Senior Network Engineer

Trellint; Portsmouth; On-site; GBP 70,000 - 90,000; Full time

Job summary

Trellint is seeking a Senior Network Engineer to lead the design, implementation, and support of enterprise network infrastructure across its UK data centers and offices. You will focus on data center networking, load balancing, and core services to ensure high availability, performance, and security.

You will design and implement network solutions, mentor team members, and work with IT leadership to align infrastructure with business goals.

Qualifications

• Bachelor’s degree in Computer Science, Computer Information Systems, or related field.
• 7+ years of enterprise network engineering experience in data center environments.
• CCNP/CCIE or equivalent certifications preferred.
• Experience with ISO 27001 and Cyber Essentials Plus compliance environments.

Responsibilities

• Lead design, implementation, and support of enterprise network infrastructure across UK data centers and offices.
• Implement FortiGate firewalls, FortiADC load balancers, and Dell switching with high availability.
• Design core routing using OSFP and VLAN segmentation for secure networks.
• Provide secure VPN access for administrative and operational use.
• Troubleshoot routing, switching, firewalls, and load balancing platforms.
• Support monitoring, logging, and incident response for network events.

Skills

Core Networking

TCP/IP fundamentals

Routing & Switching

VPN & remote access

Network security

Education

Bachelor’s degree in CS / related field

CCNP/CCIE or equivalent

Tools

FortiGate

FortiADC

Dell Networking

Job description

Job Summary:As a Senior Network Engineer, you will lead the design, implementation, and support of enterprise network infrastructure across our UK data center and office environments. This role is focused on data center networking, load balancing, and core network services, ensuring high availability, performance, and security across all platforms.Job Description:Exciting Opportunity: Senior Network EngineerAre you a seasoned network professional ready to lead the design, implementation, and evolution of enterprise network infrastructure? We are seeking a Senior Network Engineer to drive the planning, deployment, and optimization of our critical IT and security platforms. In this role, you’ll architect solutions, mentor team members, and ensure the seamless delivery of secure, reliable services across the organization.About Us:Join a forward-thinking company committed to pushing the boundaries of technology and driving innovation. Our team is made up of passionate individuals who thrive in a collaborative environment and are dedicated to shaping the future of our industry.Your Role:As a Senior Network Engineer, you will lead the design, implementation, and support of enterprise network infrastructure across our UK data center and office environments. This role is focused on data center networking, load balancing, and core network services, ensuring high availability, performance, and security across all platforms.What You’ll Do:Strategic Support & Risk AwarenessProactively identify operational risks, performance issues, and security gaps within network and infrastructure environmentsMonitor trends, alerts, and emerging technologies to support continuous improvement of network reliability and securityContribute technical input to infrastructure and network strategy under the direction of IT leadershipNetwork Design & ImplementationDesign, configure, and support enterprise network infrastructure across UK-based data centers and officesImplement and maintain FortiGate firewalls, including policies, NAT, and high-availability configurationsDeploy and support FortiADC load balancers, including application delivery, traffic distribution, and high-availability designsConfigure and manage Dell L2/L3 switching environments, including VLANs, trunking, and inter-VLAN routingDesign and maintain core routing architecture using protocols such as OSPFProvide secure VPN access into the data center for administrative and operational accessOperations & TroubleshootingProvide advanced troubleshooting across routing, switching, firewalls, and load balancing platformsSupport network monitoring, logging, and alerting to ensure high availability and performanceParticipate in incident response and root cause analysis for network-related outagesSecurity & ComplianceImplement and maintain network security controls aligned with ISO 27001 and Cyber Essentials PlusEnsure proper segmentation, VLAN design, and access controls across environmentsSupport audit activities through documentation, configurations, and evidence collectionChange Management & DocumentationSupport network connectivity for co-located UK data center environmentsManage cross-connects, switching infrastructure, and carrier handoffsEnsure resilient and redundant network designs aligned to production requirementsFortinet Firewalls (FortiGate)FortiADC (load balancing and application delivery)Dell networking (Layer 2 / Layer 3 switching platforms)Routing (OSPF)VLAN design and network segmentationLayer 2 / Layer 3 switchingWhat You Bring to the Role:Education:Bachelor’s degree in Computer Science, Computer Information Systems, or related field.Relevant certifications such as CCNP, CCIE, CISSP, or equivalent are preferred.Experience:7+ years of enterprise network engineering experience in data center-centric environmentsStrong hands-on experience with:Deep experience with:Experience supporting high-availability network architecturesExperience supporting ISO 27001 and Cyber Essentials Plus compliance environmentsExperience working in 24x7 production environments with on-call responsibilitiesSkills:Core NetworkingAdvanced TCP/IP networking fundamentalsRouting, switching, VLANs, and segmentationDell switch configuration and troubleshootingLoad Balancing & Application DeliveryFortiADC configuration and supportTraffic distribution, persistence, health checks, and high availabilityFirewall & SecurityFortiGate configuration, NAT, policy management, logging, and high availabilityNetwork segmentation and access controlConnectivitySecure remote access via VPN for administrative and operational useWork Environment:This position offers remote-first flexibility, with hybrid or on-site options available. Occasional travel to offices or vendor sites may be required based on project needs.Why You’ll Love It Here:Strategic Impact: Lead mission-critical IT projects with direct visibility to senior leadership.Ownership & Autonomy: You’ll own the project plan — and the outcome.Collaborative Team: Work closely with experienced IT, business, and R&D professionals who value structure and results.Flexibility & Growth: Enjoy a flexible work environment with room for continued professional development.Ready to lead strategic IT projects with precision and impact? Apply now and help shape the future of our infrastructure and operations.We are committed to building a diverse and inclusive team where everyone feels empowered to contribute and grow. If you meet most of the qualifications and are excited about the role, we encourage you to apply.Worker Type:RegularNumber of Openings Available:1