Windows Systems Administrator

Description

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
.

• Active TS/SCI with Poly security clearance required

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

• 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

• 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

• 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

• 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

• 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

• Power Shell / Bash scripting

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

• 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

• 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

• Hasoperatedin
  cleared environments
  and understands the constraints

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

• Doesn'twait for direction
  - identifies problems and solves them

• Is trusted to handle
  high-pressure situations without supervision

• Brings both
  technical depth and operational accountability

If you're looking 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, 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.

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

Pay and benefits are fundamental to any career…