Systems Administrator

Systems Administrator- 70% Windows 30% Linux Location: Onsite (Old Greenwich, CT) Employment Type: Full-Time Salary: 150K-180K + 20% Bonus We are seeking a hands-on Systems Administrator to manage and evolve a diverse IT infrastructure environment. This role is responsible for maintaining servers, networking, virtualization platforms, and core business systems across both on-premise and cloud environments. You will work closely with engineering, data, and leadership teams to support day-to-day operations, improve system performance, and strengthen security practices. This is a highly collaborative role requiring both technical depth and the ability to support business-critical systems. Key Responsibilities Administer and maintain 80 % Windows Server, Active Directory, and Microsoft 365 environments Support 20% Linux systems within an enterprise infrastructure Manage virtualization platforms, including VMware vSphere Configure and maintain network infrastructure (TCP/IP, DNS, DHCP, VLANs) Monitor and manage firewalls to ensure network security and access control Oversee email systems, including routing, spam filtering, malware protection, and DLP Troubleshoot and resolve technical issues; manage and prioritize support tickets Perform hands-on hardware work including server installation, racking, cabling, and component replacement Develop and maintain automation scripts using PowerShell, Python, or Bash Collaborate with cross-functional teams to support infrastructure needs and improvements Contribute to IT operations and cybersecurity policies and best practices Required Qualifications Strong experience with Microsoft Windows Server, Active Directory, and Microsoft 365 Working knowledge of Linux system administration Experience with VMware vSphere or similar virtualization platforms Solid understanding of networking fundamentals and protocols Experience managing firewalls and network security Familiarity with scripting for automation (PowerShell, Python, or Bash) Hands-on experience with physical server hardware and data center environments Strong problem-solving skills and attention to detail Excellent communication skills with the ability to support non-technical stakeholders Preferred Qualifications Bachelor s degree in Computer Science, Information Technology, or related field (or equivalent experience) 5+ years of experience in systems administration or infrastructure roles Experience with cloud platforms such as AWS or Azure Familiarity with configuration management tools (e.g., Ansible)