Senior Network Administrator – Johannesburg

About the role

Our client, a multi‑industry group, is looking for an experienced Senior Network Administrator to join their IT team in City Deep, Johannesburg. You will be responsible for the design, maintenance, security and performance of the organisation’s network infrastructure, ensuring reliable connectivity for both on‑premise and cloud environments.

Key responsibilities

• Manage LAN, WAN, VPN, VLAN, Wi‑Fi and internet connectivity.
• Monitor network performance, troubleshoot complex issues and perform failover testing.
• Configure and maintain routers, switches, firewalls, access points and Mikrotik RouterOS devices.
• Maintain documentation of network configurations and procedures.
• Implement and manage firewalls, access control policies and vulnerability‑patching processes.
• Plan and execute network upgrades, migrations and firmware updates.
• Support server environments, backups, disaster‑recovery and system performance optimisation.
• Assist with group‑wide IT projects and mentor junior staff.

Required profile

• Matriculation (A+) with N+ certification and Microsoft MCITP or equivalent.
• Network Security+ certification or similar.
• Minimum 5 + years of experience in IT administration and enterprise networking.
• Strong analytical, problem‑solving and communication skills.

Required skills

• TCP/IP, DNS, DHCP, VLANs, routing protocols.
• Firewalls, switches, wireless infrastructure.
• Microsoft Active Directory, Microsoft 365.
• Windows Server 2019/2022, Windows 10/11.
• Hyper‑V virtualization.
• Site‑to‑site and client VPNs.
• Mikrotik RouterOS.
• Network monitoring tools.
• VOIP systems.
• Cloud technologies – Azure, Exchange Online.