L3 Network Security Engineer (Managed Firewall | Network Infrastructure)

About the Role:

Saint Fox is looking for an experienced L3 Network Security Engineer to own the design, deployment, and day-to-day management of enterprise network security infrastructure for our clients. This is a senior hands-on role. You will work across Cisco and Palo Alto environments, drive incident escalations to closure, mentor junior engineers, and contribute to architecture decisions. You will sit within the Managed Firewall and Secure Access practice, working closely with Security Analysts and Principal Engineers to keep client environments stable, documented, and audit-ready.

• Design, deploy, and manage Cisco ASA and Firepower Threat Defense (FTD) firewalls in enterprise and multi-site environments.

• Operate and tune Palo Alto Networks next-generation firewalls including policy management, App-ID, User-ID, and threat prevention profiles.

• Manage Palo Alto Panorama for centralised policy and device management across multiple firewalls.

• Perform rule-base reviews, clean-up, and optimisation on a scheduled basis to reduce attack surface and policy drift.

• Respond to and resolve L3 firewall incidents and escalations within agreed SLA windows.

• Configure and manage Cisco Catalyst and Nexus switching platforms including VLANs, STP, VPC, and QoS.

• Administer Cisco Wireless infrastructure including WLC (Wireless LAN Controllers) and Cisco Access Points across campus and branch environments.

• Troubleshoot complex Layer 2 and Layer 3 network issues from physical through to application layer.

• Maintain and enforce network segmentation policies aligned to Zero Trust principles. Routing and Connectivity

• Configure and manage dynamic routing protocols including OSPF, BGP, and EIGRP.

• Manage site-to-site and remote-access VPN including Cisco AnyConnect and Palo Alto Global Protect.

• Support SD-WAN and SASE integration efforts where applicable

• Own change management for network security changes including planning, testing, and rollback procedures.

• Maintain accurate and current network diagrams, run books, and configuration documentation.

• Participate in vulnerability and patch management cycles for network devices.

• Support internal and external audits by providing evidence and configuration reviews.

• Provide mentoring and technical guidance to L1 and L2 engineers

• 8 to 15 years of hands-on experience in network security engineering.

• At least 4 years working at L3 or equivalent senior engineer level.

• Demonstrated production experience with Cisco ASA and/or FTD firewalls.

• Demonstrated production experience with Palo Alto Networks NGFW and Panorama.

• Solid experience with Cisco Catalyst and Nexus switching in enterprise environments.

• Working experience with Cisco WLC and enterprise access point management.

• Cisco Firewall: ACLs, NAT, VPN, HA, and Firepower management centre.

• Cisco Switching: VLAN, STP, RSTP, VPC/vPC, port-channel, QoS, and SPAN.

• Cisco Wireless: WLC management, AP provisioning, SSID design, RF planning basics, and client troubleshooting.

• Palo Alto: Security policies, NAT, decryption, URL filtering, Wildfire, Panorama, and HA configuration.

• Routing: OSPF, BGP, EIGRP, PBR, and route redistribution.

• VPN: IPsec, SSL-VPN, GlobalProtect, and AnyConnect.

• Packet analysis using Wireshark or equivalent.

• Working knowledge of NAC, 802.1X, and RADIUS.

• Required: CCNP Security or CCNP Enterprise (current and valid).

• Preferred: Palo Alto PCNSE (or working towards it).

• Preferred: Cisco CCIE Security or equivalent advanced certification.

• Clear communicator. You can explain a complex network problem to a non-technical stakeholder without burying them in acronyms.

• Methodical under pressure. You follow process during incidents and document what happened after ward.

• Self-directed. You manage your workload, flag blockers early, and do not wait to be chased.

• Collaborative. You work well with security analysts, project managers, and client technical teams

• Opportunity to work onsite at a leading customer location, enabling direct engagement with innovative projects.

• A collaborative and dynamic working environment focused on continuous learning and professional growth.

• Exposure to advanced technologies and ongoing training opportunities.

• Clear career progression pathways supported by experienced leadership.

• An opportunity to work in a rapidly growing company with potential for personal and professional growth.

• Opportunity to work in a rapidly growing company with potential for personal and professional growth.

• A collaborative and inclusive culture that values each employee’s contribution towards our goals.

• Competitive compensation package including attractive bonus structures and benefits

How to Apply: Interested candidates should submit a detailed resume and a cover letter outlining their qualifications and experience relevant to the role applied for. Applications should be sent via our careers portal or to [email protected]