Senior Systems Administrator

Description

We are seeking an accomplished Senior Systems Administrator to serve as a senior technical resource within our IT organization. This role owns the design, administration, and continuous improvement of our enterprise IT infrastructure including on-premises systems, cloud environments, identity platforms, cybersecurity operations, and core network services. The ideal candidate brings deep technical breadth, a strong security mindset, leadership through influence, and the maturity to operate independently on complex, high-impact initiatives while mentoring the broader IT team.

Infrastructure Leadership:

• Serve as the senior technical authority for all enterprise infrastructure including Windows Server, Linux, virtualization, storage, and backup systems

• Design, implement, and maintain scalable, highly available infrastructure architecture across on-premises and cloud environments

• Lead infrastructure projects from architecture through deployment: hardware refreshes, data center operations, cloud migrations, and platform upgrades

• Establish and enforce infrastructure standards, naming conventions, and configuration baselines across all managed systems

• Own capacity planning, lifecycle management, and technology roadmap input for infrastructure platforms

Cloud & Identity:

• Serve as the senior administrator for Microsoft Azure/Entra ID including hybrid identity, SSO, MFA, Conditional Access, and Privileged Identity Management (PIM)

• Manage and optimize the Microsoft 365 tenant at an advanced administrative level: Exchange Online, SharePoint, Teams, Intune, and Microsoft Defender

• Lead cloud strategy execution including IaaS/PaaS adoption, cloud cost governance, and architecture decision-making

• Design and maintain network security architecture: firewall rules, VLANs, SD-WAN, VPN, and Zero Trust network access principles

Security & Compliance:

• Work with IT leadership on enterprise cybersecurity operations programs including EDR, SIEM, vulnerability management, and incident response

• Lead patch management strategy and execution across all endpoints, servers, and network devices

• Work with IT leadership conducting regular security assessments and drive remediation of identified vulnerabilities

• Develop and maintain security policies and procedures aligned with NIST CSF or equivalent frameworks

• Support internal audits, external assessments, and regulatory inquiries from an IT infrastructure perspective

Team Leadership & Mentorship:

• Provide technical mentorship and day-to-day guidance to the IT Support Specialist team

• Conduct architecture reviews for infrastructure changes proposed by junior staff

• Develop and maintain comprehensive technical documentation including architecture diagrams, runbooks, SOPs, and change logs

• Lead root cause analysis (RCA) for major incidents and drive post-incident reviews and remediation

• Serve as the primary IT operational decision-maker in the IT Director’s absence

Automation & Continuous Improvement:

• Develop and maintain PowerShell and scripting solutions to automate repetitive administrative tasks, reporting, and compliance checks

• Identify and drive opportunities to improve IT operational efficiency and strengthen security posture

• Evaluate and recommend emerging technologies to IT leadership with well-reasoned business cases

• Manage strategic vendor relationships for infrastructure, cloud, and security services

Requirements

Required Qualifications:

• 6+ years of progressive IT infrastructure and systems administration experience with demonstrated senior-level ownership

• Expert-level proficiency in Windows Server (2016/2019/2022): Active Directory, Group Policy, DNS, DHCP, DFS, and certificate services

• Advanced Microsoft Azure administration: Entra ID, Intune, Defender, or equivalent cloud security platform

• Deep expertise in VMware vSphere (vCenter, ESXi, vSAN) or Microsoft Hyper-V at scale

• Strong networking skills: routing, switching, VLANs, BGP/OSPF fundamentals, firewall policy management, VPN, and SD-WAN

• Proven PowerShell scripting and automation capabilities

• Demonstrated experience leading infrastructure projects and mentoring junior IT staff

• Strong written communication skills and ability to produce clear technical documentation

Preferred Qualifications:

• Microsoft Certified: Azure Administrator Associate (AZ-104) or Azure Solutions Architect Expert (AZ-305)

• VMware Certified Professional (VCP-DCV) or equivalent

• CompTIA Security+ or equivalent security certification