Tools

Trellix ePO

SALT

Python

Red Hat 7/8

VMware

Apache Tomcat

IIS

SQL Server

PowerShell

KVMs

Job description

Mid/Sr System Administrator

This role comes with a 15k sign on bonus.

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:

• 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

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.

Primary Responsibilities

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.

Basic Qualifications

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.

• 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.

Preferred Qualifications

Experience building, configuring, and maintaining large, distributed Trellix ePO environments from the ground up. Strong scripting experience with SALT and Python. Hands‑on experience with Red Hat 7/8, VMware, Apache Tomcat, IIS, SQL Server, and KVMs. Experience supporting security accreditation and certification, advanced security protocols, and network security technologies, including PKI, SSP, multi‑domain environments, and vulnerability assessment. Experience with client and server virtualization, hardware installation and troubleshooting, system optimization, and related tools such as disk arrays, PowerShell, PowerCLI, HSMs, and NTP. Solid understanding of information security principles, software security, and security architecture.

• Experience building, configuring, and maintaining large, distributed Trellix ePO environments from the ground up.
• Strong scripting experience with SALT and Python.
• Hands‑on experience with Red Hat 7/8, VMware, Apache Tomcat, IIS, SQL Server, and KVMs.
• Experience supporting security accreditation and certification, advanced security protocols, and network security technologies, including PKI, SSP, multi‑domain environments, and vulnerability assessment.
• Experience with client and server virtualization, hardware installation and troubleshooting, system optimization, and related tools such as disk arrays, PowerShell, PowerCLI, HSMs, and NTP.
• Solid understanding of information security principles, software security, and security architecture.

Pay Range: Pay Range $92,300.00 - $166,850.00

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 and Benefits

Pay and benefits are fundamental to any career decision.

• competitive compensation
• Health and Wellness programs
• Income Protection
• Paid Leave and Retirement

Employment benefits include competitive compensation, Health and Wellness programs, Income Protection, Paid Leave and Retirement.

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.

Original Posting: August 28, 2026

Leidos Leidos is an industry and technology leader serving government and commercial customers with smarter, more efficient digital and mission innovations. Headquartered in Reston, Virginia, with 47,000 global employees, Leidos reported annual revenues of approximately $17.2 billion for the fiscal year ended January 2, 2026. For more information, visit www.Leidos.com.

Securing Your Data

Leidos will never ask you to provide payment-related information at any part of the employment application process. And Leidos will communicate with you only through emails that are sent from a Leidos.com email address. If you receive an email purporting to be from Leidos that asks for payment-related information or any other personal information, please report the email to [e-mail].

Commitment and Diversity

All qualified applicants will receive consideration for employment without regard to sex, race, ethnicity, age, national origin, citizenship, religion, physical or mental disability, medical condition, genetic information, pregnancy, family structure, marital status, ancestry, domestic partner status, sexual orientation, gender identity or expression, veteran or military status, or any other basis prohibited by law. Leidos will also consider for employment qualified applicants with criminal histories consistent with relevant laws.