Senior Infrastructure Consultant

Role Overview: We are seeking a Senior Infrastructure Consultant to provide senior-level consultancy, operational support, and technical leadership across complex customer environments. The role will span on-premises, hybrid, and cloud technologies, including Exchange, Microsoft 365, Azure, Windows Server, Citrix, virtualisation, backup, networking, monitoring, and security. The successful candidate will act as a senior technical escalation point, lead technical discovery and solution delivery, maintain high-quality documentation, and drive service reliability and continuous improvement. Due to the nature of the customer environments supported, candidates must be eligible to obtain UK Security Check (SC) clearance. Provide senior consultancy and infrastructure support across multiple managed service customers and technologies. Act as a technical escalation point for Microsoft Exchange, Exchange Online, Citrix, Windows Server, identity, virtualisation, networking, backup, monitoring, and cloud-related incidents and service requests. Support, administer, troubleshoot, and improve Microsoft Exchange Server, hybrid Exchange, Exchange Online, migrations, mail flow, security, availability, and disaster recovery. Support and optimise Citrix environments, including Virtual Apps and Desktops, StoreFront, Delivery Controllers, Citrix Gateway or ADC, profile management, application delivery, and associated infrastructure. Work with customers and internal teams to gather requirements, complete technical discovery, produce solution designs, implement changes, and deliver service improvements. Support hybrid and on-premises environments including VMware, Hyper-V, Windows Server, Active Directory, DNS, DHCP, Microsoft 365, Azure, backup, storage, and network services. Plan and deliver infrastructure upgrades, migrations, patching, lifecycle activities, resilience improvements, and remediation work with appropriate testing and rollback arrangements. Maintain technical designs, operational documentation, runbooks, support procedures, asset information, and knowledge articles. Operate within structured ITIL and ISO 20000 service management processes, including incident, problem, change, request, and configuration management. Mentor engineers, share knowledge, and provide clear customer-facing updates on incidents, changes, risks, recommendations, and delivery progress. Follow customer security requirements and support work in environments requiring UK Security Check clearance. 7+ years’ experience in enterprise infrastructure consultancy, engineering, managed services, or technical operations. Strong hands-on knowledge of Microsoft Exchange Server and Exchange Online, including hybrid configuration, migrations, mail flow, security, high availability, and troubleshooting. Strong hands-on knowledge of Citrix technologies in enterprise environments, ideally including Citrix Virtual Apps and Desktops, StoreFront, Delivery Controllers, Citrix Gateway or ADC, and profile management. Broad experience supporting on-premises and hybrid infrastructure, including Windows Server, Active Directory, Group Policy, DNS, DHCP, VMware or Hyper-V, storage, backup, and networking. Practical experience with Microsoft 365 and Azure services, with the ability to support integration between cloud and on-premises platforms. Proven ability to analyse and resolve complex issues across messaging, end-user computing, identity, server, virtualisation, networking, monitoring, and security domains. Experience leading technical discovery, producing designs and implementation plans, assessing risks and dependencies, and delivering controlled infrastructure changes. Strong understanding of ITIL practices and experience working within a controlled managed service or enterprise environment. Strong customer-facing communication, stakeholder management, technical documentation, and knowledge-transfer skills. Ability to work independently, prioritise competing demands, manage escalations, and support multiple customer environments concurrently. Mandatory: Eligible to obtain and maintain UK Security Check (SC) clearance. Appointment and assignment to relevant customer work may be subject to successful vetting. Relevant Microsoft, Citrix, VMware, ITIL, security, or cloud certifications are desirable. Technical Skills Microsoft Exchange Server and Exchange Online: architecture, administration, cumulative updates, hybrid configuration, mail flow, connectors, transport rules, certificates, public folders, high availability, backup, recovery, migrations, and troubleshooting. Citrix Virtual Apps and Desktops: Delivery Controllers, StoreFront, Machine Creation Services or Provisioning Services, Citrix Gateway or ADC, policies, profiles, image management, application publishing, monitoring, and troubleshooting. Windows Server administration, Active Directory, Group Policy, DNS, DHCP, file and print services, patching, clustering, certificate services, and PowerShell. Micr…