Senior System Administrator

About the role

Cornerstone Development is looking for a Senior System Administrator to lead the management and maintenance of its IT infrastructure. The role ensures system stability, security and high performance across all business operations, while providing technical support to internal users.

Key responsibilities

• Administer Windows servers and Active Directory.
• Manage Microsoft 365 services.
• Oversee virtualization (VMware) and backup (Veeam) solutions.
• Configure and maintain firewalls (Sophos, FortiGate) and network security.
• Support Linux and VoIP systems.
• Implement and monitor cybersecurity measures.
• Participate in IT projects and cross‑functional collaboration.
• Troubleshoot and resolve infrastructure incidents.

Required profile

• Bachelor’s degree in Computer Science, IT or a related field.
• Minimum 3 years of system administration or IT infrastructure experience.
• Proven experience with Microsoft 365 administration.
• Hands‑on experience with virtualization, backup and firewall technologies.
• Familiarity with cloud services such as Microsoft Azure.
• Relevant certifications (MCSA, MCSE, CCNA, CompTIA Security+, VMware VCP) are a plus.
• Ability to work independently and within a team.
• Strong analytical and problem‑solving skills.

Required skills

• Windows Server Administration.
• Active Directory & Group Policy.
• Network configuration & troubleshooting.
• Sophos & FortiGate firewall management.
• Microsoft 365 administration.
• VMware virtualization.
• Veeam backup & disaster recovery.
• Linux system administration.
• VoIP system support.
• Microsoft Azure fundamentals.
• Security best practices.