Sr System Engineer (Wintel)

Unisys; Sydney; On-site; AUD 90,000 - 130,000; Full time

Job summary

Unisys in Sydney, Australia, is seeking a skilled identity and cloud infrastructure specialist to support and maintain enterprise Windows Server, PKI, and cloud services across on‑premises and cloud environments.

You will administer Active Directory, Entra ID/Entra Connect, Keyfactor Command, and collaborate on Azure Virtual Desktop, Nerdio, and AWS-integrated solutions to ensure availability, security, and compliance through incident management and automation.

Qualifications

• Proven experience administering Windows Server environments.
• Strong PKI and certificate management, preferably Keyfactor Command.
• Hands-on Active Directory and Domain Controllers administration.
• Experience with Entra Connect and Entra ID.

Responsibilities

• Operate and maintain Windows Server environments including patching and hardening.
• Manage PKI and certificate lifecycle; administer KeyFactor Command.
• Administer Active Directory and Domain Controllers; manage GPOs and replication.
• Support cloud identity and connectivity with Entra Connect/Entra ID; integrate with on-prem systems.
• Automate tasks via scripting; document runbooks and health checks.

Skills

Incident management

Automation scripting

Strong communication

Cross-functional teamwork

Troubleshooting

Security clearance NV1

Tools

Windows Server

Active Directory

Entra Connect

Entra ID

Keyfactor Command

Azure Virtual Desktop

Nerdio

AWS-integrated solutions

Job description

Support and maintain enterprise identity, PKI, and cloud infrastructure services across on-premises and cloud environments. Responsible for the administration of Windows Server, Active Directory, Microsoft Entra ID, Entra Connect, and Keyfactor Command, while supporting Azure Virtual Desktop (AVD), Nerdio, and AWS-integrated solutions. The role focuses on ensuring system availability, security, and compliance through incident management, certificate lifecycle administration, automation, monitoring, troubleshooting, and continuous service improvement.

Key responsibilities

• Operate and maintain Windows Server environments - including patching, hardening, and troubleshooting
• Manage PKI and certificate lifecycle - design, issue, renew, and revoke certificates; administer KeyFactor Command
• Administer Active Directory and Domain Controllers - including GPOs, replication, and AD health
• Support cloud identity and connectivity - Entra Connect, Entra ID, and integration with on-prem systems
• Manage AWS Connect - integrations and related cloud services
• Deploy and support Azure Virtual Desktop - environments and user profiles
• Administer Nerdio - or AVD provisioning and management
• Participate in incident response, root cause analysis, and postmortems
• Automate operational tasks using scripting where appropriate
• Document runbooks, run regular health checks, and provide knowledge transfer

About you

• Proven experience with Windows Server administration
• Strong knowledge of PKI and certificate management - experience with KeyFactor Command preferred
• Hands-on Active Directory and Domain Controller experience
• Experience with Entra Connect and Entra ID - configuration and troubleshooting
• Familiarity with Azure AVD and Nerdio - for desktop virtualization
• Experience integrating on-prem identity with cloud services
• Scripting skills - for automation and operational tasks
• Solid troubleshooting and incident management skills
• Good communication skills and ability to work within cross-functional teams
• NV1 security clearance must have for this role

Nice to have

• VMware - administration experience.
• CyberArk Machine Identity or other machine identity management experience.
• Experience with AWS services.
• Certifications such as Microsoft Certified - Azure Administrator, Microsoft Certified: Identity and Access Administrator, or relevant security certifications.