Windows Systems Administrator

We are seeking a Senior Infrastructure Engineer to support and operate mission-critical, enclave-based environments across on-premises VMware infrastructure and AWS cloud.

This role sits at the center of a high-security, high-availability ecosystem, supporting systems where downtime has real operational impact. You will be responsible for owning, stabilizing, and improving a complex hybrid environment consisting of both legacy and modern platforms.

This is not a passive support role-this is for someone who can step in, take control of the environment, and drive reliability and performance forward.

Clearance Requirement

• Active TS/SCI with Poly security clearance required

• Must be eligible to work in restricted / air-gapped environments

What You’ll Own

• Two standalone/enclave Windows domains:

• On-prem VMware-based infrastructure

• AWS-hosted environment

• A 24/7 mission-critical system footprint

• Core enterprise services: identity, storage, compute, backup, and security tooling

• Environments with limited external connectivity and strict security controls

Key Responsibilities

• Administer and maintain Windows-based infrastructure across enclave environments

• Manage VMware vCenter / ESXi (host performance, VM lifecycle, resource optimization)

• Support AWS cloud infrastructure (EC2, VPC, storage, IAM fundamentals)

• Maintain and troubleshoot Active Directory, Group Policy, and identity systems

• Oversee patching and system compliance via WSUS and SCCM

• Administer Microsoft Exchange and Citrix environments

• Maintain DNS, networking, and core infrastructure services

• Hybrid on-prem (VMware) + AWS cloud

• Legacy mission systems with modernization constraints

• Security-first architecture with strict compliance requirements

• High uptime expectations with minimal tolerance for disruption

Required Qualifications

• Must have at least 12 years of experience in systems engineering or infrastructure engineering

• Active TS/SCI with Poly

• Strong experience supporting Windows enterprise environments

• Proven experience in high-availability / mission-critical systems

• Experience operating in restricted, regulated, or air-gapped environments

• Strong troubleshooting skills across OS, virtualization, networking, and storage layers

• Ability to work independently and take ownership of complex systems

Core Technical Expertise

• Operating Systems

• Windows Server (2016/2019/2022)

• Windows 11

• Linux (Rocky Linux, Red Hat)

• Virtualization & Cloud

• VMware vCenter / ESXi

• AWS (EC2, VPC, storage, IAM basics)

• Core Infrastructure

• Active Directory & Group Policy

• DNS / networking fundamentals

• SAN Storage

• Systems Management

• SCCM, WSUS

• Microsoft Exchange

• Citrix

• Security Tooling

• Trellix ePO

• Rapid7

• Security Onion IDS

• Centrify

• Backup & Recovery

• Rubrik

• Preferred

• PowerShell / Bash scripting

• Experience with compliance frameworks (STIGs, RMF, NIST)

Operational Expectations

• Support a 24/7 operational environment, * Has operated in cleared environments and understands the constraints

• Can walk into a complex, imperfect system and make it better

• Doesn’t wait for direction-identifies problems and solves them

• Is trusted to handle high-pressure situations without supervision

• Brings both technical depth and operational accountability

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 .

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 .