About our Client
They are a mission-driven technology organisation delivering secure, scalable data solutions across highly regulated and critical environments. Their work supports complex, high-impact programs spanning government, defence-aligned initiatives, healthcare, and commercial sectors.
As a growing and innovative business, they pride themselves on building high-performing teams that value ownership, curiosity, trust, and technical excellence. This is an opportunity to join an organisation where your work directly contributes to systems that matter.
About the Role
We are seeking a highly experienced Principal System Administrator to lead the design, deployment, and maintenance of secure data management platforms within defence-aligned environments. This is a senior technical leadership role where you’ll take ownership of critical infrastructure, ensuring secure, compliant, and high-performing IT operations.
Reporting directly to the President, you will play a key role in shaping system architecture, driving operational excellence, and supporting secure environments across multiple on-premises sites.
Key Responsibilities
- Architect, deploy, and maintain a resilient Linux server environment
- Manage Active Directory, Group Policy, identity & access management (IAM) and network configurations
- Configure and support firewalls, routers, switches, VLANs, DNS, and IAM integrations
- Lead system lifecycle activities including installation, configuration, testing, and troubleshooting
- Provide end-user support, resolving technical issues and access challenges
- Oversee patch management, compliance, change control, and vulnerability remediation
- Implement system hardening aligned with Essential Eight and conduct regular security audits
- Maintain and optimise production Kubernetes (K8s) clusters, including deployment, scaling, monitoring (Prometheus/Grafana), and troubleshooting
- Collaborate with internal teams and external stakeholders, delivering technical insights and recommendations to leadership
- Provide technical leadership and mentorship to engineering teams
You are a highly skilled systems professional who thrives in secure, complex environments and demonstrates leadership, accountability, and curiosity.
Essential Experience & Skills
- Minimum 10 years’ experience in system administration or IT infrastructure
- Strong expertise in Linux system administration and Active Directory
- Proven experience with networking (CCNA/CCNP or equivalent hands-on experience)
- Proficiency in scripting ( PowerShell, Bash, Python)
- Experience managing Kubernetes environments in production
- Deep understanding of security frameworks and system hardening practices
- Strong analytical and troubleshooting capability
- Demonstrated experience leading or mentoring technical teams
- Relevant tertiary qualification or equivalent practical experience
- Willingness to travel across Australia to customer and partner sites (including secure environments)
- Australian citizenship with an AGSVA NV2 security clearance
Please upload your resume to apply. We will be in touch with further instructions for suitably skilled candidates.
Call Katrina Gabriel on 0489 923 756 or email katrinag@whizdom.com.au for any further information.   
Candidates will need to be willing to undergo pre-employment screening checks which may include, ID and work rights, security clearance verification and any other client requested checks.
