Senior Infrastructure & Network Systems Engineer in London

• Senior Infrastructure & Network Systems Engineer
• Galldris Group
• 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

• Infrastructure & Cloud Management
• 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 True NAS 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.
• Network Engineering
• 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.
• Kubernetes & Platform Engineering
• 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

Essential Criteria

• Strong Linux administration experience.
• 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.

Desirable Criteria

• Comp TIA 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.
• Minimum 6% pension contribution.
• 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.

Should you feel you have what it takes to be successful in this role, then we would love to hear from you.

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.