Windows Systems Administrator

** Description*
* ** Position Overview*
* 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 willbe 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'llOwn*
* + 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*
* + Support and optimize
** SAN storage environments*
* + Manage
** backup and recovery operations
** using Rubrik

+ Support and troubleshoot
** security platforms** , including:

+ TrellixePO

+ Rapid7

+ Security Onion IDS

+ Centrify

+ Perform
** deep-dive troubleshooting and root cause analysis
** across systems

+ Maintain
** system documentation, SOPs, and incident response procedures*
* + Identify and implement
** infrastructure improvements and automation opportunities*
* ** Environment Characteristics*
* +  
** Air-gapped / enclave networks*
* + 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*
* + Experienceoperatingin
** 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*
* + TrellixePO

+ Rapid7

+ Security Onion IDS

+ Centrify

+  
** Backup & Recovery*
* + Rubrik

+  
** Preferred*
* + Power Shell / Bash scripting

+

Experience with compliance frameworks (STIGs, RMF, NIST)

** Operational Expectations*
* + Support a
** 24/7 operational environment*
* + Participate in a
** rotational on-call schedule*
* + Must be able to
** respond (Return-to-Base) within 2 hours** , including travel if required

+ Support
** after-hours maintenance windows and incident response*
* ** What Sets This Role Apart*
* + Direct ownership of
** mission-critical systems supporting real-world operations*
* + Opportunity to work in
** secure, high-impact environments*
* + Exposure to both
** legacy infrastructure challenges and modernization efforts*
* + Ability to
** drive meaningful improvements** , not justmaintainstatus quo

** Who We're Looking Foran Engineer Who:*
* + Hasoperatedin
** cleared environments
** and understands the constraints

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

+ Doesn'twait for direction
- ** identifiesproblems and solves them*
* + Is trusted to handle
** high-pressure situations without supervision*
* + Brings both
** technical depth and operational accountability*
* ** Bottom Line*
* Ifyou'relooking for a role where:

+ Your work directly supports
** critical operations*
* + You have
** real ownership and responsibility*
* + And your impact is
** immediate and visible*
* If you're looking for comfort, keep scrolling. At Leidos, we outthink,…