Senior Systems Administrator

Senior Systems Administrator

About the role

To support the next phase of the PMB Defence journey, an opportunity now exists for an experienced Senior Systems Administrator to be part of our team. Reporting to the Senior IT and Cyber Security Manager, this newly created role will provide key technical support, lead system enhancements and contribute to ICT projects that strengthen cyber resilience and operational capability.

This is an excellent opportunity for a qualified professional looking to enter or continue their career in the defence sector with an Adelaide based business. Key responsibilities will include:

  • Administer and optimise Microsoft 365 and Azure environments, including hybrid identity, access control, endpoint configuration, and system performance monitoring.
  • Implement security baselines and policies aligned with Essential 8 and ISM requirements to maintain secure, reliable cloud and network operations.
  • Provide Tier 3 technical support, mentor IT support staff, and proactively monitor and resolve incidents using Microsoft Defender, Sentinel, and centralised monitoring tools.
  • Maintain reliable backup and recovery processes for Microsoft 365 and Azure workloads while ensuring accurate asset, licensing, and configuration records.
  • Maintain strong cybersecurity controls across systems, devices, and user identities, responding to security alerts, vulnerabilities, and audit findings.
  • Support compliance with ISM, PSPF, DISP, and Cyber Essentials+ (UK) standards, and assist with disaster recovery and incident response testing.
  • Lead infrastructure and security projects focused on cloud optimisation, system modernisation, and automation, identifying and implementing improvements through scripting and automation tools.
  • Collaborate with stakeholders and vendors to deliver technology solutions aligned with business and Defence compliance requirements, escalating complex issues when needed.
  • Maintain accurate system configurations, policies, and recovery documentation while supporting ICT governance, audit readiness, and compliance with internal and Defence standards.
  • Contribute to ICT roadmaps and drive ongoing improvements to strategic IT services and practices.

The successful candidate will possess the following qualifications, skills and experience:

  • Tertiary degree qualifications (Bachelor of IT Systems Administration or similar) or equivalent demonstrated experience in a complex senior systems administration role
  • Vendor Certifications (E.g. Microsoft MS-102, AZ-104, SC-300)
  • Strong Microsoft 365 administration (Exchange Online, SharePoint, Teams, Intune, Azure AD).
  • PowerShell scripting and cloud/identity automation.
  • Experience with monitoring, logging, and backup solutions for cloud services.
  • Knowledge of ISM, Essential 8, and zero trust security frameworks.
  • Network fundamentals (DNS, DHCP, VPNs, firewalls).
  • Experience in maintaining infrastructure systems and platforms within the framework governed by PSPF, ISM, CE+ and NIST
  • Customer focused mindset with a commitment to improving user experience and service quality
  • Collaborative and team oriented, with the ability to build effective relationships across the organisation
  • Excellent communication skills, with the ability to explain complex technical concepts to nontechnical stakeholders

Prerequisites

  • Be eligible to successfully obtain and maintain a NV1 Australian Defence Security Clearance (must be an Australian Citizen)
  • Hold a current driver’s licence.
  • Ability to obtain a current police clearance.
  • Ability to pass a pre-employment medical and Drug & Alcohol screen.
  • Ability to travel occasionally interstate and overseas for work and training purposes.
  • Undertake six monthly/quarterly lead in blood testing

Ready to Apply?

If you are ready to take the next step in your career, we’d love to hear from you.

Click here to apply.

For confidential enquiries and a job and person description, please contact hr@pmbdefence.com.au.

PMB Defence are a 2026 Circle Back Initiative Employer and commit to respond to every applicant.