1,178 System Administrator jobs in the United States

Mantech seeks a motivated, career and customer-oriented Linux System Administrator to join our team in Laurel, MD. 

You will be part of a dedicated team delivering enterprise infrastructure capabilities for a global workforce that supports a wide range of national defense missions. This role directly supports the Enterprise Infrastructure Services (EIS) organization—the foundation of all Enterprise Information Technology (EIT) for MPO.
  

Responsibilities include but are not limited to:

• Configure and manage Linux operating systems. Installs/loads operating system software, troubleshoots maintains integrity and configures network components along with implementing operating systems enhancements to improve reliability and performance.
• Provides support for implementation, troubleshooting and maintenance of Information Technology (IT) systems.
• Manage IT system infrastructure and any processes related to these systems.
• Provide support to IT systems including day-to-day operations, monitoring and problem resolution for all the client/server/storage/network devices, mobile devices, etc.
• Provide support for the dispatch system and hardware problems and will remain involved in the resolution process.
• Optimize system operations and resource utilization and perform system capacity analysis and planning.
• Analyze and resolve complex problems associated with server hardware, applications and software integration.

Minimum Qualifications:

• Bachelor’s degree in a technical discipline from an accredited college or university with 12+ years of experience as a System Engineer supporting programs and contracts of similar scope, type, and complexity. 3 years of additional experience with an associate’s degree might be substituted OR 8 years of additional experience and a high school diploma
• Must be proficient with troubleshooting in a Linux Red Hat environment.
• Experience with VMWare
• Demonstrated experience with modern automation/configuration tools such as Splunk or Ansible
• IAT II certification (DoD 8140 required within 60 days of starting employment.  Acceptable certifications include CCNA-Security/CySA+/GICSP/GSEC/Security+ CE/CND/ or SSCP)

Preferred Qualifications:

• Experience/familiarization with full lifecycle management of Linux systems, to include provisioning, configuration management and patching.
• Red Hat Certified System Administration Certification.
• Experience with NetAPP

Clearance Requirements:

• Must have a current/active Top Secret/SCI with Polygraph

Physical Requirements:

• The person in this position must be able to remain in a stationary position 50% of the time.
• Occasionally move about inside the office to collaborate with other leaders/teams, use standard office automation equipment, and virtual communication.

ManTech seeks an experienced and passionate, career and customer-oriented System Administrator to join our team located in the Fort Meade, MD area.

Responsibilities include, but are not limited to:

• Design, engineer, and implement automated hardening scripts for internal servers adding scalability while circumventing manual process for new operating system rollout.
• Configure host-based intrusion detection systems.
• Monitor and troubleshoot/examine detected anomalies.
• Developed automation script adding new servers to IPA replacing human error and manual process
• Analyze system and security logs while responding to discovered real time events providing SOC status updates.
• Engineer ansible script automating creation of user accounts in IPA replacing manual process
• Review audits confirming hardening script successfully executed while checking for other vulnerabilities and/or configuration errors.
• Host design and review meetings providing security insight, team updates, goals, projections to branch management.

Minimum Qualifications:

• Bachelor’s degree in computer science or a related discipline and 10 years related experience or an Associate’s degree in computer science or a related discipline and 15 years related experience.
• 10+ years’ experience in systems administration of hardware and software in support of developing and testing of information technology systems .
• Heavy Linux administration experience.
• Experience using Ansible or comparable tools.
• Experience with cross-domain solutions or NiFi.
• Experience with integrated processing environments such as a Storage Area Network  .

Preferred Qualifications:

• Experience with DevOps tools such as Docker, Kubernetes, SALT, Puppet desirable .
• Experience with cross-domain solutions or NiFi is desirable.
• Experience writing scripting languages (Bash, Shell, Python, Perl). 
• Demonstrated experience working with a team to introduce and integrate new technologies into existing production environments. 
• Proficiency in working with applicable network devices to include routers and switches, gateways and hubs. 
• Experience with computer networking protocols including, but not limited to TCP, IP, UDP, HTTP, DHCP, and DNS.

Clearance Requirement:

• Must have a current/active TS/SCI with Poly

Physical Requirements:

• Must be able to remain in a stationary position at least 50% of the time.
• Needs to occasionally move about inside the office to access file cabinets, office machinery, etc.
• Constantly operate a computer and other office productivity machinery, such as, the copy machine/fax machine/computer/printer.

ManTech seeks an experienced and passionate, career and customer-oriented Linux System Administrator to join our team located in the Fort Meade, MD area.

Responsibilities include, but are not limited to:

• Design, engineer, and implement automated hardening scripts for internal servers adding scalability while circumventing manual process for new operating system rollout.
• Configure host-based intrusion detection systems.
• Monitor and troubleshoot/examine detected anomalies.
• Developed automation script adding new servers to IPA replacing human error and manual process
• Analyze system and security logs while responding to discovered real time events providing SOC status updates.
• Engineer ansible script automating creation of user accounts in IPA replacing manual process
• Review audits confirming hardening script successfully executed while checking for other vulnerabilities and/or configuration errors.
• Host design and review meetings providing security insight, team updates, goals, projections to branch management.

Minimum Qualifications:

• 7 year’s experience in systems administration of hardware and software in support of developing and testing of information technology systems 
• Experience with Linux administration
• Experience using Ansible or comparable tools
• Experience working with a team to introduce and integrate new technologies into existing production environments 
• Experience with integrated processing environments such as a Storage Area Network  

Preferred Qualifications:

• Experience with DevOps tools such as Docker, Kubernetes, SALT, Puppet desirable 
• Experience with cross-domain solutions or NiFi desirable for some positions 
• Experience writing scripting languages (Bash, Shell, Python, Perl) 
• Proficiency in working with applicable network devices to include routers and switches, gateways and hubs 
• Experience with computer networking protocols including, but not limited to TCP, IP, UDP, HTTP, DHCP, and DNS   
• Ability to handle stress and work under pressure
• Competence in computer operating systems

Clearance Requirement:

• Must have a current/active TS/SCI with Poly

Physical Requirements:

• Must be able to remain in a stationary position at least 50% of the time.
• Needs to occasionally move about inside the office to access file cabinets, office machinery, etc.
• Constantly operate a computer and other office productivity machinery, such as, the copy machine/fax machine/computer/printer.

ManTech seeks an experienced and passionate, career and customer-oriented System Administrator to join our team located in the Fort Meade, MD area.

Responsibilities include, but are not limited to:

• Design, engineer, and implement automated hardening scripts for internal servers adding scalability while circumventing manual process for new operating system rollout.
• Configure host-based intrusion detection systems.
• Monitor and troubleshoot/examine detected anomalies.
• Developed automation script adding new servers to IPA replacing human error and manual process
• Analyze system and security logs while responding to discovered real time events providing SOC status updates.
• Engineer ansible script automating creation of user accounts in IPA replacing manual process
• Review audits confirming hardening script successfully executed while checking for other vulnerabilities and/or configuration errors.
• Host design and review meetings providing security insight, team updates, goals, projections to branch management.

Minimum Qualifications:

• Bachelor’s degree in computer science or a related discipline
• 10+ years’ of experience in systems administration of hardware and software in support of developing and testing of information technology systems; an Associates degree and 5 additional years’ experience might be substituted for a degree.
• Heavy Windows and Linux administration experience
• Highly proficient with Active Directory
• Experience with virtualization
• Experience with PowerShell scripting
• Experience with Keycloak
• Experience using Ansible or comparable tools
• Experience with cross-domain solutions or NiFi
• Experience with integrated processing environments such as a Storage Area Network  

Preferred Qualifications:

• Experience with DevOps tools such as Docker, Kubernetes, SALT, Puppet desirable 
• Experience writing scripting languages (Bash, Shell, Python, Perl) 
• Experience with  working with a team to introduce and integrate new technologies into existing production environments 
• Experience in working with applicable network devices to include routers and switches, gateways and hubs 
• Experience with computer networking protocols including, but not limited to TCP, IP, UDP, HTTP, DHCP, and DNS   

Clearance Requirement:

• Must have a current/active TS/SCI with Poly

Physical Requirements:

• Must be able to remain in a stationary position at least 50% of the time.
• Needs to occasionally move about inside the office to access file cabinets, office machinery, etc.
• Constantly operate a computer and other office productivity machinery, such as, the copy machine/fax machine/computer/printer.

Mantech seeks a motivated, career and customer-oriented Linux System Administrator to join our team in Laurel, MD. 

You will be part of a dedicated team delivering enterprise infrastructure capabilities for a global workforce that supports a wide range of national defense missions. This role directly supports the Enterprise Infrastructure Services (EIS) organization—the foundation of all Enterprise Information Technology (EIT) for MPO.
  

Responsibilities include but are not limited to:

• Configure and manage Linux operating systems. Installs/loads operating system software, troubleshoots maintains integrity and configures network components along with implementing operating systems enhancements to improve reliability and performance.
• Provides support for implementation, troubleshooting and maintenance of Information Technology (IT) systems.
• Manage IT system infrastructure and any processes related to these systems.
• Provide support to IT systems including day-to-day operations, monitoring and problem resolution for all the client/server/storage/network devices, mobile devices, etc.
• Provide support for the dispatch system and hardware problems and will remain involved in the resolution process.
• Optimize system operations and resource utilization and perform system capacity analysis and planning.
• Analyze and resolve complex problems associated with server hardware, applications and software integration.

Minimum Qualifications:

• Bachelor’s degree in a technical discipline from an accredited college or university with 12+ years of experience as a System Engineer supporting programs and contracts of similar scope, type, and complexity. 3 years of additional experience with an associate’s degree might be substituted OR 8 years of additional experience and a high school diploma
• Must be proficient with troubleshooting in a Linux Red Hat environment.
• Experience with VMWare
• Demonstrated experience with modern automation/configuration tools such as Splunk or Ansible
• IAT II certification (DoD 8140 required within 60 days of starting employment.  Acceptable certifications include CCNA-Security/CySA+/GICSP/GSEC/Security+ CE/CND/ or SSCP)

Preferred Qualifications:

• Experience/familiarization with full lifecycle management of Linux systems, to include provisioning, configuration management and patching.
• Red Hat Certified System Administration Certification.
• Experience with NetAPP

Clearance Requirements:

• Must have a current/active Top Secret/SCI with Polygraph

Physical Requirements:

• The person in this position must be able to remain in a stationary position 50% of the time.
• Occasionally move about inside the office to collaborate with other leaders/teams, use standard office automation equipment, and virtual communication.

ManTech seeks an experienced and passionate, career and customer-oriented System Administrator to join our team located in the Fort Meade, MD area.

Responsibilities include, but are not limited to:

• Design, engineer, and implement automated hardening scripts for internal servers adding scalability while circumventing manual process for new operating system rollout.
• Configure host-based intrusion detection systems.
• Monitor and troubleshoot/examine detected anomalies.
• Developed automation script adding new servers to IPA replacing human error and manual process
• Analyze system and security logs while responding to discovered real time events providing SOC status updates.
• Engineer ansible script automating creation of user accounts in IPA replacing manual process
• Review audits confirming hardening script successfully executed while checking for other vulnerabilities and/or configuration errors.
• Host design and review meetings providing security insight, team updates, goals, projections to branch management.

Minimum Qualifications:

• Bachelor’s degree in computer science or a related discipline and 10 years related experience or an Associate’s degree in computer science or a related discipline and 15 years related experience.
• 10+ years’ experience in systems administration of hardware and software in support of developing and testing of information technology systems .
• Heavy Linux administration experience.
• Experience using Ansible or comparable tools.
• Experience with cross-domain solutions or NiFi.
• Experience with integrated processing environments such as a Storage Area Network  .

Preferred Qualifications:

• Experience with DevOps tools such as Docker, Kubernetes, SALT, Puppet desirable .
• Experience with cross-domain solutions or NiFi is desirable.
• Experience writing scripting languages (Bash, Shell, Python, Perl). 
• Demonstrated experience working with a team to introduce and integrate new technologies into existing production environments. 
• Proficiency in working with applicable network devices to include routers and switches, gateways and hubs. 
• Experience with computer networking protocols including, but not limited to TCP, IP, UDP, HTTP, DHCP, and DNS.

Clearance Requirement:

• Must have a current/active TS/SCI with Poly

Physical Requirements:

• Must be able to remain in a stationary position at least 50% of the time.
• Needs to occasionally move about inside the office to access file cabinets, office machinery, etc.
• Constantly operate a computer and other office productivity machinery, such as, the copy machine/fax machine/computer/printer.

ManTech seeks an experienced and passionate, career and customer-oriented Linux System Administrator to join our team located in the Fort Meade, MD area.

Responsibilities include, but are not limited to:

• Design, engineer, and implement automated hardening scripts for internal servers adding scalability while circumventing manual process for new operating system rollout.
• Configure host-based intrusion detection systems.
• Monitor and troubleshoot/examine detected anomalies.
• Developed automation script adding new servers to IPA replacing human error and manual process
• Analyze system and security logs while responding to discovered real time events providing SOC status updates.
• Engineer ansible script automating creation of user accounts in IPA replacing manual process
• Review audits confirming hardening script successfully executed while checking for other vulnerabilities and/or configuration errors.
• Host design and review meetings providing security insight, team updates, goals, projections to branch management.

Minimum Qualifications:

• 7 year’s experience in systems administration of hardware and software in support of developing and testing of information technology systems 
• Experience with Linux administration
• Experience using Ansible or comparable tools
• Experience working with a team to introduce and integrate new technologies into existing production environments 
• Experience with integrated processing environments such as a Storage Area Network  

Preferred Qualifications:

• Experience with DevOps tools such as Docker, Kubernetes, SALT, Puppet desirable 
• Experience with cross-domain solutions or NiFi desirable for some positions 
• Experience writing scripting languages (Bash, Shell, Python, Perl) 
• Proficiency in working with applicable network devices to include routers and switches, gateways and hubs 
• Experience with computer networking protocols including, but not limited to TCP, IP, UDP, HTTP, DHCP, and DNS   
• Ability to handle stress and work under pressure
• Competence in computer operating systems

Clearance Requirement:

• Must have a current/active TS/SCI with Poly

Physical Requirements:

• Must be able to remain in a stationary position at least 50% of the time.
• Needs to occasionally move about inside the office to access file cabinets, office machinery, etc.
• Constantly operate a computer and other office productivity machinery, such as, the copy machine/fax machine/computer/printer.

**Description**
**Are you a tech enthusiast with a passion for ensuring the seamless operation of information system environments?**
Leidos Defense Systems Sector is looking for a skilled **Linux System Administrator** to join our team. In this role, you'll be in command of designing, maintaining, and enhancing our portfolio's architecture, ensuring compliance with information assurance requirements, and guaranteeing continuity of operations. You will work directly with software and radar engineers daily to build and maintain reliable information systems that enable the advancement of modern defense systems. Grow your career with us.
**If this sounds like the kind of environment where you can thrive, keep reading!**
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 sustainably. 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.
**Leidos Defense Systems Sector** 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. To explore and learn more, click here ( !
**Are you ready to make an impact? Share your resume with us today!**
**Primary Responsibilities**
+ Work primarily on Linux based systems to design, build, integrate, harden, deploy, and maintain bare metal and virtual clients, servers, and networked systems.
+ Develop solutions to complex technical issues that impact multiple IT disciplines.
+ Effectively use automated hardening and scanning tools such as Ansible and Nessus.
+ Perform system analysis for purposes of performance optimization, catastrophe mitigation, and security compliance.
+ Collaborate with software developers to ensure systems meet functional requirements.
+ Support IT security activities to include security compliance reviews and auditing requirements.
+ Perform software configuration management using software development repositories.
+ Potential for intermittent international travel to support system installs and maintenance. This may be a future need depending on the growth of the portfolio.
**Basic Qualifications**
+ Bachelor of Science in Technical field and 8-12 years of relevant work experience; equivalent years' or 12-16 years of relevant experience may be considered in lieu of a degree.
+ Must have 5+ years of recent direct System Administrator experience.
+ Must be a US citizen, possess and able to maintain an active DoD Secret clearance or be able to obtain and maintain a DoD Secret clearance is required for consideration.
+ **DoD Directive 8570 / 8140 Information Assurance Technical (IAT) Level II certification** . (Security+ CE, CCNA Security, CySA+, GICSP, GSEC, CND, SSCP)
+ Experience administering Linux Operating systems, Networking/Switch, and Virtualized Machines
+ Ability to create scripts to automate repetitive tasks on Linux.
+ Experience implementing NIST 800-53 control families.
+ Experience with core infrastructure services administration such as AD, DNS, DHCP, and File Server administration.
+ Experienced in deploying Operating System images in a variety of mediums (PXE-network, disk image, automated installation media with answer scripts).
+ Ability to collaborate within a team and independently with minimal supervision.
+ Perform research necessary to resolve complex technical problems
+ Administer Windows Operating systems
+ Willing and able to travel internationally as required to support system installation and maintenance.
+ Work will be performed on site in Huntsville, AL. Must be a resident of the North Alabama area or willing to relocate to the Huntsville - North Alabama, AL, area.
**Preferred Qualifications**
+ System Administrator experience in a similar sized organization.
+ Experienced in building and deploying DevSecOps systems.
+ Experienced in deploying Multifactorial Authentication Systems.
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:**
September 23, 2025
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 $89,700.00 - $162,150.00
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.
REQNUMBER: R-
All qualified applicants will receive consideration for employment without regard to race, color, religion, sex, sexual orientation, gender identity, national origin, disability or veteran status. Leidos will consider qualified applicants with criminal histories for employment in accordance with relevant Laws. Leidos is an equal opportunity employer/disability/vet.

**Description**
**Are you passionate about tackling intricate challenges?**
Leidos-Dynetics, within the Digital Modernization sector, is seeking a Linux System Administrator to ensure the secure and efficient operation of our Linux-based systems, while seamlessly integrating with other technologies within a high-traffic network environment. In this full-time, on-site role, you will collaborate closely with stakeholders to support a variety of programs. Expertise in both Linux and Windows technologies is essential.
**Location:** Your work will be performed in our Huntsville, AL office.
**Clearance:** You must currently hold an active Top Secret clearance to qualify for consideration (U.S. Citizenship required)
At Leidos-Dynetics, we recognize the value of having a high-performing workforce and are committed to providing opportunities for employees by encouraging career growth and movement across the enterprise. We view career development as a partnership between employees, managers, and the company with a focus on building skills and experiences through internal mobility. To support career development, we offer a variety of resources in addition to training and educational opportunities within an inclusive environment.
**What We Value:**
We're not just looking for technical expertise; we value a positive attitude, adaptability to changing priorities, and a commitment to getting the job done. Our ideal candidate is a reliable troubleshooter, adept at handling multiple priorities with excellent coping skills. Whether working independently or collaboratively, you're self-managed and customer-focused.
**Key Responsibilities:**
+ Maintain Both Linux and Windows servers and workstations.
+ Embrace new technologies to meet evolving requirements.
+ Provide onsite IT support.
+ Coordinate with the Information assurance team to meet compliance.
+ Maintain a robust virtual and physical environment.
+ Manage privileged access management.
+ Ensure the proper marking, handling, and storage of classified materials.
**Experience and Skills:**
+ Bachelor's Degree with 4+ years of relevant experience, additional experience may be considered in lieu of degree.
+ Minimum of 4 (Four) years of System Administrator experience.
+ Minimum of 2 (Two) years administering Linux operating systems with strong capability in administering **Red Hat Linux.**
+ **Active Top Secret Clearance**
+ **Current IAT II certification** (Security+ or equivalent)
+ Strong written and verbal communication skills.
+ Ability to interface effectively with security agencies, customers, and management.
+ Manage multiple networks in a dynamic, demanding environment.
+ Familiarity with Risk Management Framework requirements for Windows and Linux systems.
+ DoD Directive 8570 / 8140 Information Assurance Technical (IAT) Level II certification. (Security+ CE, CCNA Security, CySA+, GICSP, GSEC, CND, SSCP)
**Preferred Qualifications:**
+ Previous experience maintaining networks in classified environments.
+ Experience maintaining Linux environments.
+ Experience with Ansible.
+ RHCSA (Red Hat Certified System Administrator)
Come break things (in a good way). Then build them smarter.
We're the tech company everyone calls when things get weird. We don't wear capes (they're a safety hazard), but we do solve high-stakes problems with code, caffeine, and a healthy disregard for "how it's always been done."
**Original Posting:**
August 15, 2025
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 $89,700.00 - $162,150.00
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.
#Featuredjob
REQNUMBER: R-
All qualified applicants will receive consideration for employment without regard to race, color, religion, sex, sexual orientation, gender identity, national origin, disability or veteran status. Leidos will consider qualified applicants with criminal histories for employment in accordance with relevant Laws. Leidos is an equal opportunity employer/disability/vet.