> Markdown version of [/jobs/ext/531177-senior-system-administrator-windows-server-active-directory](https://www.wearedevelopers.com/jobs/ext/531177-senior-system-administrator-windows-server-active-directory). Every page supports `.md` or `Accept: text/markdown`. Links point to the HTML versions so they work for humans too. Agent guide: [/agents.md](https://www.wearedevelopers.com/agents.md). --- # Senior System Administrator - Windows Server & Active Directory - **Company:** JMA Wireless - **Location:** Syracuse, NY, United States - **Experience:** Expert - **Salary:** $120,000.0 - $140,000.0 - **Contract:** Permanent contract - **Skills:** Microsoft Access, Microsoft Windows, Active Directory, Domain Controllers, Microsoft Azure, Microsoft Online Services, Data Stores, Dynamic Host Configuration Protocol, Disaster Recovery, Domain Name System (DNS), Multi-Factor Authentication, VMware ESX Servers, Virtual Private Networks (VPN), Kerberos (Protocol), Microsoft Office, Windows Servers, Networking Basics, NT LAN Manager, Public Key Infrastructure, Windows PowerShell, Role-Based Access Control, Azure Active Directory, Zero Trust Network Access, Runbook, Microsoft SharePoint, Virtual Local Area Networks, Virtualization Technology, VMware Virtualization, VMware VSphere, Data Logging, Scripting, Load Balancing, Virtual Environment, Firewalls (Computer Science), Microsoft InTune, Microsoft Onedrive, Information Technology, Vcenter, Vmware - **Published:** June 10, 2026 - **Apply:** https://www.indeed.com/viewjob?jk=9ff3f8116b42c3a5 ## About the Role Do you have experience in vCenter?, Do you have a Bachelor's degree?, * 6+ years of system administration experience, including senior-level, hands-on Active Directory and Windows Server administration in production. * Expert working knowledge of Group Policy, DNS, DHCP, PKI, and core Windows Server roles and services. * Proven experience designing and governing identity, access, and least-privilege controls in a Windows-centric environment. * Strong, hands-on experience administering Microsoft 365 / Office 365 (Exchange Online, Teams, SharePoint, security). * Strong, hands-on experience administering VMware vSphere/ESXi and vCenter. * Experience leading projects, migrations, and disaster recovery planning for core infrastructure. * Demonstrated ability to mentor others and set technical standards and best practices. * Excellent troubleshooting, communication, and stakeholder-management skills with a security-focused mindset., * Bachelor's degree in Information Technology, Computer Science, or a related field (or equivalent experience). * Senior-level certifications such as Microsoft Certified: Windows Server Hybrid Administrator Associate, Identity and Access Administrator Associate (SC-300), or Microsoft 365 Administrator Expert. * Additional certifications such as VMware VCP-DCV or Azure Solutions Architect / Administrator (AZ-104). * Advanced scripting and automation with PowerShell and Microsoft Graph; familiarity with infrastructure-as-code. * Experience with hybrid identity (Entra Connect), Intune / endpoint management, Zero Trust, and security/compliance frameworks. * Solid networking fundamentals (VLANs, firewalls, VPN, load balancing). ## Description We are seeking an experienced Senior Systems Administrator to manage and maintain our core enterprise infrastructure. The Senior System Administrator is the organization's technical lead for Windows Server and Active Directory infrastructure, with strong supporting ownership of Microsoft 365 (Office 365) and VMware virtualization. This is a senior individual-contributor role that combines deep hands-on administration with architecture, standards-setting, and mentorship. The Senior System Administrator designs and operates a secure, resilient, and well-governed environment - leading complex projects and migrations, defining operational best practices, and serving as the highest level of escalation for infrastructure and identity. The ideal candidate is a seasoned, security-minded engineer who can both go deep technically and raise the capability of the wider team., Active Directory & Windows Server (Primary Focus) * Own the architecture, health, and roadmap of Active Directory - domains, forests, trusts, sites, OUs, and replication. * Define and govern Group Policy strategy and standards for security, configuration, and standardization across the estate. * Lead design and administration of core Windows Server roles and services, including DNS, DHCP, file/print, and PKI (AD CS). * Set build, patching, and hardening standards for Windows Server; own server lifecycle and capacity planning. * Establish identity and access-governance practices for user, group, and service accounts (least privilege, tiering). * Maintain and troubleshoot domain controllers, FSMO roles, replication, and authentication (Kerberos/NTLM) at an expert level. * Design and validate backup, restore, and disaster recovery strategy for Active Directory and server workloads. Identity, Security & Hybrid Connectivity * Own hybrid identity strategy and synchronization between on-premises Active Directory and Microsoft Entra ID (Entra Connect). * Define and enforce strong authentication standards, including multi-factor authentication (MFA) and conditional access. * Establish and maintain server and endpoint security baselines, patching cadence, and hardening standards. * Lead support for audits, access reviews, logging, and compliance requirements (e.g., SOC 2, ISO 27001, HIPAA as applicable). * Drive detection of and response to identity- and infrastructure-related security events; lead root-cause analysis. Microsoft 365 / Office 365 Administration * Provide senior-level administration of the Microsoft 365 tenant, including Exchange Online, SharePoint Online, OneDrive, and Microsoft Teams. * Govern licensing, tenant configuration, and administrative role assignments. * Design and maintain Microsoft 365 security and compliance controls (DLP, retention, email protection / Defender for Office 365). * Lead tenant migrations and the adoption of new Microsoft 365 services; resolve complex mail flow and service issues. Virtualization & VMware * Own administration and design of VMware vSphere/ESXi and vCenter, including HA, DRS, and resource strategy. * Lead VM provisioning standards, host upgrades, patching, and capacity planning for performance and availability. * Manage storage and networking within the virtual environment (datastores, vSwitches, VLANs, vMotion). * Lead troubleshooting and remediation of performance and availability issues across the virtualization stack. Leadership, Projects & Collaboration * Serve as the highest level of escalation for complex infrastructure, identity, and platform issues. * Mentor and provide technical leadership to junior administrators and help desk staff; review work and share knowledge. * Lead infrastructure projects, migrations, and upgrades from planning through implementation and handover. * Define automation strategy and build tooling using PowerShell (and Microsoft Graph) to improve reliability and efficiency. * Author and maintain architecture documentation, runbooks, standards, and configuration records. * Partner with security, networking, and application teams; contribute to the infrastructure roadmap and technology decisions. * Participate in and lead an on-call rotation for critical systems as required. ## Related Videos - [WebAssembly: The Next Frontier of Cloud Computing](https://www.wearedevelopers.com/videos/972-webassembly-the-next-frontier-of-cloud-computing) - [Technical Documentation - How Can I Write Them Better and Why Should I Care?](https://www.wearedevelopers.com/videos/681-technical-documentation-how-can-i-write-them-better-and-why-should-i-care) - [Hacking MSSQL on Cloud. All of them. How I became sysadmin on Azure, AWS, GCP and Alibaba.](https://www.wearedevelopers.com/videos/100339-hacking-mssql-on-cloud-all-of-them-how-i-became-sysadmin-on-azure-aws-gcp-and-alibaba) - [Generating code with Angular schematics](https://www.wearedevelopers.com/videos/129-generating-code-with-angular-schematics) - [What makes Cybersecurity different for critical infrastructure?](https://www.wearedevelopers.com/videos/571-what-makes-cybersecurity-different-for-critical-infrastructure) - [Bridging AI and Nomad: a Go-based MCP Server for Cluster Control](https://www.wearedevelopers.com/videos/2063-bridging-ai-and-nomad-a-go-based-mcp-server-for-cluster-control) ## Related Articles - [What Are The Top Skills Required For Azure Developers?](https://www.wearedevelopers.com/magazine/77-what-are-the-top-skills-required-for-azure-developers) - [What’s the Difference between a Junior, Mid, and Senior Developer?](https://www.wearedevelopers.com/magazine/238-what-s-the-difference-between-a-junior-mid-and-senior-developer) - [Highest Paying Tech Companies for Developers](https://www.wearedevelopers.com/magazine/220-highest-paying-tech-companies-for-developers) - [Best Paying Jobs in Technology](https://www.wearedevelopers.com/magazine/256-best-paying-jobs-in-technology) - [The Best Job Search Websites of 2025](https://www.wearedevelopers.com/magazine/368-the-best-job-search-websites-of-2025) - [Top Must-Visit Developer Conferences in the US in 2026](https://www.wearedevelopers.com/magazine/679-top-must-visit-developer-conferences-in-the-us-in-2026)