Senior Infrastructure & Network Systems Engineer

Galldris Group

Location: Enfield, Middlesex, EN3 7FJ

An exciting opportunity has arisen for a Senior Infrastructure & Network Systems Engineer to join our Head Office team based in Enfield, Middlesex. The Senior Infrastructure & Network Systems Engineer will design, operate, and secure a modern hybrid IT environment spanning on‑prem, remote office, and cloud platforms. This is a hands‑on, internal ‑based role suited to someone who enjoys working across multiple technologies while maintaining strong security and reliability standards.

Key Responsibilities:

• Design, implement, and support Linux and Windows Server environments (Windows Server 2022+).
• Manage and maintain virtualisation platforms, including Proxmox, ensuring high availability and performance.
• Administer cloud-hosted infrastructure and integrate on-premises systems with cloud-based identity and access management solutions.
• Support and maintain Microsoft 365 and Exchange environments, including both cloud and hybrid deployments.
• Deliver and manage secure web services using IIS and associated technologies.

Storage, Backup & Data Services

• Take ownership of enterprise storage and data services, including TrueNAS environments.
• Manage file services, backup solutions, disaster recovery processes, and business continuity requirements.
• Ensure data integrity, availability, and recovery capabilities are maintained to a high standard.

Identity & Access Management

• Administer authentication, authorisation, and access control solutions across multiple platforms.
• Develop and manage RADIUS policies to support secure network access.
• Oversee Public Key Infrastructure (PKI) and certificate lifecycle management, ensuring secure certificate-based authentication and encryption practices.
• Design, implement, and support secure enterprise networks using Cisco and Ubiquiti technologies.
• Configure and maintain VLAN segmentation, VPN connectivity, M-LAG, and LACP solutions.
• Troubleshoot complex networking issues and optimise network performance across multiple sites.
• Contribute to the development and ongoing enhancement of an in-house Kubernetes platform.
• Support containerised workloads, platform services, storage integration, and certificate management within Kubernetes environments.
• Collaborate with technical teams to improve scalability, automation, and operational efficiency.

Cyber Security

• Champion a security-first approach across all infrastructure and network services.
• Apply Zero Trust and defence-in-depth security principles throughout the IT estate.
• Support ISO 27001-aligned operations and contribute to security hardening, monitoring, vulnerability management, and incident response activities.

Qualifications/ Experience/Knowledge:

• Extensive knowledge of Windows Server infrastructure (2022 and later).
• Experience supporting hybrid cloud and Microsoft technology environments.
• Strong understanding of networking principles and protocols.
• Experience with Cisco and/or Ubiquiti networking technologies.
• Knowledge of authentication, identity management, and PKI solutions.
• Experience managing enterprise backup and disaster recovery solutions.
• Strong troubleshooting and problem-solving skills.
• Excellent documentation and technical communication abilities.
• CompTIA Network+ or equivalent networking qualification.
• Experience with Proxmox virtualisation.
• Knowledge of Kubernetes and containerised environments.
• Experience working within ISO 27001 or other security-focused frameworks.
• Microsoft 365 and Exchange administration experience

Why work for us?

You will be joining a great team with plenty of ongoing support, training and internal development opportunities; a summary of our benefits include:

• 25 days of annual leave plus bank holidays, increasing to 29 days with length of service.
• An extra day of annual leave for your birthday.
• Access to our Salary Sacrifice Car Scheme.
• Access to a range of wellbeing resources.
• Access to private medical insurance.
• Company life assurance.
• Excellent social opportunities with access to Premier League football and The O2 Arena VIP tickets.

Interested applicants must be eligible to work legally in the UK.

Employee referral scheme - refer a friend or family member to work for Galldris.

Galldris is an Equal Opportunities employer and does not discriminate against any protected characteristic.

Please note: We are not using recruitment agencies for this role. In the event of speculative CV submissions, no fees will be applicable.