Senior Network Engineer in Preston

Reporting to the Network Manager, the Senior Network Engineer will play a critical role in delivering secure, high-performing, and resilient network services across Sysco. The primary objective of this role is to support and optimise Sysco’s enterprise network infrastructure while ensuring operational excellence across a complex, multi-site environment.

This role involves working closely with the Sysco Global Network team and a range of cross-functional stakeholders to ensure that network operations, engineering activities, and project delivery remain aligned with organisational standards and business requirements. You will be responsible for maintaining and enhancing a broad array of technologies across LAN, WAN, wireless, security, VPN, load balancing, cloud networking, and automation, ensuring the seamless operation of network services across the estate.

This position is offered on a hybrid basis from our Dublin office (D11 VP3F) or Limerick office (V42 XC04), with flexibility to support campus environments, remote sites, and data centres as needed.

You will maintain and support critical network components across a large enterprise landscape, ensuring the reliability and stability of environments built on Cisco Catalyst and Cisco Nexus platforms, alongside VSS and StackWise/FlexStack technologies. Your work will involve monitoring and troubleshooting routing and switching environments that rely on protocols such as OSPF, EIGRP, BGP and IBGP, as well as delivering robust performance across VLAN and VRF-based network designs.

The role will require hands-on support of a diverse security estate, including Cisco ASA multi-context firewalls, Check Point firewalls, content-filtering technologies, and associated security controls. You will help safeguard the organisation by applying strong network security practices across all services, from campus wireless to VPN and remote access environments.

You will take ownership of wireless services built on Cisco Wireless Controllers and Motorola wireless technology, ensuring stable and high-quality connectivity across the enterprise. You will also support load balancing and optimisation technologies such as F5, Bluecoat proxy services, QoS-driven voice and video environments, and WAN optimisation platforms including Cisco WAAS.

Day-to-day, you will provide technical support via ServiceNow, performing incident resolution, problem isolation, and root-cause analysis across LAN, WAN, security, wireless, VPN and load-balancing services. You will be expected to provide operational insight into complex issues, often using diagnostic tools such as SolarWinds, Infoblox, packet capture and trace analysis utilities, and other SNMP-based monitoring platforms. Strong documentation capability using Visio is required.

The role will also involve contributing to network projects from design through to deployment, across traditional infrastructure and cloud-based environments including AWS, Azure and virtualised platforms. Experience with automation and scripting, particularly using Python, will be valuable in supporting Sysco’s drive towards standardisation and efficiency.

You will deliver regular updates to PMO teams, leadership, and operational stakeholders, ensuring transparency and alignment across all network activities. Supporting remote sites, corporate data centres, and campus environments will form part of your remit, alongside participation in the global on-call rotation to ensure continuity of service.

You will bring extensive experience supporting large-scale enterprise networks, with deep knowledge of Cisco-based infrastructure, modern routing and switching practices, wireless environments, firewall and security technologies, cloud networking, and load balancing. You must be confident operating with considerable independence, applying strong analytical thinking and technical judgement to diagnose and resolve complex issues.

We are looking for someone with vast hands-on experience in network engineering, preferably supported by a degree in Computer Science or an equivalent discipline, or significant practical experience. Long-held Cisco certifications such as CCNP or CCIE are highly desirable, as is experience working across diverse technologies and large multi-site environments. Strong communication, documentation, and stakeholder engagement skills are essential, alongside the ability to work collaboratively within a global team.