Infrastructure Engineer -

Infrastructure EngineerRate: up to £530 per day (Umbrella only)Clearance Required: BPPSDuration: 6 monthsLocation: Manchester or Inverness, 5 days onsiteWe are seeking an experienced Senior Identity Infrastructure Engineer to support and maintain the core identity infrastructure platforms that underpin the organisation's Identity and Access Management (IDAM) services.The successful candidate will be responsible for the administration, support, security, and continuous improvement of the Active Directory, PKI, DNS, Group Policy, and authentication infrastructure. They will work closely with the wider IDAM team, supporting critical identity services and providing L2/L3 operational support across the identity estate where required.This role requires a highly capable infrastructure engineer with deep expertise in Microsoft Active Directory and Public Key Infrastructure (PKI), combined with a strong understanding of enterprise identity technologies and authentication services.The position is based within secure facilities in either Inverness or Manchester, working closely with security, engineering, and IDAM teams to ensure the availability, resilience, and security of critical identity platforms.Key ResponsibilitiesAdminister and maintain enterprise Active Directory forests, domains, and domain controllers.Manage Active Directory Sites and Services, replication topology, trusts, and directory services infrastructure.Administer AD-integrated DNS and support authentication services across the enterprise.Manage and maintain Group Policy architecture, including policy design, implementation, troubleshooting, and lifecycle management.Support Active Directory backup, recovery, disaster recovery, and business continuity processes.Monitor platform health, performance, security, and replication.Support Active Directory upgrades, migrations, consolidation projects, and infrastructure improvements.Implement and maintain Active Directory security hardening standards and privileged access controls.Public Key Infrastructure (PKI)Administer and support Microsoft Active Directory Certificate Services (AD CS).Manage Certificate Authorities, certificate templates, certificate enrolment, and certificate lifecycle processes.Support Offline Root CA and Issuing CA infrastructure.Administer Certificate Revocation Lists (CRL), Authority Information Access (AIA), and certificate distribution services.Monitor certificate compliance, renewals, revocations, and expiration management.Maintain PKI operational documentation, recovery procedures, and security standards.Support cryptographic and certificate-related troubleshooting across infrastructure and security platforms.Identity Infrastructure & Authentication ServicesSupport Microsoft Entra Connect and hybrid identity infrastructure.Maintain LDAP, LDAPS, Kerberos, and NTLM authentication services.Support integrations between Active Directory and enterprise identity platforms including MIM, Entra ID, Okta, and BeyondTrust.Assist with identity-related service improvements and platform optimisation initiatives.Support authentication, directory, and identity infrastructure incidents through to resolution.Work collaboratively with the IDAM engineering team to support critical identity lifecycle services.IDAM Support ActivitiesProvide L2/L3 support for identity-related incidents and service requests.Assist with troubleshooting user provisioning, synchronisation, and authentication issues.Support MIM, Entra ID, Okta, and BeyondTrust integrations where infrastructure expertise is required.Collaborate with IDAM engineers to investigate root causes and implement long-term solutions.Support operational activities across the wider identity ecosystem during periods of increased demand.Automation & Continuous ImprovementDevelop and maintain PowerShell automation for identity infrastructure administration.Drive service improvements, platform optimisation, and operational efficiencies.Contribute to security improvement initiatives, vulnerability remediation, and infrastructure modernisation.Produce and maintain technical documentation, operational procedures, and support runbooks.Essential Experience / SkillsExtensive hands-on experience administering enterprise Active Directory environments.Strong knowledge of: Active Directory Domain Services (AD DS)Active Directory Sites and ServicesForest and Domain AdministrationDNSGroup PolicyLDAP / LDAPSKerberos AuthenticationTrusts and ReplicationAD Backup and RecoveryExperience troubleshooting complex authentication and directory service issues.PKIStrong experience administering Microsoft Active Directory Certificate Services (AD CS).Experience managing: Certificate AuthoritiesCertificate TemplatesCRL and AIA InfrastructureCertificate Lifecycle ManagementCertificate Enrolment ServicesKey Recovery and ArchivalExperience supporting enterprise PKI environments.Infrastructure PlatformsWindows Server 2016/2019/2022 administration.PowerShell scripting and automation.Security hardening and privileged administration.High Availability and Disaster Recovery planning.Infrastructure monitoring and operational support.Identity TechnologiesWorking knowledge of:Microsoft Entra IDMicrosoft Entra Connect / Cloud SyncMicrosoft Identity Manager (MIM)OktaBeyondTrustUnderstanding of:Identity and Access Management (IAM)Joiner, Mover, Leaver ProcessesIdentity Lifecycle ManagementAuthentication and AuthorisationAccess GovernanceRole-Based Access Control (RBAC)If you receive suspicious outreach claiming to be from us, please contact us via the ManpowerGroup website.TPBN1_UKTJ