Senior Systems Administrator (4 Days Onsite / 1 Remote)

Location: Long Island, NY (Uniondale area)

Employment Type: Full-Time · In-House IT (Not MSP)

Salary - 100k/yr-130k/yr

We are seeking a Senior Systems Administrator to support and enhance our internal IT infrastructure. This is a hands-on technical role managing Windows Server, Active Directory, VMware, Microsoft 365, and core network systems in a professional services environment. The ideal candidate is a mid-senior level IT professional who enjoys ownership, stability, and working directly with IT leadership on system improvements and modernization initiatives.

Key Responsibilities

• Administer and maintain Windows Server, Active Directory, DNS, DHCP, and Group Policy

• Manage VMware vSphere/vCenter environments (resource tuning, HA/DRS, provisioning)

• Support Microsoft 365 (Exchange Online, Teams, security/compliance settings)

• Assist with network administration, including VLANs, VPNs, routing/switching

• Support firewall configuration and remote access (SonicWall experience a plus)

• Serve as Tier 3 escalation for complex systems and infrastructure issues

• Participate in infrastructure upgrades, cloud integrations, and security hardening efforts

• Maintain system documentation, runbooks, and standard operating procedures

Qualifications

• 5–10 years of hands-on experience in Systems Administration or Systems Engineering

• Strong experience with Windows Server & Active Directory

• Proficiency with VMware vSphere/vCenter in production environments

• Experience managing Microsoft 365 in a hybrid AD environment

• Strong grasp of networking fundamentals (TCP/IP, VLANs, VPNs)

• Experience with PowerShell scripting/automation

• Clear communication skills and strong documentation habits

Preferred (Not Required)

• SonicWall, Cisco, or Meraki networking experience

• Previous experience in professional services IT (legal, finance, consulting, etc.)

• Relevant certifications (Microsoft, VMware, CompTIA, etc.)

Work Arrangement

4 days onsite / 1 remote weekly.

This role involves interaction with end users and direct support of firm systems, so full remote or fully hybrid schedules are not available.

We are hiring directly and are not working with recruiters or staffing agencies.

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