Senior Infrastructure Engineer

About the role

We are looking for a versatile and experienced Senior Infrastructure Engineer to join our team based from Abbey Wood, Bristol. This role benefits from our 4xFlex working pattern, offering a 4-day working week Monday - Thursday and hybrid working, with typically 2 days a week onsite and 2 days working from home (subject to business needs)

As a Senior Infrastructure Engineer, you will be responsible for the design, implementation, and high-availability management of our core physical infrastructure. Your primary focus will be the architecture and stability of our Cisco-centric networking environment, specifically supporting our local data centers and distributed office sites. You will ensure that the foundational connectivity linking our data center resources to our various office locations-is high-performing, secure, and resilient. You will act as the subject matter expert for all networking components, managing the full lifecycle of hardware from procurement and deployment to maintenance and decommissioning. You will work closely with the systems and security teams to ensure a hardened, reliable, and scalable physical infrastructure.

Key Responsibilities:

• Data Center Infrastructure: Design and maintain high-performance data center network fabrics using Cisco Nexus and Catalyst platforms.
• Site Connectivity: Manage and optimize the connectivity between data centers and distributed office sites, ensuring reliable WAN/LAN performance.
• Routing & Switching: Configure and troubleshoot complex routing (BGP, OSPF, EIGRP) and switching (VLANs, STP) environments.
• Network Security: Implement and maintain perimeter and internal security through robust firewall management.
• Hardware Lifecycle Management: Lead hardware refreshes, firmware upgrades, and capacity planning for all physical networking assets.
• Incident Management: Act as the highest escalation point for network-related outages, performing deep-packet analysis and root-cause analysis.
• Documentation & Standards: Maintain rigorous documentation of physical topologies, IP addressing schemes, and configuration standards.

The successful candidate must achieve the appropriate level (DV) of security clearance. More details can be found here

Required skills, qualifications and experience

• Bachelor’s degree in Computer Science, Network Engineering or equivalent professional experience.
• Significant hands-on experience in enterprise-level infrastructure or network engineering.
• Proven experience managing Cisco infastrucuture switches and data center-grade routing/switching.
• Expert knowledge of Layer 2 and Layer 3 protocols.
• Strong understanding of WAN technologies, VPNs (IPsec), and site-to-site connectivity protocols.
• Advanced ability to use CLI-based diagnostic tools and protocol analyzers (e.g., Wireshark) to resolve complex physical layer and protocol issues.

Desired Skills

• Cisco Professional or Expert level certifications (CCNA, CCNP or CCIE).
• Experience leveraging automation and scripting to streamline repetitive configuration tasks, firmware deployments, and lifecycle management across data centers and office sites.
• Experience managing and optimizing advanced WAN architectures to ensure seamless connectivity between office sites and data centers.
• Experience with structured cabling standards, rack layouts, and power/cooling considerations for data center environments.