Administer, maintain, secure, and optimize Windows-based infrastructure in a classified federal environment. Responsibilities include managing Active Directory, Group Policy, DNS, DHCP, patching, vulnerability remediation, virtualization, system monitoring, configuration management, Tier II/III troubleshooting, scripting automation, and compliance with DISA STIGs. The role also supports enterprise applications and services, documents operational procedures, coordinates with technical teams, and mentors junior administrators.
Description
The Senior System Administrator will support the administration, maintenance, security, and optimization of mission-critical Windows-based infrastructure in a secure federal environment. This role requires an experienced administrator with strong technical troubleshooting skills, a proactive approach to system performance and reliability, and the ability to operate effectively in environments requiring an active Top Secret/Sensitive Compartmented Information (TS/SCI) clearance.
What You Will Do
* Administer, maintain, and troubleshoot Windows Server and Windows desktop environments across classified or secure enterprise networks.
* Manage Active Directory, Group Policy Objects, DNS, DHCP, user accounts, security groups, organizational units, and domain controller operations.
* Perform system monitoring, performance tuning, capacity planning, patch management, vulnerability remediation, and root cause analysis.
* Install, configure, upgrade, and support operating systems, enterprise applications, server hardware, and virtualized infrastructure.
* Develop, maintain, and execute standard operating procedures for system builds, configuration baselines, software deployments, and maintenance activities.
* Support compliance with applicable security standards, including DISA STIGs, vulnerability scan remediation, change control, and configuration management requirements.
* Provide Tier II/III support for escalated incidents involving servers, workstations, applications, authentication, permissions, and enterprise services.
* Use PowerShell or other scripting tools to automate routine administration, reporting, software deployment, and maintenance tasks.
* Coordinate with cybersecurity, network, engineering, and help desk teams to support secure and reliable system operations.
* Mentor junior administrators and provide technical guidance on troubleshooting, documentation, and operational best practices.
What We Expect of You
* Active TS/SCI clearance is required at the time of hire.
* U.S. citizenship is required due to federal contract and clearance requirements.
* 8+ years of relevant experience in systems administration, infrastructure operations, or enterprise IT support.
* Strong hands-on experience administering Microsoft Windows Server and Windows workstation environments.
* Experience with Active Directory, Group Policy, DNS, DHCP, domain services, user permissions, and enterprise authentication.
* Experience with patching, vulnerability remediation, system hardening, and applying secure configuration baselines.
* Ability to troubleshoot complex hardware, software, operating system, authentication, and network-related issues.
* Experience supporting secure or classified environments, including adherence to change management and documentation requirements.
* Strong written and verbal communication skills, with the ability to document procedures and brief technical status to stakeholders.
* DoD 8570/8140 IAT Level II certification, such as Security+ CE, or the ability to obtain/maintain required compliance certification, is a plus.
* Experience with VMware, Hyper-V, Nutanix, or other enterprise virtualization platforms, is a plus.
* Experience with Microsoft Endpoint Configuration Manager, SCCM, MECM, PDQ Deploy, or similar software deployment tools, is a plus.
* Familiarity with ACAS/Nessus vulnerability findings, HBSS/ESS tools, STIG Viewer, and remediation tracking, is a plus.
* Experience creating or maintaining Windows images, deployment packages, and automated build processes, is a plus.
* Working knowledge of backup and recovery processes, disaster recovery planning, and continuity of operations support, is a plus.
* Experience supporting IIS, file services, print services, certificate services, or other Microsoft enterprise services, is a plus. Pay range: $175,000 - $220,000 depending on experience and skill set Benefits overview: https://cdw.benefit-info.com/ Salary ranges may be subject to geographic differentials
* CDW is committed to being an AI-fluent organization
* We're looking for people who bring curiosity, a learner's mindset, and a willingness to engage with ever-evolving technology and tools. We value adopting AI as a partner, openness to experimentation, and a shared interest in learning together on AI. Our goal is to create a culture where AI enhances- not replaces- human creativity and decision-making. You don't need to be an expert today; what matters is your readiness to explore, adapt, and grow with us as we integrate AI responsibly and effectively into our work.Additionally, CDW is committed to fostering an equitable, transparent, and respectful hiring process for all applicants. During our application process, our goal is to understand your experience, strengths, skills, and qualifications. As an AI forward company, we see AI not just as a tool, but as a catalyst for new ways of thinking, creating, and communicating. We encourage candidates to embrace an AI mindset, one that's curious, adaptive, and ready to explore what's possible. We welcome thoughtful use of AI to expand your perspective and elevate how you share your story, while ensuring your application remains rooted in your own background, judgment, and voice.
* About Us
* CDW is a Fortune 500 technology solutions provider that helps businesses, government, education, and healthcare organizations achieve what's possible through technology. What makes CDW different isn't just what we do- it's how we do it. At CDW we act as one- building trust, speaking candidly, and working together to achieve more. We play to win- focusing on what matters most and delivering for our customers. And we think forward- staying curious, moving fast, and continuously learning. We believe meaningful work happens when people feel supported, heard, and empowered to contribute. That's why we think of ourselves as coworkers, not just employees- working together to solve complex challenges and deliver real impact for our customers and communities. As a full-stack, full-lifecycle technology partner, CDW brings deep expertise, strong relationships, and broad industry knowledge to help turn ideas into outcomes. When you join CDW, you become part of a collaborative environment where your work matters, your growth is supported, and your contributions help shape what's next. Together, we deliver the full promise of what technology can do.
* Together, we Make Amazing Happen.
* CDW is an equal opportunity employer. All qualified applicants will receive consideration for employment without regards to race, color, religion, sex, sexual orientation, gender identity, national origin, disability status, protected veteran status or any other basis prohibited by state and local law.
The Senior System Administrator will support the administration, maintenance, security, and optimization of mission-critical Windows-based infrastructure in a secure federal environment. This role requires an experienced administrator with strong technical troubleshooting skills, a proactive approach to system performance and reliability, and the ability to operate effectively in environments requiring an active Top Secret/Sensitive Compartmented Information (TS/SCI) clearance.
What You Will Do
* Administer, maintain, and troubleshoot Windows Server and Windows desktop environments across classified or secure enterprise networks.
* Manage Active Directory, Group Policy Objects, DNS, DHCP, user accounts, security groups, organizational units, and domain controller operations.
* Perform system monitoring, performance tuning, capacity planning, patch management, vulnerability remediation, and root cause analysis.
* Install, configure, upgrade, and support operating systems, enterprise applications, server hardware, and virtualized infrastructure.
* Develop, maintain, and execute standard operating procedures for system builds, configuration baselines, software deployments, and maintenance activities.
* Support compliance with applicable security standards, including DISA STIGs, vulnerability scan remediation, change control, and configuration management requirements.
* Provide Tier II/III support for escalated incidents involving servers, workstations, applications, authentication, permissions, and enterprise services.
* Use PowerShell or other scripting tools to automate routine administration, reporting, software deployment, and maintenance tasks.
* Coordinate with cybersecurity, network, engineering, and help desk teams to support secure and reliable system operations.
* Mentor junior administrators and provide technical guidance on troubleshooting, documentation, and operational best practices.
What We Expect of You
* Active TS/SCI clearance is required at the time of hire.
* U.S. citizenship is required due to federal contract and clearance requirements.
* 8+ years of relevant experience in systems administration, infrastructure operations, or enterprise IT support.
* Strong hands-on experience administering Microsoft Windows Server and Windows workstation environments.
* Experience with Active Directory, Group Policy, DNS, DHCP, domain services, user permissions, and enterprise authentication.
* Experience with patching, vulnerability remediation, system hardening, and applying secure configuration baselines.
* Ability to troubleshoot complex hardware, software, operating system, authentication, and network-related issues.
* Experience supporting secure or classified environments, including adherence to change management and documentation requirements.
* Strong written and verbal communication skills, with the ability to document procedures and brief technical status to stakeholders.
* DoD 8570/8140 IAT Level II certification, such as Security+ CE, or the ability to obtain/maintain required compliance certification, is a plus.
* Experience with VMware, Hyper-V, Nutanix, or other enterprise virtualization platforms, is a plus.
* Experience with Microsoft Endpoint Configuration Manager, SCCM, MECM, PDQ Deploy, or similar software deployment tools, is a plus.
* Familiarity with ACAS/Nessus vulnerability findings, HBSS/ESS tools, STIG Viewer, and remediation tracking, is a plus.
* Experience creating or maintaining Windows images, deployment packages, and automated build processes, is a plus.
* Working knowledge of backup and recovery processes, disaster recovery planning, and continuity of operations support, is a plus.
* Experience supporting IIS, file services, print services, certificate services, or other Microsoft enterprise services, is a plus. Pay range: $175,000 - $220,000 depending on experience and skill set Benefits overview: https://cdw.benefit-info.com/ Salary ranges may be subject to geographic differentials
* CDW is committed to being an AI-fluent organization
* We're looking for people who bring curiosity, a learner's mindset, and a willingness to engage with ever-evolving technology and tools. We value adopting AI as a partner, openness to experimentation, and a shared interest in learning together on AI. Our goal is to create a culture where AI enhances- not replaces- human creativity and decision-making. You don't need to be an expert today; what matters is your readiness to explore, adapt, and grow with us as we integrate AI responsibly and effectively into our work.Additionally, CDW is committed to fostering an equitable, transparent, and respectful hiring process for all applicants. During our application process, our goal is to understand your experience, strengths, skills, and qualifications. As an AI forward company, we see AI not just as a tool, but as a catalyst for new ways of thinking, creating, and communicating. We encourage candidates to embrace an AI mindset, one that's curious, adaptive, and ready to explore what's possible. We welcome thoughtful use of AI to expand your perspective and elevate how you share your story, while ensuring your application remains rooted in your own background, judgment, and voice.
* About Us
* CDW is a Fortune 500 technology solutions provider that helps businesses, government, education, and healthcare organizations achieve what's possible through technology. What makes CDW different isn't just what we do- it's how we do it. At CDW we act as one- building trust, speaking candidly, and working together to achieve more. We play to win- focusing on what matters most and delivering for our customers. And we think forward- staying curious, moving fast, and continuously learning. We believe meaningful work happens when people feel supported, heard, and empowered to contribute. That's why we think of ourselves as coworkers, not just employees- working together to solve complex challenges and deliver real impact for our customers and communities. As a full-stack, full-lifecycle technology partner, CDW brings deep expertise, strong relationships, and broad industry knowledge to help turn ideas into outcomes. When you join CDW, you become part of a collaborative environment where your work matters, your growth is supported, and your contributions help shape what's next. Together, we deliver the full promise of what technology can do.
* Together, we Make Amazing Happen.
* CDW is an equal opportunity employer. All qualified applicants will receive consideration for employment without regards to race, color, religion, sex, sexual orientation, gender identity, national origin, disability status, protected veteran status or any other basis prohibited by state and local law.
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