Senior Systems & Network Administrator - Cloud & Security Ops

Island Capital Group; Irving, Northern (TX, KY); Hybrid; USD 90,000 - 150,000; Full time

Job summary

Island Capital Group is seeking a Senior Systems Administrator to manage enterprise IT infrastructure across security, cloud, and network domains. The role combines hands-on administration with incident triage, documentation, procurement coordination, and maintenance execution.

You will work on Microsoft Sentinel/Defender monitoring, Azure infrastructure, Cisco devices, and DNS/certificate workflows, ensuring operational resilience and security posture.

Qualifications

• Experience across Windows Server, AD, DNS, DHCP, and Group Policy.
• Expertise in security operations, incident response, and documentation.
• Familiarity with monitoring and patching workflows across enterprise infrastructure.

Responsibilities

• Investigate and triage security alerts using Sentinel and Defender; document responses.
• Administer Azure infrastructure, firewall rules, and VPN-related changes.
• Coordinate Cisco routing, licensing, and renewal activities with vendors.
• Manage Constellix DNS records and DigiCert DCV revalidation workflows.
• Monitor network, certificate, and device health; respond to incidents and outages.
• Create KBs and runbooks for repeatable IT tasks and security controls.

Skills

Security operations

Networking

Cloud infrastructure

Incident triage

Monitoring

Documentation

Procurement coordination

DNS/Certificate mgmt

Tools

Windows Server AD

VMware

Cisco IOS

Veeam

Constellix DNS

DigiCert DCV

GoAnywhere

Azure

Job description

Island Capital Group is seeking a Senior Systems Administrator to manage enterprise IT infrastructure across security, cloud, and network domains. The role combines hands-on administration with incident triage, documentation, procurement coordination, and maintenance execution.

You will work on Microsoft Sentinel/Defender monitoring, Azure infrastructure, Cisco devices, and DNS/certificate workflows, ensuring operational resilience and security posture.