Senior Systems Administrator - Windows/Linux Dual-Stack Specialist

Mantech International Corporation • Fairmont, WV

48d • Onsite

About The Position

Transform the future of federal services with MANTECH! Join a vibrant, energetic team committed to enhancing national security and public services through innovative tech. Since 1968, we've partnered with Federal Civilian sectors to deliver impactful solutions. Engage in exciting projects in Digital Transformation, Cybersecurity, IT, Data Analytics and more. Ignite your career and drive change. Your journey starts now-innovate and excel with MANTECH! MANTECH seeks a motivated and customer-oriented Senior Systems Administrator - Windows/Linux Dual-Stack Specialist to join our team in Boulder, CO. or Fairmont WV This role is part of the Infrastructure Support (IS) team and is critical for maintaining the stability, integrity, and security of a high-impact large scale enterprise network infrastructure. The ideal candidate will be a proactive problem-solver with a strong background in network operations, security, and cloud services.

Requirements

• Bachelor's degree and 4+ years of experience in Systems Administration, with demonstrated expertise in both Windows Server and Enterprise Linux environments.
• Expert-level, hands-on experience in building, securing, and troubleshooting Windows Servers from scratch and designing complex Active Directory environments.
• Senior-level experience with Linux system administration, networking, security hardening, and scripting/automation tools.
• Proven working knowledge of U.S. Federal Government cybersecurity compliance standards, including FISMA, NIST Special Publications (especially 800-53/800-171), and Continuous Diagnostics and Mitigation (CDM) practices.
• Must be a U.S. Citizen and have a current/active Secret Security clearance.

Nice To Haves

• Microsoft Certified Systems Administrator/Engineer (MCSA/MCSE) or equivalent (e.g., Azure Administrator).
• Red Hat Certified Engineer (RHCE) or equivalent advanced Linux certification.
• CompTIA Security+ (or higher, e.g., CISSP, CISM, CASP+).
• Experience with container technologies such as Docker, Kubernetes, and/or OpenShift.
• Experience with enterprise tools such as Tenable and Microsoft System Center Configuration Manager (SCCM) or Microsoft Endpoint Configuration Manager (MECM).

Responsibilities

• Provide expertise in the full lifecycle management of Windows Server environments. This includes building, configuring, patching, and hardening Windows Server installations (e.g., 2019/2022) from bare-metal or virtual templates to meet all Federal Information Security Management Act (FISMA) High requirements.
• Design, deploy, and maintain complex Active Directory (AD) forests, domains, trusts, and replication topologies. Expertly manage Group Policy Objects (GPOs), DNS, DHCP, and Public Key Infrastructure (PKI) services. Manage and maintain virtualized environments (VMware vSphere/ESXi, Hyper-V) and support the administration of cloud platforms (e.g. Azure, AWS, Google, etc) utilized by the team.
• Manage and enforce privileged access management (PAM) solutions, user accounts, service accounts, and resource permissions in strict accordance with government security policies.
• Utilize scripting languages (e.g., Python, Bash, PowerShell) and configuration management tools (e.g., Ansible, Puppet) to automate repetitive tasks, configuration baselines, and deployment pipelines across both Windows and Linux environments.
• Lead efforts to integrate Linux systems into the overall IT architecture and support the migration of services and functions away from Windows platforms.

What This Job Offers

• Job Type: Full-time
• Career Level: Mid Level
• Industry: Professional, Scientific, and Technical Services
• Number of Employees: 5,001-10,000 employees