System Administrator

Cyber Security Jobs; Huntsville (AL); On-site; USD 70,000 - 126,000; Full time

Job summary

Leidos Defense Sensors is seeking a System Administrator to manage Linux, Windows, and cloud platforms, supporting missile defense projects within the BMD simulations portfolio.

The role emphasizes daily administration, security scanning, incident response, and collaboration with agile teams. Requires US citizenship and an active clearance. Onsite in North Alabama, with opportunities across related defense programs.

Qualifications

• Bachelor’s or Master’s degree in a relevant IT field.
• Experience with Linux systems (RHEL) and network services.
• Security+ or equivalent certification within 90 days of start.
• US Citizenship and active security clearance required.

Responsibilities

• Perform daily system administration and O&M in a complex physical/virtual environment.
• Monitor infrastructure and respond to hardware/software incidents; maintain docs.
• Execute IAVA responses and security scans per System Security Plans.
• Collaborate with ISSM and other admins; provide timely updates to users.

Skills

IaC (Ansible)

Azure/AWS

Linux administration

Security+

US Citizenship

Education

Bachelor’s degree

Master’s degree

Tools

Ansible

Azure

AWS

VMware

Nessus

Splunk

WSUS

Job description

Looking for an opportunity to make an impact?

This posting is for multiple opportunities ranging in years of experience. Level of opportunity, including compensation, will be matched to a candidate's experience

At Leidos, we deliver innovative solutions through the efforts of our diverse and talented people who are dedicated to our customers’ success. We empower our teams, contribute to our communities, and operate sustainable. Everything we do is built on a commitment to do the right thing for our customers, our people, and our community. Our Mission, Vision, and Values guide the way we do business.

Your greatest work is ahead!

Leidos’ Defense Sensorsis seeking a System Administrator to join our team...with the ability and experience to work missile defense projects within the BMD Simulations and Analysis Portfolio. As a System Administrator you will manage both unclassified and classified environments across Linux, Windows, and cloud platforms. This role sits at the heart of our Ballistic Missile Defense (BMD) simulation and analysis effort and directly supports agile software-development teams delivering mission-critical capabilities for the nation’s defense. The ideal candidate will possess excellent analytical and problem-solving skills, be a strong team player, and have the ability to establish solid working relationships with peers and technical staff members within the program.

If this sounds like the kind of environment where you can thrive, keep reading!

Leidos Defense Sensors provides a diverse portfolio of systems, solutions, and services covering land, sea, air, space, and cyberspace for customers worldwide. Solutions for Defense include enterprise and mission IT, large-scale intelligence systems, command and control, geospatial and data analytics, cybersecurity, logistics, training, and intelligence analysis and operations support. Our team is solving the world’s toughest security challenges for customers with “can’t fail” missions.

Primary Responsibilities

• The selected individual will be responsible for performing daily system administration and O&M support activities in support of a complex physical and virtual environment. The position entails the daily sustainment of existing computing and network systems. Will be responsible for monitoring infrastructure systems, applications, and processes, and for ensuring that all issues are identified, tracked, and resolved in a timely manner. Individual will provide support for all infrastructure systems and will respond to hardware and software incidents impacting local users as well as working with and taking direction from ISSM.

Additional responsibilities include:

• Working with other system administrators and technicians in identifying, troubleshooting, and correcting hardware and software issues including network connectivity.
• Providing hands on technical assistance in support of overlapping projects and maintaining good inter-departmental relations.
• Communicating with users and publishing status of any system outages, as needed.
• Proactively contacting customers when infrastructure processes are significantly delayed or may impact their ability to complete a business function on time.
• Executing the process for managing information assurance vulnerability alerts (IAVAs) and system security scanning for equipment suites in accordance with the System Security Plans for these systems in order to rapidly and accurately identify and remediate IAVAs.
• Initiating IAVA responses and system security scans; completing remediation; extending IAVA patches and security updates on various IT and network systems.
• Participating in the creation and ongoing maintenance of documentation to ensure clear, concise and accurate information is readily available to assist with incident resolution.
• Providing support for implementing IT enhancements and undertaking project work.
• Handling IT Help Desk calls and emails, ensuring all interactions are handled timely and in a professional manner.
• Utilizing enterprise monitoring solutions to identify alarms that have been triggered against the environments.
• undefined

Basic Qualifications

• Bachelor’s degree with 2-4 years of prior relevant experience or Masters with less than 2 years of prior relevant experience
• Demonstrated experience in one or more of the following: Infrastructure as Code (IaC) using Ansible or similar technology
• Demonstrated experience in one or more of the following: Using Azure/AWS or similar technology
• Demonstrated experience in one or more of the following: Linux Servers, DNS servers, Domain controllers, network storage devices and HP or Dell servers
• 3+ Years’ experience with Linux Operating System Administration (i.e., RHEL8, etc.)
• Demonstrated experience designing, configuring and installing information systems such as routers, servers, switches, storage systems and laptops.
• Security+ Certification or obtain within 90-days of start.
• U.S. Citizenship required
• Active secret clearance
• Full time onsite support
• Candidate must be a resident of the North Alabama area

Preferred Qualifications

• Demonstrated experience deploying the complete DevSecOps lifecycle including integration of build pipelines, automated deployments, and compliance scanning using test driven development.
• Experience with vulnerability remediation and security management (system hardening, log management, configuration management (i.e., Nessus, McAfee, WSUS, Splunk, ACAS, SCAP, HBSS, etc.))
• Experience with Virtualization (i.e., VMware, Horizon, vSphere, vCenter, vSAN)
• Experience with Risk Management Framework (RMF) Requirements and Security Technical Implementation Guide (STIG) Implementation
• Demonstrated experience in the deployment, automated deployments, and compliance scanning using test driven development.
• Demonstrated experience with issue tracking tools such as Gitlab/VersionOne/Agility.
• Relevant DoD and/or Industry work experience in Missile Defense

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:

October 26, 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:

Pay Range $69,550.00 - $125,725.00

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.

About 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 $16.7 billion for the fiscal year ended January 3, 2025. For more information, visit www.Leidos.com.

Pay and Benefits

Pay and benefits are fundamental to any career decision. That's why we craft compensation packages that reflect the importance of the work we do for our customers. Employment benefits include competitive compensation, Health and Wellness programs, Income Protection, Paid Leave and retirement. More details are available at www.leidos.com/careers/pay-benefits.

Securing Your Data

Beware of fake employment opportunities using Leidos’ name. Leidos will never ask you to provide payment-related information during any part of the employment application process (i.e., ask you for money), nor will Leidos ever advance money as part of the hiring process (i.e., send you a check or money order before doing any work). Further, Leidos will only communicate with you through emails that are generated by the Leidos.com automated system - never from free commercial services (e.g., Gmail, Yahoo, Hotmail) or via WhatsApp, Telegram, etc. If you received an email purporting to be from Leidos that asks for payment-related information or any other personal information (e.g., about you or your previous employer), and you are concerned about its legitimacy, please make us aware immediately by emailing us at [e-mail].

If you believe you are the victim of a scam, contact your local law enforcement and report the incident to the U.S. Federal Trade Commission.

Commitment to Non-Discrimination

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.