Senior Systems Administrator – Sydney (6‑month contract)

About the role

We are seeking a Senior Systems Administrator to join a leading enterprise client in Sydney on a 6‑month contract, with the possibility of extension. The role focuses on designing, building and hardening critical Windows and Linux server infrastructure, including Active Directory environments, to support large‑scale production deployments.

Key responsibilities

• Design, build and configure Active Directory servers to enterprise SOE standards.
• Promote and integrate AD servers into the corporate domain.
• Implement server hardening using Group Policy and off‑domain security controls.
• Perform system patching, firmware updates and ongoing maintenance.
• Build and configure Windows and Linux servers.
• Monitor system performance, troubleshoot issues and optimise environments.
• Support testing, validation, Operational Readiness Evaluation (ORE) and production go‑live activities.
• Follow established Standard Operating Procedures for server builds.
• Assist with virtual server migrations as required.

Required profile

• Extensive experience administering Windows and Linux server environments.
• Strong expertise in Active Directory, DNS and domain services.
• Hands‑on experience with VMware virtualization.
• Experience building systems to Standard Operating Environment (SOE) requirements.
• Deep knowledge of system hardening, Group Policy and security best practices.
• Proven track record with patch management, firmware updates and infrastructure maintenance.
• Strong troubleshooting, monitoring and performance‑tuning skills.
• Experience supporting production deployments and go‑live activities.
• Experience with virtual server migrations is highly regarded.

Required skills

• Windows Server
• Linux
• Active Directory
• DNS
• VMware
• Group Policy (GPO)
• Patch Management
• Firmware Updates
• System Hardening
• Performance Monitoring
• Virtual Server Migration