Lead Senior Systems Administrator

General information

Requisition # R66220 Locations USA-VA-Chantilly Posting Date 02/19/2026 Security Clearance Required TS/SCI w/ Poly Remote Type Onsite Time Type Full time

Description & Requirements

Unlock the secrets of intelligence with MANTECH! Join a dynamic team at the forefront of national security, providing advanced solutions to government intelligence agencies. Since 1968, we’ve been solving the toughest challenges with groundbreaking tech. Explore thrilling projects in Digital Transformation, Cybersecurity, IT, Data Analytics and Software Development. Elevate your career and make a difference. Your adventure begins now—unleash your potential with MANTECH!

MANTECH seeks a motivated, mission-oriented Senior Systems Administrator to join our team in Chantilly, VA.

As the Lead Senior Systems Administrator, you will be responsible for providing a full range of Tier 2/3 IT support services and expertise to customer activities, as well as leading, mentoring, and coordinating with a team of System Administrators. You will play a key role in the management, optimization, and troubleshooting of our VMware virtualized environment and Active Directory infrastructure, ensuring seamless and reliable operations for the organization.  You will demonstrate knowledge and understanding of client and server operations and maintenance with Windows 10 and 11 environments and Windows Server 2016/2019, to include Active Directory, Domain Controllers, DNS, GPO’s, PKI, DHCP, VMware v8, Backup Architectures, Storage Management, and Auditing. 

Responsibilities include, but not limited to:

• Lead and supervise a team of system administrators (Windows/Linux/VMWare) and IT support staff.
• Design, implement, and maintain VMware vSphere environments, including vCenter, ESXi hosts, and virtual machines.
• Troubleshoot and resolve VMware-related issues, including performance bottlenecks, connectivity problems, and resource allocation.
• Manage, monitor, and troubleshoot Active Directory (AD) and Group Policy infrastructure.
• Administer and support user and group management, including security and distribution groups within Active Directory.
• Collaborate with other IT teams to manage system integration, configuration, and upgrades.
• Domestic Travel up to 25%

Minimum Qualifications:

• Bachelor’s Degree and 7 years’ experience, or high school diploma/GED and 13 years of relevant systems administration experience with 3 + years in a leadership role
• Experience in performing maintenance, repair, upgrade, and full life cycle support of hardware/software interfacing with the enterprise
• Knowledge of Windows file and folder permission & inheritance structure
• Experience in researching and ordering hardware/software to meet customer requirements
• Experience with client system security to include scans, patching, audit log review, and system health checks
• Experience in creating and maintaining comprehensive documentation for systems architecture