Windows Systems Administrator Security Clearance

Position: Windows Systems Administrator with Security Clearance
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- 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 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   
* Support and optimize SAN storage environments   
* Manage backup and recovery operations using Rubrik   
* Support and troubleshoot security platforms, including:

* Trellix ePO   
* 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   
* 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   
* 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 just maintain…