Senior Systems Administrator – Infrastructure Maintenance

About the role

We are seeking an experienced Senior Systems Administrator to join a large enterprise technology team in Sydney. In this hands‑on operational role you will ensure the stability, security and performance of mission‑critical Windows and Linux server platforms.

Key responsibilities

• Administer and support enterprise Windows and Linux server environments.
• Perform regular patching, upgrades and vulnerability remediation.
• Monitor platform health, performance, availability and capacity.
• Respond to incidents, investigate root causes and contribute to problem management.
• Support infrastructure implementations, upgrades and continuous‑improvement initiatives.
• Work across virtualised environments such as VMware vSphere and Hyper‑V.
• Maintain Active Directory, DNS, NTP and other core infrastructure services.
• Contribute to security, compliance and governance activities.
• Develop and improve operational documentation, standards and support procedures.

Required profile

• 5+ years of systems administration or infrastructure support experience in an enterprise setting.
• Strong background administering Windows Server and/or Linux.
• Experience with VMware vSphere, Hyper‑V or similar virtualization technologies.
• Solid knowledge of Active Directory, DNS, NTP and core infrastructure services.
• Proven experience with enterprise patch management and vulnerability remediation.
• Exposure to backup and recovery platforms.
• Good understanding of networking, storage and infrastructure security concepts.
• Excellent communication skills and ability to work across multiple technology teams.

Required skills

• Windows Server administration
• Linux system administration
• VMware vSphere
• Microsoft Hyper‑V
• Active Directory
• DNS
• NTP
• Patch management
• Vulnerability remediation
• Backup and recovery platforms
• Networking fundamentals
• Storage concepts
• Infrastructure security
• Technical documentation

What we offer

• Long‑term contract with exposure to enterprise‑scale infrastructure.
• Work with modern server and virtualization platforms.
• Collaborative infrastructure team focused on operational excellence.
• Opportunity to contribute to platform reliability, security and continuous improvement.
• Rotating support roster covering Wednesday through Sunday.