Windows Systems Administrator

Leidos Inc; Chantilly (VA); On-site; USD 140,000 - 190,000; Full time

Job summary

Leidos is seeking a Senior Infrastructure Engineer to support mission-critical enclave environments across on-prem VMware and AWS cloud, in a high-security, high-availability ecosystem in Chantilly, Virginia. You will own, stabilize, and improve a hybrid infrastructure, driving reliability and performance forward in a fast-paced, validated setting.

This role requires deep hands-on expertise in Windows and virtualization, Active Directory, VMware, SCCM/WSUS, Exchange, and security tooling, with

Qualifications

• Active TS/SCI with Poly clearance required.
• Experience in Windows enterprise environments and high-availability systems.
• Ability to own and operate complex hybrid environments (on-prem + cloud).

Responsibilities

• Administer and maintain Windows-based infrastructure across enclave environments.
• Manage VMware vCenter / ESXi performance and VM lifecycle.
• Support AWS cloud infrastructure (EC2, VPC, storage, IAM).
• Maintain Active Directory, Group Policy, and identity systems.
• Oversee patching and system compliance via WSUS and SCCM.
• Administer Exchange and Citrix environments.
• Maintain DNS, networking, and core infra services.
• Support SAN storage environments and backup/recovery (Rubrik).
• Support and troubleshoot security platforms (e.g., Rapid7, Security Onion, Centrify).
• Perform deep-dive troubleshooting and root-cause analysis; maintain system docs and incident procedures.
• Identify and implement infrastructure improvements and automation opportunities.

Skills

High-security environment

Independent ownership

Troubleshooting

Windows enterprise experience

Tools

VMware vCenter / ESXi

AWS (EC2, VPC, storage, IAM basics)

Active Directory

SCCM / WSUS

Microsoft Exchange

Citrix

Rubrik

Security tooling (Rapid7, Security Onion, Centrify)

Job description

Description

We are seeking aSenior Infrastructure Engineerto support andoperatemission-critical, enclave-based environmentsacrosson-premises VMware infrastructure and AWS cloud.

This role sits at the center of ahigh-security, high-availability ecosystem, supporting systems wheredowntime has real operational impact. You willbe responsible forowning, stabilizing, and improvinga complex hybrid environment consisting of bothlegacy and modern platforms.

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

Clearance Requirement

• Active TS/SCI with Poly security clearancerequired

• Must be eligible to work inrestricted / air-gapped environments

WhatYou'llOwn

• Twostandalone/enclave Windows domains

• On-prem VMware-based infrastructure

• AWS-hosted environment

• A24/7 mission-critical system footprint

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

• Environments withlimited external connectivity and strict security controls

Key Responsibilities

• Administer andmaintainWindows-based infrastructureacross enclave environments

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

• SupportAWS cloud infrastructure(EC2, VPC, storage, IAM fundamentals)

• Maintain and troubleshootActive Directory, Group Policy, and identity systems

• Overseepatching and system compliancevia WSUS and SCCM

• AdministerMicrosoft ExchangeandCitrix environments

• MaintainDNS, networking, and core infrastructure services

• Support andoptimizeSAN storage environments

• Managebackup and recovery operationsusing Rubrik

• Support and troubleshootsecurity platforms, including:

• TrellixePO

• Rapid7

• Security Onion IDS

• Centrify

• Performdeep-dive troubleshooting and root cause analysisacross systems

• Maintainsystem documentation, SOPs, and incident response procedures

• Identifyand implementinfrastructure improvements and automation opportunities

Environment Characteristics

• Air-gapped / enclave networks

• Hybridon-prem (VMware) + AWS cloud

• Legacy mission systemswith modernization constraints

• Security-first architecture withstrict compliance requirements

• High uptime expectationswith minimal tolerance for disruption

Required Qualifications

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

• Active TS/SCI with Poly

• Strong experience supportingWindows enterprise environments

• Proven experience inhigh-availability / mission-critical systems

• Experienceoperatinginrestricted, regulated, or air-gapped environments

• Strong troubleshooting skills acrossOS, virtualization, networking, and storage layers

• Ability to work independently andtake 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

• TrellixePO

• Rapid7

• Security Onion IDS

• Centrify

• Backup & Recovery

• Rubrik

Preferred

• PowerShell / Bash scripting

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

Operational Expectations

• Support a24/7 operational environment

• Participate in arotational on-call schedule

• Must be able torespond (Return-to-Base) within 2 hours, including travel ifrequired

• Supportafter-hours maintenance windows and incident response

What Sets This Role Apart

• Direct ownership ofmission-critical systems supporting real-world operations

• Opportunity to work insecure, high-impact environments

• Exposure to bothlegacy infrastructure challenges and modernization efforts

• Ability todrive meaningful improvements, not justmaintainstatus quo

WhoWe'reLooking Foran Engineer Who:

• Hasoperatedincleared environmentsand understands the constraints

• Can walk into acomplex, imperfect systemand make it better

• Doesn'twait for direction-identifiesproblems and solves them

• Is trusted to handlehigh-pressure situations without supervision

• Brings bothtechnical depth and operational accountability

Bottom Line

If you're looking for a role where:

• Your work directly supportscritical operations

• You havereal ownership and responsibility

• And your impact isimmediate and visible

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.

About Leidos

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.

Pay and Benefits

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.

Securing Your Data

Beware of fake employment opportunities using Leidos' name. Leidos will never ask you to provide payment-related information during any part of the employment application process (i.e., ask you for money), nor will Leidos ever advance money as part of the hiring process (i.e., send you a check or money order before doing any work). Further, Leidos will only communicate with you through emails that are generated by the Leidos.com automated system - never from free commercial services (e.g., Gmail, Yahoo, Hotmail) or via WhatsApp, Telegram, etc. If you received an email purporting to be from Leidos that asks for payment-related information or any other personal information (e.g., about you or your previous employer), and you are concerned about its legitimacy, please make us aware immediately by emailing us at [e-mail].

If you believe you are the victim of a scam, contact your local law enforcement and report the incident to the U.S. Federal Trade Commission.

Commitment to Non-Discrimination

All qualified applicants will receive consideration for employment without regard to sex, race, ethnicity, age, national origin, citizenship, religion, physical or mental disability, medical condition, genetic information, pregnancy, family structure, marital status, ancestry, domestic partner status, sexual orientation, gender identity or expression, veteran or military status, or any other basis prohibited by law. Leidos will also consider for employment qualified applicants with criminal histories consistent with relevant laws.