L3 Network & Security Operations Engineer

About the role

Marsh is looking for a senior L3 Network & Security Operations Engineer to join its Network and Security Operations team in Cluj-Napoca. This hybrid position requires at least three days per week on‑site and focuses on troubleshooting, remediation and implementation of modern load‑balancing and WAN solutions.

Key responsibilities

• Provide L3 escalation support for major incidents, leading technical triage, restoration and stakeholder communication.
• Operate, troubleshoot and implement load‑balancing services, primarily F5 Distributed Cloud (XC) and AWS Elastic Load Balancing (ALB/NLB).
• Manage TLS/SSL enablement across load balancers, firewalls and WAFs, including certificate lifecycle tasks.
• Support SD‑WAN, WAN and branch connectivity, handling routing, carrier issues and LAN/WLAN environments.
• Deliver network changes following ITIL‑aligned governance, including planning, risk assessment and rollback readiness.

Required profile

• Proven L3 network operations experience in a NOC/operations environment.
• Strong troubleshooting skills across L2‑L7 protocols (TCP/TLS, HTTP/HTTPS).
• Hands‑on experience with cloud/distributed load balancing (F5 Distributed Cloud and/or AWS ALB/NLB).
• Solid Cisco multilayer switching knowledge (VLANs, SVIs, routing, HA).
• Experience with WAN/branch connectivity and carrier coordination.

Required skills

• F5 Distributed Cloud, AWS ALB/NLB, legacy F5 BIG‑IP.
• Cisco multilayer switching, VLAN, SVI, routing.
• SD‑WAN technologies (Prisma SD‑WAN, CloudGenix, Aviatrix, Aruba Central, Juniper Mist).
• TLS/SSL certificate management.
• PowerShell and/or Python scripting for automation.
• ITIL change, incident and problem management processes.

What we offer

• Professional development opportunities and supportive leadership.
• Inclusive culture with flexible benefits up to 20% of annual salary.
• 30+ days of paid time off, performance bonus scheme and charitable initiatives.
• Core benefits: pension, life and medical insurance, meal vouchers, travel insurance.