Email Services Systems Administrator - TS/SCI with Polygraph

Endpoint Management Systems AdministratorOwn your opportunity to support national defense. Your work will help keep critical operations secure and connected across the global enterprise—directly, contributing to a mission that protects our nation every day.CIO Infrastructure Services (CIS) is growing, and we invite both our experienced incumbents and new team members to be part of what's next. Incumbents bring invaluable mission insight, while new talent adds fresh ideas and energy. Together, we'll strengthen continuity and drive the next generation of innovation.As an Email Services Systems Administrator supporting CIS, you will operate, secure, and optimize enterprise email and messaging services across complex multinetwork environments. You will maintain high availability email platforms, ensure reliable communication services, and sustain cloud enabled collaboration capabilities that directly support mission critical operations. Your work enhances the resilience, performance, and readiness of enterprise messaging systems relied on by users worldwide.Key Responsibilities:Administer, maintain, and troubleshoot enterprise Exchange and M365 email systems, ensuring high availability, secure operations, and reliable mail flow across multiple networksSupport email architecture components including mailbox databases, transport services, journaling, archival/retention systems, SMTP relays, and message hygiene toolsManage identity and access for messaging services, including authentication, PKI based access, mobile access policies, and integration with directory servicesMonitor system health, capacity, and performance; perform diagnostics; and implement corrective actions for service disruptions or degraded functionalitySupport migrations, upgrades, and sustainment of both on premise and cloud based messaging platforms, ensuring seamless integration and minimal user impactExecute backup, recovery, and failover operations for Exchange systems and related messaging components, validating resilience and continuity of operationsTroubleshoot complex issues involving authentication, DNS, PKI, mobile clients, cross domain routing, and dependencies across hybrid environmentsMaintain documentation, SOPs, service configurations, and operational artifacts supporting sustainment, change management, and continuous improvementApply security patches, cumulative updates, and platform hotfixes across Exchange, M365, and messaging related infrastructure to maintain compliance and secure service baselinesIdentify and remediate noncompliant messaging systems by reviewing vulnerability and SCAP reports, resolving patch exceptions, and validating corrective actions across messaging environmentsWhat You'll Need to Succeed:Experience Requirements: Email Services Systems Administrator Senior - Requires a Bachelor's degree in an IT-related field or 8+ years of relevant IT experience in lieu of a degree. Email Services Systems Administrator Principal - Requires a Bachelor's degree in an IT-related field or 10+ years of relevant IT experience in lieu of a degree. Email Services Systems Administrator Sr. Principal - Requires a Bachelor's degree in an IT-related field or 12+ years of relevant IT experience in lieu of a degree.Clearance: Active TS/SCI clearance with a favorable PolygraphCertifications: Meet DoD 8140 Information Assurance Workforce certification requirements (e.g., Security+ CE)Hands-on experience administering Exchange (on-premises) and M365 messaging services in enterprise or multi-network environmentsStrong proficiency with email routing, SMTP, DNS, authentication, certificates, and mobile/remote email accessExperience with secure configuration, retention/archival policies, and compliance requirements for enterprise messagingFamiliarity with patching, vulnerability remediation, and configuration compliance for messaging platformsAbility to diagnose and resolve complex messaging, access, routing, and authentication issues across hybrid environmentsStrong documentation, communication, and cross team collaboration skillsUS citizenship requiredLocation: OnsiteGDIT is your place At GDIT, the mission is our purpose, and our people are at the center of everything we do. Growth: AI-powered career tool that identifies career steps and learning opportunities Support: An internal mobility team focused on helping you achieve your career goals Rewards: Comprehensive benefits and wellness packages, 401K with company match, and competitive pay and paid time off Community: Award-winning culture of innovation and a military-friendly workplace OWN YOUR OPPORTUNITY Explore an enterprise IT career at GDIT and you'll find endless opportunities to grow alongside colleagues who share your desire to drive operations forward.The likely salary range for this position is $96,569 - $130,651. This is not, however, a guarantee of compensation or salary. Rather, salary will be set based on experience, geographic location and possibly contractual requirements and could fall outside of this range.Scheduled Weekly Hours: 40Travel Required: NoneTelecommuting Options: OnsiteWork Location: USA MD Annapolis JunctionAdditional Work Locations: USA CO Colorado Springs - 8610 Explorer Dr (COC036), USA DC Washington, USA VA Springfield - 7770 Backlick Rd (VAS110) General Dynamics Information Technology