Senior IT Systems Administrator; On-Site

Senior IT Systems Administrator (On-Site)

Job Category: Administration

Requisition Number: ITBUS
001223

• Posted :
  August 31, 2026
• Full-Time
• On-site

Showing 1 location

Hilton Head Island, SC 29928, USA

Senior IT Systems Administrator

Position Summary

The Senior IT Systems Administrator serves as one of the organization's lead technical experts and subject matter authority for enterprise infrastructure systems. This position is responsible for the architecture, security, administration, maintenance, and continuous improvement of the organization's network, firewall, wireless, server, virtualization, storage, and data center environments. This role is onsite and remote work is not available.

This role functions as one of highest technical escalation points within the IT Systems Administration team, providing leadership, mentoring, and expert guidance to IT technicians and support staff. The Senior IT Systems Administrator is responsible for ensuring the stability, security, availability, and performance of all core infrastructure systems while supporting business operations through proactive planning, problem resolution, and technology modernization initiatives.

The position requires a strong commitment to operational excellence, cybersecurity, disaster recovery preparedness, and maintaining highly available enterprise systems that support mission-critical business functions.

Essential Duties and Responsibilities

Technical Leadership & Mentorship

• Serve as the primary technical authority and escalation point for infrastructure-related issues across the organization.
• Provide technical leadership, mentoring, coaching, and guidance to IT technicians and support personnel.
• Assist team members in troubleshooting complex technical issues and developing effective solutions.
• Lead root cause analysis activities for major incidents, service interruptions, and recurring technical problems.
• Establish and maintain infrastructure standards, best practices, operational procedures, and technical documentation.
• Collaborate with IT leadership to develop and execute infrastructure strategies and technology roadmaps.
• Evaluate emerging technologies and recommend improvements that enhance reliability, security, scalability, and operational efficiency.
• Act as a trusted advisor to IT staff and business leaders regarding infrastructure technologies, architecture, and cybersecurity risks.

Network Infrastructure Management

• Design, implement, maintain, and support enterprise network infrastructure, including switches, routers, firewalls, VPNs, and wireless networking systems.
• Ensure maximum availability, performance, and reliability of all network services.
• Monitor network performance and proactively resolve issues before service disruptions occur.
• Manage network configurations, documentation, capacity planning, and system upgrades.
• Lead troubleshooting efforts related to connectivity, performance, and network security concerns.

Cybersecurity & Compliance

• Maintain and strengthen the security posture of the organization's infrastructure environment.
• Administer firewalls, security appliances, intrusion prevention systems, and network access controls.
• Ensure operating systems, firmware, applications, and infrastructure components remain current with security updates and patches.
• Identify and remediate vulnerabilities through proactive monitoring and vulnerability management practices.
• Participate in incident response efforts and lead infrastructure‑related security investigations.
• Support compliance initiatives and ensure adherence to organizational security policies and industry best practices.
• Administer and maintain VMware virtualization environments, including hosts, clusters, storage, and virtual machines.
• Manage enterprise server infrastructure supporting business‑critical applications and services.
• Ensure data center equipment remains operational, secure, and highly available.
• Monitor server performance, capacity, and utilization to ensure optimal operation.
• Perform system maintenance, upgrades, and lifecycle management activities.
• Coordinate vendor support and maintenance activities related to infrastructure systems.

Storage, Backup & Disaster Recovery

• Manage enterprise storage arrays and related technologies.
• Ensure data backup solutions operate successfully and consistently meet recovery objectives.
• Develop, test, and maintain disaster recovery and business continuity procedures.
• Monitor storage utilization and forecast future capacity requirements.
• Lead recovery…