Email Services Systems Administrator - TS/SCI with Polygraph

General Dynamics Information Technology; Maryland; On-site; USD 120,000 - 150,000; Full time

Job summary

General Dynamics Information Technology seeks an Endpoint Management Systems Administrator to maintain and secure enterprise email and messaging services across multi-network environments. You will ensure high availability and seamless mail flow for users worldwide.

The role requires Exchange on-premises and M365 experience, DoD IA certifications, and strong collaboration with cross‑functional teams to sustain mission-critical operations.

Qualifications

• Bachelor’s degree in IT or 8+ years of related experience.
• Active TS/SCI clearance with a favorable polygraph.
• DoD 8140 IA certification requirements (e.g., Security+ CE).
• Hands-on experience administering Exchange (on-premises) and M365 in enterprise environments.
• Experience with hybrid messaging, DNS, PKI, and secure patches for messaging platforms.
• Strong documentation and cross-team collaboration skills.

Responsibilities

• Administer and troubleshoot Exchange and M365 to ensure high availability.
• Manage mailbox databases, transport, journaling, and retention systems.
• Control identity and access for messaging services including PKI and directory integration.
• Monitor health, diagnose issues, and perform corrective actions in hybrid environments.
• Support migrations/upgrades for on‑prem and cloud messaging platforms.
• Execute backup, recovery, and failover for Exchange systems.
• Troubleshoot DNS, PKI, cross-domain routing, and messaging dependencies.
• Maintain documentation, SOPs, and configurations for sustainment and change control.
• Apply security patches and ensure compliance baselines for messaging infrastructure.
• Remediate noncompliant messaging systems based on vulnerability reports.

Skills

Email Services

Systems Administrator

Security Clearance

Education

Bachelor’s degree or 8+ years experience

Tools

Exchange On-Premises

M365

Job description

ENDPOINT MANAGEMENT SYSTEMS ADMINISTRATOR

YOUR IMPACT

Own 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.

MEANINGFUL WORK AND PERSONAL IMPACT

As anEmail ServicesSystems Administrator supporting CIS, you willoperate, secure, andoptimizeenterprise email and messaging services across complex multinetwork environments. You will maintainhigh availabilityemail platforms, ensure reliable communication services, and sustaincloud enabledcollaboration capabilities that directly supportmission criticaloperations. 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 networks
• Support email architecture components including mailbox databases, transport services, journaling, archival/retention systems, SMTP relays, and message hygiene tools
• Manage identity and access for messaging services, including authentication,PKI basedaccess, mobile access policies, and integration with directory services
• Monitor system health, capacity, and performance; perform diagnostics; and implement corrective actions for service disruptions or degraded functionality
• Support migrations, upgrades, and sustainment of bothon premiseandcloud basedmessaging platforms, ensuring seamless integration and minimal user impact
• Execute backup, recovery, and failover operations for Exchange systems and related messaging components,validatingresilience and continuity of operations
• Troubleshoot complex issues involving authentication, DNS, PKI, mobile clients,cross domainrouting, and dependencies across hybrid environments
• Maintain documentation, SOPs, service configurations, and operational artifacts supporting sustainment, change management, and continuous improvement
• Apply security patches, cumulative updates, and platform hotfixes across Exchange, M365, andmessaging relatedinfrastructure tomaintaincompliance and secure service baselines
• Identifyand remediate noncompliant messaging systems by reviewing vulnerability and SCAP reports, resolving patch exceptions, andvalidatingcorrective actions across messaging environments

WHAT YOU’LL NEED TO SUCCEED

• EXPERIENCE REQUIREMENTS:
  Email ServicesSystems 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 ServicesSystems 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 ServicesSystems 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 Polygraph
• CERTIFICATIONS: 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 environments
• Strongproficiencywith email routing, SMTP, DNS, authentication, certificates, and mobile/ remoteemail access
• Experience with secure configuration, retention/archival policies, and compliance requirements for enterprise messaging
• Familiarity with patching, vulnerability remediation, and configuration compliance for messaging platforms
• Ability to diagnose and resolve complex messaging, access, routing, and authentication issues across hybrid environments
• Strong documentation, communication, andcross teamcollaboration skills
• US citizenship required

• LOCATION: Onsite

GDIT 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.

#CIS