3,426 System Administrator jobs in the United States

• Manage end-to-end patch management for both Microsoft Windows and Linux servers.
• Package patches and applications for deployment or uninstallation to support remediation efforts across both platforms.
• Diagnose and resolve complex patching issues, including failed deployments and dependency conflicts.
• Build, test, and deploy custom packages (e.g., MSI, RPM, DEB) for both Windows and Linux environments.
• Utilize Microsoft SCCM for Windows patch management, application deployment, and compliance reporting.
• Manage Linux patching through repository management, scheduling (e.g., cron), and custom package deployments.
• Leverage HCL BigFix for cross-platform patch deployment, compliance tracking, and reporting.
• Integrate and collaborate with Qualys Patch Module for vulnerability detection, prioritization, and remediation.
• Develop and maintain documentation for patch management processes, packaging procedures, troubleshooting steps, and deployment schedules.
• Work closely with security and compliance teams to address vulnerabilities and ensure timely remediation.
• Participate in audits and ensure patch management practices meet regulatory and organizational standards.
• Stay current with security advisories, patching best practices, and emerging technologies for both Windows and Linux platforms.

• 5+ years of experience administering both Microsoft Windows and Linux systems in a large enterprise environment.
• 3+ years of hands-on experience with patch management, including repository and package management for Linux and SCCM for Windows.
• Strong troubleshooting skills for diagnosing patch and dependency issues across both platforms.
• Experience building and deploying custom MSI, RPM, and DEB packages.
• Proficiency with HCL BigFix for patch deployment and compliance.
• Experience with Qualys Patch Module or similar vulnerability management tools.
• Solid understanding of Windows and Linux security, patching processes, and scheduling tools.

• Manage end-to-end patch management for both Microsoft Windows and Linux servers.
• Package patches and applications for deployment or uninstallation to support remediation efforts across both platforms.
• Diagnose and resolve complex patching issues, including failed deployments and dependency conflicts.
• Build, test, and deploy custom packages (e.g., MSI, RPM, DEB) for both Windows and Linux environments.
• Utilize Microsoft SCCM for Windows patch management, application deployment, and compliance reporting.
• Manage Linux patching through repository management, scheduling (e.g., cron), and custom package deployments.
• Leverage HCL BigFix for cross-platform patch deployment, compliance tracking, and reporting.
• Integrate and collaborate with Qualys Patch Module for vulnerability detection, prioritization, and remediation.
• Develop and maintain documentation for patch management processes, packaging procedures, troubleshooting steps, and deployment schedules.
• Work closely with security and compliance teams to address vulnerabilities and ensure timely remediation.
• Participate in audits and ensure patch management practices meet regulatory and organizational standards.
• Stay current with security advisories, patching best practices, and emerging technologies for both Windows and Linux platforms.

• 5+ years of experience administering both Microsoft Windows and Linux systems in a large enterprise environment.
• 3+ years of hands-on experience with patch management, including repository and package management for Linux and SCCM for Windows.
• Strong troubleshooting skills for diagnosing patch and dependency issues across both platforms.
• Experience building and deploying custom MSI, RPM, and DEB packages.
• Proficiency with HCL BigFix for patch deployment and compliance.
• Experience with Qualys Patch Module or similar vulnerability management tools.
• Solid understanding of Windows and Linux security, patching processes, and scheduling tools.

Position Summary George Butler Associates, Inc. is seeking an experienced and highly skilled IT Administrator to join our growing technology team. This role is ideal for a technical leader who thrives in server and hardware infrastructure, while also possessing the versatility to manage and support cloud services, primarily in Microsoft 365 and Azure environments. The ideal candidate will demonstrate both hands-on technical expertise and excellent communication skills, with the ability to lead initiatives, support end users, and collaborate cross-functionally. Responsibilities/Duties (including, But Are Not Limited To The Following) Core Infrastructure & Server Administration Administer and maintain physical and virtual servers (Windows Server, Hyper-V/VMware). Oversee server patching, backups, and lifecycle management. Monitor system performance and troubleshoot issues at the hardware and OS levels. Design and implement server upgrades, migrations, and high-availability setups. Hardware & Network Management Support IT infrastructure including desktops, laptops, and storage. Lead hardware procurement, asset inventory, and lifecycle planning. Ensure all hardware is configured securely and in compliance with company standards. Microsoft 365 & Azure Cloud Administration Manage and optimize Microsoft 365 environment: Exchange Online, SharePoint, OneDrive, Teams. Administer Azure AD, group policies, conditional access, and security baselines. Assist with identity, access, and licensing management across cloud services. Monitor service health, perform audits, and automate administrative tasks where possible. Qualifications Minimum Qualifications: Proficiency in Windows Server environments (2016/2019/2022). A degree in technology field or a minimum of 5 years’ experience in a similar position Strong communication and collaboration skills A foundational understanding of Networking Experience supporting a hybrid Active Directory and Azure AD environment. 2 years Azure and Entra ID experience The ability to make minor scripts in bash/powershell Understand and champion change management Ability to self-manage time and deliverables based on criticality Understanding of cybersecurity practices that may need to be adhered to Solid organizational skills (methodical/action plans/schedules/etc.) Ability to schedule and document own time management and reporting Positive and professional interpersonal skills Desired Qualifications Bachelor’s degree in computer science field 5 years’ experience in IT department with “master” understanding of technology stacks Designed/executed multiple back-up diagrams/plans into technical ecosystem Programming certifications, experience, and related course work Master level understanding of Change Management Proven track record of technology stack growth (within individual) as well as responsibilities Master level understanding of all technologies listed under the responsibilities and duties section within job description Proficient in all areas of communication (verbally/writing/etc.) with all levels of staff/leadership Proficient in following/providing detailed written/verbal instruction Master level abilities to problem-solve and reverse engineer complex technical issues Technical Skills M365 Administration Azure Administration Single Sign-On Veeam/VMware/Hyper-V Active Directory Intune Administration Documentation Low level networking (DHCP, DNS, Switches, Firewall…) Familiarity with the following SW: BIM (Revit), Bluebeam, Bentley, AutoCAD (a plus) #J-18808-Ljbffr

ManTech seeks a motivated, career and customer-oriented Network System Administrator III to join our team in Los Angeles, CA.

The primary function is working with Special Access Program (SAPs) and other classified networks supporting SMC Directorates and/or AFSPC Operational Units. The position will provide “day-to-day” support for Collateral, Sensitive Compartmented Information (SCI) and Special Access Program (SAP) activities.

Responsibilities include but are not limited to:

• Install, maintain, audit and support a secure MS Windows network environment and limited web/data application service.
• Maintain internet applications and protocols IP, TCP, HTTP, HTTPS, FTP, & SSL.
• Maintain file servers, Firewalls, network access, Security Monitoring Systems and system documentation as required.
• Interface with local customers and provide IT related support to quickly resolve problems.
• Perform periodic maintenance, hardware upgrades and replacement, firmware updates and system configuration changes. Perform scheduled tape backups on systems as required.
• Manage data backup library to include storage of tapes, disks and other magnetic media at the customer’s location and off-site storage facilities as required.
• Attend planning and requirements meetings with IT staff, Program Managers and customers as required.
   

Minimum Qualifications:

• Bachelor’s degree in a related area or 4 additional years of experience may be accepted in lieu of degree.
• 6+ years total related experience. 
• 4+ years of relevant SCI experience.
• Must meet position and certification requirements outlined in DoD Directive 8570.01-M for Information Assurance Technician Level 2 such as CompTIA Security + CE, within 6 months of the date of hire.
• Working knowledge of JAFAN 6/0, DCID/JAFAN 6/3, DCID/JAFAN 6/9, and Joint DODIIS/Cryptologic SCI Information Systems Security Standards, Common Criteria, and System Security Policy as they relate to C&A for Legacy systems.
• Must be familiar with security policy/manuals and the appropriate ICDs/JAFANs/DOD Manuals and other guiding policy documents.
   

Preferred Qualifications:

• 2+ years of SAP-related experience highly desired.
• Ability to work in a dynamic environment and effectively interact with numerous DOD, military/civilian personnel and industry partners.
• Working knowledge of Microsoft Office (Word, PowerPoint, and Excel).
• Possess a high degree of originality, creativity, initiative requiring minimal supervision.
• Requires travel within the organizational Area of Responsibility (AOR) (note - could be extensive and will include both air and ground transportation).

Clearance Requirements:

• Current Top-Secret Clearance with SCI Eligibility.
• Eligibility for access to Special Access Program.
• Information Willingness to submit to a polygraph.
   

Physical Requirements:

• Must be able to remain in a stationary position 50%.
• Needs to occasionally move about inside the office to access file cabinets, office machinery, etc.
• Constantly operates a computer and other office productivity machinery, such as a calculator, copy machine and computer printer.
• Frequently communicates with co-workers, management and customers, which may involve delivering presentations. Must be able to exchange accurate information in these situations.

ManTech seeks a motivated, career and customer-oriented Network System Administrator III to join our team in Los Angeles, CA.

The primary function is working with Special Access Program (SAPs) and other classified networks supporting SMC Directorates and/or AFSPC Operational Units. The position will provide “day-to-day” support for Collateral, Sensitive Compartmented Information (SCI) and Special Access Program (SAP) activities.

Responsibilities include but are not limited to:

• Install, maintain, audit and support a secure MS Windows network environment and limited web/data application service.
• Maintain internet applications and protocols IP, TCP, HTTP, HTTPS, FTP, & SSL.
• Maintain file servers, Firewalls, network access, Security Monitoring Systems and system documentation as required.
• Interface with local customers and provide IT related support to quickly resolve problems.
• Perform periodic maintenance, hardware upgrades and replacement, firmware updates and system configuration changes. Perform scheduled tape backups on systems as required.
• Manage data backup library to include storage of tapes, disks and other magnetic media at the customer’s location and off-site storage facilities as required.
• Attend planning and requirements meetings with IT staff, Program Managers and customers as required.
   

Minimum Qualifications:

• Bachelor’s degree in a related area or 4 additional years of experience may be accepted in lieu of degree.
• 6+ years total related experience. 
• 4+ years of relevant SCI experience.
• Must meet position and certification requirements outlined in DoD Directive 8570.01-M for Information Assurance Technician Level 2 such as CompTIA Security + CE, within 6 months of the date of hire.
• Working knowledge of JAFAN 6/0, DCID/JAFAN 6/3, DCID/JAFAN 6/9, and Joint DODIIS/Cryptologic SCI Information Systems Security Standards, Common Criteria, and System Security Policy as they relate to C&A for Legacy systems.
• Must be familiar with security policy/manuals and the appropriate ICDs/JAFANs/DOD Manuals and other guiding policy documents.
   

Preferred Qualifications:

• 2+ years of SAP-related experience highly desired.
• Ability to work in a dynamic environment and effectively interact with numerous DOD, military/civilian personnel and industry partners.
• Working knowledge of Microsoft Office (Word, PowerPoint, and Excel).
• Possess a high degree of originality, creativity, initiative requiring minimal supervision.
• Requires travel within the organizational Area of Responsibility (AOR) (note - could be extensive and will include both air and ground transportation).

Clearance Requirements:

• Current Top-Secret Clearance with SCI Eligibility.
• Eligibility for access to Special Access Program.
• Information Willingness to submit to a polygraph.
   

Physical Requirements:

• Must be able to remain in a stationary position 50%.
• Needs to occasionally move about inside the office to access file cabinets, office machinery, etc.
• Constantly operates a computer and other office productivity machinery, such as a calculator, copy machine and computer printer.
• Frequently communicates with co-workers, management and customers, which may involve delivering presentations. Must be able to exchange accurate information in these situations.

ManTech seeks a motivated, career and customer-oriented Network System Administrator III to join our team in Los Angeles, CA.

The primary function is working with Special Access Program (SAPs) and other classified networks supporting SMC Directorates and/or AFSPC Operational Units. The position will provide "day-to-day" support for Collateral, Sensitive Compartmented Information (SCI) and Special Access Program (SAP) activities.

Responsibilities include but are not limited to:

• Install, maintain, audit and support a secure MS Windows network environment and limited web/data application service.

• Maintain internet applications and protocols IP, TCP, HTTP, HTTPS, FTP, & SSL.

• Maintain file servers, Firewalls, network access, Security Monitoring Systems and system documentation as required.

• Interface with local customers and provide IT related support to quickly resolve problems.

• Perform periodic maintenance, hardware upgrades and replacement, firmware updates and system configuration changes. Perform scheduled tape backups on systems as required.

• Manage data backup library to include storage of tapes, disks and other magnetic media at the customer's location and off-site storage facilities as required.

• Attend planning and requirements meetings with IT staff, Program Managers and customers as required.

Minimum Qualifications:

• Bachelor's degree in a related area or 4 additional years of experience may be accepted in lieu of degree.

• 6+ years total related experience.

• 4+ years of relevant SCI experience.

• Must meet position and certification requirements outlined in DoD Directive 8570.01-M for Information Assurance Technician Level 2 such as CompTIA Security + CE, within 6 months of the date of hire.

• Working knowledge of JAFAN 6/0, DCID/JAFAN 6/3, DCID/JAFAN 6/9, and Joint DODIIS/Cryptologic SCI Information Systems Security Standards, Common Criteria, and System Security Policy as they relate to C&A for Legacy systems.

• Must be familiar with security policy/manuals and the appropriate ICDs/JAFANs/DOD Manuals and other guiding policy documents.

Preferred Qualifications:

• 2+ years of SAP-related experience highly desired.

• Ability to work in a dynamic environment and effectively interact with numerous DOD, military/civilian personnel and industry partners.

• Working knowledge of Microsoft Office (Word, PowerPoint, and Excel).

• Possess a high degree of originality, creativity, initiative requiring minimal supervision.

• Requires travel within the organizational Area of Responsibility (AOR) (note - could be extensive and will include both air and ground transportation).

Clearance Requirements:

• Current Top-Secret Clearance with SCI Eligibility.

• Eligibility for access to Special Access Program.

• Information Willingness to submit to a polygraph.

Physical Requirements:

• Must be able to remain in a stationary position 50%.

• Needs to occasionally move about inside the office to access file cabinets, office machinery, etc.

• Constantly operates a computer and other office productivity machinery, such as a calculator, copy machine and computer printer.

• Frequently communicates with co-workers, management and customers, which may involve delivering presentations. Must be able to exchange accurate information in these situations.

ManTech International Corporation, as well as its subsidiaries proactively fulfills its role as an equal opportunity employer. We do not discriminate against any employee or applicant for employment. All qualified applicants will receive consideration for employment without regard to race, color, religion, sex, sexual orientation, gender identity, national origin, disability, or status as a protected veteran.

If you are a qualified individual with a disability and require a reasonable accommodation to apply for a position with ManTech through its online applicant system, please email us at and provide your name and contact information.

• Install, maintain, audit and support a secure MS Windows network environment and limited web/data application service.
• Maintain internet applications and protocols IP, TCP, HTTP, HTTPS, FTP, & SSL.
• Maintain file servers, Firewalls, network access, Security Monitoring Systems and system documentation as required.
• Interface with local customers and provide IT related support to quickly resolve problems.
• Perform periodic maintenance, hardware upgrades and replacement, firmware updates and system configuration changes. Perform scheduled tape backups on systems as required.
• Manage data backup library to include storage of tapes, disks and other magnetic media at the customer's location and off-site storage facilities as required.
• Attend planning and requirements meetings with IT staff, Program Managers and customers as required.

• Bachelor's degree in a related area or 4 additional years of experience may be accepted in lieu of degree.
• 6+ years total related experience.
• 4+ years of relevant SCI experience.
• Must meet position and certification requirements outlined in DoD Directive 8570.01-M for Information Assurance Technician Level 2 such as CompTIA Security + CE, within 6 months of the date of hire.
• Working knowledge of JAFAN 6/0, DCID/JAFAN 6/3, DCID/JAFAN 6/9, and Joint DODIIS/Cryptologic SCI Information Systems Security Standards, Common Criteria, and System Security Policy as they relate to C&A for Legacy systems.
• Must be familiar with security policy/manuals and the appropriate ICDs/JAFANs/DOD Manuals and other guiding policy documents.

• 2+ years of SAP-related experience highly desired.
• Ability to work in a dynamic environment and effectively interact with numerous DOD, military/civilian personnel and industry partners.
• Working knowledge of Microsoft Office (Word, PowerPoint, and Excel).
• Possess a high degree of originality, creativity, initiative requiring minimal supervision.
• Requires travel within the organizational Area of Responsibility (AOR) (note - could be extensive and will include both air and ground transportation).

• Current Top-Secret Clearance with SCI Eligibility.
• Eligibility for access to Special Access Program.
• Information Willingness to submit to a polygraph.

• Must be able to remain in a stationary position 50%.
• Needs to occasionally move about inside the office to access file cabinets, office machinery, etc.
• Constantly operates a computer and other office productivity machinery, such as a calculator, copy machine and computer printer.
• Frequently communicates with co-workers, management and customers, which may involve delivering presentations. Must be able to exchange accurate information in these situations.

ManTech seeks a motivated, career and customer-oriented Network System Administrator III to join our team in Los Angeles, CA. The primary function is working with Special Access Program (SAPs) and other classified networks supporting SMC Directorates and/or AFSPC Operational Units. The position will provide “day-to-day” support for Collateral, Sensitive Compartmented Information (SCI) and Special Access Program (SAP) activities. Responsibilities include but are not limited to: Install, maintain, audit and support a secure MS Windows network environment and limited web/data application service. Maintain internet applications and protocols IP, TCP, HTTP, HTTPS, FTP, & SSL. Maintain file servers, Firewalls, network access, Security Monitoring Systems and system documentation as required. Interface with local customers and provide IT related support to quickly resolve problems. Perform periodic maintenance, hardware upgrades and replacement, firmware updates and system configuration changes. Perform scheduled tape backups on systems as required. Manage data backup library to include storage of tapes, disks and other magnetic media at the customer’s location and off-site storage facilities as required. Attend planning and requirements meetings with IT staff, Program Managers and customers as required. Minimum Qualifications: Bachelor’s degree in a related area or 4 additional years of experience may be accepted in lieu of degree. 6 years total related experience. 4 years of relevant SCI experience. Must meet position and certification requirements outlined in DoD Directive 8570.01-M for Information Assurance Technician Level 2 such as CompTIA Security CE, within 6 months of the date of hire. Working knowledge of JAFAN 6/0, DCID/JAFAN 6/3, DCID/JAFAN 6/9, and Joint DODIIS/Cryptologic SCI Information Systems Security Standards, Common Criteria, and System Security Policy as they relate to C&A for Legacy systems. Must be familiar with security policy/manuals and the appropriate ICDs/JAFANs/DOD Manuals and other guiding policy documents. Preferred Qualifications: 2 years of SAP-related experience highly desired. Ability to work in a dynamic environment and effectively interact with numerous DOD, military/civilian personnel and industry partners. Working knowledge of Microsoft Office (Word, PowerPoint, and Excel). Possess a high degree of originality, creativity, initiative requiring minimal supervision. Requires travel within the organizational Area of Responsibility (AOR) (note - could be extensive and will include both air and ground transportation). Clearance Requirements: Current Top-Secret Clearance with SCI Eligibility. Eligibility for access to Special Access Program. Information Willingness to submit to a polygraph. Physical Requirements: Must be able to remain in a stationary position 50%. Needs to occasionally move about inside the office to access file cabinets, office machinery, etc. Constantly operates a computer and other office productivity machinery, such as a calculator, copy machine and computer printer. Frequently communicates with co-workers, management and customers, which may involve delivering presentations. Must be able to exchange accurate information in these situations.