System Administrator – Windows, Linux, Virtualization

Welvaart

System Administrator managing VMware and Microsoft 365 environments for a growing technology startup. Involves virtual infrastructure management and support for internal teams.

Posted 4/13/2026full-timeLisbon • 🇵🇹 PortugalMid-LevelSeniorWebsite

Tech Stack

Tools & technologies

CloudLinuxVMware

About the role

Key responsibilities & impact

Hardware sizing for the virtualization infrastructure
Installation and configuration of VMware/Omnissa environments
Creation and configuration of base images for virtual PCs
Definition and implementation of virtual PC pools
Administration and optimization of hardware resources associated with virtualization
Capacity management and monitoring of virtual PC pools
Performance measurement and analysis to ensure stability and efficiency
Planning and implementation of solution upgrades and improvements
Updating and maintenance of virtual PC base images
Direct support to users and internal teams
Diagnosis and resolution of incidents related to the platform
Installation, configuration and management of Active Directory and Exchange environments in hybrid infrastructures (Cloud + On-premises)
Administration and support of Office 365 services, including Teams and OneDrive
Management, monitoring and continuous improvement of corporate Microsoft environments
Creation of Windows base images (OS + drivers + corporate software) prepared for deployment to new devices via SCCM/Intune
Testing and validation of Windows upgrade processes using automated pipelines in SCCM/Intune
Planning and implementation of security update policies on corporate devices
Creation, management and deployment of software installation and update packages
Ensuring up-to-date inventory and compliance of software installed on the organization's devices

Requirements

What you’ll need

Proven experience with VMware/Omnissa environments
Strong knowledge of Microsoft 365, Active Directory and Exchange management
Hands-on experience with SCCM and/or Intune
Ability to diagnose and resolve complex problems
Autonomy, attention to detail and good communication with users and technical teams
Knowledge and experience with Omnissa (formerly Horizon), including virtual desktop management and troubleshooting
Strong technical aptitude; profiles with advanced Linux skills are highly valued
Ability to communicate effectively with users and show empathy in daily support
Technical English sufficient for contacts with Microsoft and VMware support
Availability to participate in monthly on-call rotations
4–5 years of professional experience in systems administration or similar roles
Previous experience in large-scale environments, especially related to virtual PCs and proportionality models

Benefits

Comp & perks

Fair and equitable compensation structure
Training and certification
Career path management

ATS Keywords

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Applicant Tracking System Keywords

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Hard Skills & Tools

VMwareOmnissaActive DirectoryExchangeOffice 365SCCMIntuneWindows base imagesvirtual desktop managementLinux

Soft Skills

problem diagnosiscommunicationattention to detailautonomyempathy