IT System Administrator

Senior IT Systems AdministratorLocation: Gloucestershire, UK (On-Site)Employment Type: Full-time, Mid-Senior levelAbout the OpportunitySanderson is collaborating with a leading global technology organisation that delivers mission-critical services in secure environments for government and national security clients. The team is expanding and seeking a skilled Senior IT Systems Administrator to join a high-performance environment supporting critical infrastructure operations.In this role, you’ll work across multiple teams to ensure stability, performance, and compliance across enterprise systems — maintaining secure IT environments and helping drive continual service improvement through innovation and best practice.Key ResponsibilitiesProvide 1st and 2nd line technical support across complex IT environmentsMonitor system performance to ensure uptime, reliability, and efficiencyDevelop, maintain, and update system documentationImplement and enforce operational standards, policies, and proceduresSupport compliance initiatives and internal process improvementsEssential Skills & ExperienceStrong background in Windows Server Administration (2016/2019)Experience working to ITIL best practicesExcellent organisational and time management skillsAnalytical mindset with a proactive approach to identifying risks and improvementsStrong communication and collaboration skills, with a willingness to share and learnDesirable Technologies & ExperienceInstallation, upgrade, configuration, and support experience with Windows Server, AWS, and AzureStrong understanding of Active Directory (object creation, OU management, RBAC, DFS)Knowledge of virtualisation technologies: VMware, vSphere, vSAN, SCVMM, Hyper-VFamiliarity with containerisation tools and technologiesNetworking fundamentals: TCP/IP, DHCP, DNS, LAN/WANScripting experience in PowerShellAwareness of McAfee EPO/ENS security toolsSecurity Clearance RequirementsDue to the nature of the work, candidates must be eligible for national security clearance. To meet this requirement, applicants must:Be sole British citizens (dual nationality is not permitted)Have not spent more than 30 consecutive days outside the UK in the past 10 yearsHave no criminal recordHave no significant financial irregularities (e.g. bankruptcy, unpaid debt)Unfortunately, candidates who do not meet these criteria cannot be considered for this position.Why You’ll Enjoy Working HereCompetitive salary and comprehensive benefits packageHybrid working model balancing flexibility and collaborationCareer growth opportunities through continuous learning and developmentWork on high-impact, nationally significant projectsInclusive, people-first culture focused on wellbeing and professional excellence