Systems Administrator (Linux & Windows)

Systems Administrator (Linux & Windows)Location: Greenwich, CTEmployment Type: Full‑time, Direct HireWork Model: 5 days/week onsiteAdditional Travel: 2–3 times per month to the White Plains, NY datacenterAbout the RoleWe’re seeking a highly skilled Systems Administrator to support and evolve a diverse, mission‑critical IT infrastructure spanning on‑premise and offsite datacenters. In this role, you’ll manage servers, networking, VMware environments, and physical hardware while collaborating closely with the CTO, Engineering, Data, and Systems teams.You’ll help define technical requirements, build reliable internal systems, strengthen cybersecurity posture, and ensure smooth day‑to‑day operations. This position also includes triaging, prioritizing, and routing support tickets to maintain efficient issue resolution. We’re looking for someone who brings strong technical depth, proactive thinking, and a vision for infrastructure modernization.ResponsibilitiesAdminister and maintain Linux and Windows server environmentsManage VMware vSphere infrastructureSupport Active Directory, Microsoft 365, Teams, and MFA solutionsOversee networking components including TCP/IP, DNS, DHCP, VLANs, and firewallsMonitor and secure email flow, including spam/malware filtering and DLPAutomate tasks using PowerShell, Python, or BashPerform hands‑on datacenter work: racking, cabling, diagnostics, and hardware replacementCollaborate with cross‑functional teams to define system requirements and implement improvementsPrioritize and route support tickets to ensure timely resolutionContribute to IT and cybersecurity policy developmentRequired QualificationsExpertise with Windows Server, Active Directory, Microsoft 365, Teams, and MFAStrong enterprise Linux administration experienceVMware vSphere proficiencySolid understanding of email security, filtering, and DLPStrong networking knowledge (TCP/IP, DNS, DHCP, VLANs) and firewall managementScripting experience (PowerShell, Python, Bash)Hands‑on experience with physical server hardware and datacenter operationsExcellent troubleshooting and communication skillsProficiency in server installation, configuration, and maintenancePreferred QualificationsDegree in Information Technology or related field (or equivalent experience)5+ years managing enterprise‑level infrastructureExperience with AWS or AzureExperience with Ansible or similar configuration‑management tools