Sistem administrator

About the role

CarPen Rebuild is looking for a proactive System Administrator to join its cybersecurity and IT infrastructure team in Zagreb. You will work on internal and client environments, helping to design, maintain and improve servers, networks and cloud services.

Key responsibilities

• Administer and monitor servers, virtualisation platforms and user workstations.
• Manage Windows Server environments, including Active Directory, DNS, DHCP, Group Policy and user permissions.
• Configure and support Microsoft 365 services, Exchange Online, Teams, SharePoint and OneDrive.
• Maintain network infrastructure – firewalls, VPNs, VLANs and wireless access points.
• Apply security measures, monitor alerts, remediate vulnerabilities and assist in incident response.
• Operate backup systems, verify backups and perform data restoration tests.
• Participate in the development and upkeep of the company’s private cloud infrastructure.
• Mentor junior colleagues and share best practices.
• Provide remote support to clients and keep technical documentation up‑to‑date.

Required profile

• Hands‑on experience in system administration and independent problem solving.
• Strong knowledge of networking concepts (TCP/IP, DNS, DHCP, routing, VLAN, VPN, firewalls).
• Proficiency with Windows Server, Active Directory and Group Policy.
• Experience administering Microsoft 365, Exchange Online and related services.
• Familiarity with security tools (antivirus, EDR, MFA, access management).
• Experience with backup solutions and disaster‑recovery processes.
• Knowledge of at least one virtualization platform (Hyper‑V, VMware or Proxmox).
• Understanding of cloud resource management and hybrid connectivity.
• Good English reading skills and clear communication.

Required skills

• Windows Server
• Active Directory
• Group Policy
• DNS
• DHCP
• Microsoft 365
• Exchange Online
• Teams
• SharePoint
• OneDrive
• Microsoft Entra ID
• TCP/IP
• VLAN
• VPN
• Firewall configuration
• EDR solutions
• MFA
• Backup and recovery tools
• Hyper‑V
• VMware
• Proxmox
• Cloud infrastructure management