Network Engineer - CCNA/CCNP

CBSbutler Holdings Limited trading as CBSbutler; Cambridge; On-site; GBP 74,000 - 81,000; Full time

Job summary

CBSbutler Holdings Limited trading as CBSbutler is seeking an experienced Network Contractor to support a major Main Campus Network Redesign and remediation programme in Cambridge.

This is an onsite role in Cambridge with planned evening and weekend change windows, requiring hands-on Cisco routing and switching, OSPF, BGP and wireless expertise to improve network stability, resilience and standardisation.

Qualifications

• CCNA or demonstrable Cisco networking experience.
• Strong Cisco routing and switching background.
• Practical OSPF and working BGP experience.
• Enterprise campus network experience.
• Strong network troubleshooting skills.
• Experience cleaning up and standardising legacy configurations.
• Cisco wireless knowledge and Aruba experience.
• Experience working under formal change-control processes.
• Strong technical documentation skills.
• Ability to work onsite in Cambridge.
• Flexibility to support planned evening/weekend changes.

Responsibilities

• Review existing campus network topology and configurations.
• Identify and remediate legacy, redundant, inconsistent or obsolete configuration.
• Support network redesign and logical simplification.
• Configure and troubleshoot Cisco routers and switches.
• Troubleshoot complex Layer 2/Layer 3 connectivity and routing issues.
• Review and remediate VLANs, SVIs, trunks, port channels, routing and associated configuration.
• Support migration from legacy configurations to the agreed target design.
• Identify and remediate unused VLANs, interfaces, static routes, ACLs, prefix lists, route maps and unnecessary routing advertisements.
• Support Cisco wireless environments and troubleshoot basic Aruba networking/wireless issues.
• Prepare and implement controlled production network changes.
• Produce MOPs, implementation plans, rollback procedures and validation plans.
• Complete pre- and post-change testing and documentation.
• Produce accurate HLD/LLD, as‑built, topology, routing and operational documentation.
• Work collaboratively with internal engineering teams while operating independently when required.

Skills

Cisco Routing & Switching

OSPF

BGP

Wireless

Change Windows

Onsite Cambridge

Documentation

Job description

Network Contractor - Main Campus Network Redesign

Location: Cambridge - Onsite

Rate: £400-£440 per day, Inside IR35

Contract: Network Contractor

Working Pattern: Onsite, with planned evening/weekend change windows

We are seeking an experienced Network Contractor to support a major Main Campus Network Redesign and Remediation programme in Cambridge.

This is a hands‑on role requiring strong Cisco routing and switching, enterprise campus networking, OSPF, BGP and wireless experience. You will work alongside existing network and infrastructure teams to improve network stability, resilience, supportability and configuration standards.

Key Responsibilities

• Review existing campus network topology and configurations.
• Identify and remediate legacy, redundant, inconsistent or obsolete configuration.
• Support network redesign and logical simplification.
• Configure and troubleshoot Cisco routers and switches.
• Troubleshoot complex Layer 2/Layer 3 connectivity and routing issues.
• Review and remediate VLANs, SVIs, trunks, port channels, routing and associated configuration.
• Support migration from legacy configurations to the agreed target design.
• Identify and remediate unused VLANs, interfaces, static routes, ACLs, prefix lists, route maps and unnecessary routing advertisements.
• Support Cisco wireless environments and troubleshoot basic Aruba networking/wireless issues.
• Prepare and implement controlled production network changes.
• Produce MOPs, implementation plans, rollback procedures and validation plans.
• Complete pre- and post-change testing and documentation.
• Produce accurate HLD/LLD, as‑built, topology, routing and operational documentation.
• Work collaboratively with internal engineering teams while operating independently when required.

Technical Requirements

Cisco Routing & Switching

• Strong hands‑on Cisco enterprise networking experience.
• Excellent Layer 2/Layer 3 and TCP/IP knowledge.
• VLANs, trunks, SVIs, port channels and Spanning Tree.
• Enterprise campus network design and resilient network architectures.
• Network configuration remediation and standardisation.

OSPF

• Practical configuration and troubleshooting experience.
• Neighbour relationships, areas, route advertisement and summarisation.
• Path selection, costs, default routes and redistribution.

BGP

• Working knowledge of eBGP/iBGP.
• Neighbour configuration and route advertisement.
• Prefix lists, route maps & filtering.
• Path selection, Local Preference, MED and AS Path.
• Troubleshooting BGP neighbour and routing issues.

Wireless

• Cisco Wireless LAN Controllers, APs, WLANs/SSIDs and VLAN integration.
• Enterprise wireless and client connectivity troubleshooting.
• Working knowledge of Aruba networking and/or wireless environments.

Change & Out-of-Hours Working

The contractor will participate in planned production changes and migrations, including:

• Change planning, risk assessment and implementation documentation.
• MOPs and rollback procedures.
• Pre/post-change validation.
• Troubleshooting during implementation.
• Planned evening and weekend maintenance windows.

Out-of-hours work will be agreed in advance wherever reasonably possible.

Essential Experience

• CCNA or demonstrable equivalent Cisco networking experience.
• Strong Cisco routing and switching background.
• Practical OSPF and working BGP experience.
• Enterprise campus network experience.
• Strong network troubleshooting skills.
• Experience cleaning up and standardising legacy configurations.
• Cisco wireless knowledge and Aruba networking/wireless experience.
• Experience working under formal change‑control processes.
• Strong technical documentation skills.
• Ability to work onsite in Cambridge.
• Flexibility to support planned evening/weekend changes.

Desirable: CCNP-level knowledge, Cisco Catalyst experience, campus redesign/migration experience, mixed Cisco/Aruba environments, HLD/LLD experience and exposure to network automation or configuration management