Senior Systems Administrator - MS Exchange

Leidos•Fort Belvoir, VA

About The Position

Leidos is seeking an experienced Senior System Administrator with team leadership and Microsoft Exchange skills to support the DTRA I3TS Infrastructure Services team to support, maintain and optimize critical mission operations across multiple geographic locations. The ideal candidate will be a technical expert responsible for installation, configuration, security, operation, and maintenance of servers, equipment, and software related to Microsoft Windows server and Exchange. Candidates must demonstrate a high degree of problem-solving ability in a complex environment and be able to communicate effectively, both to the customer and to team members. Primary Responsibilities: Lead a team of seven or more System Administrators with Windows expertise to fulfill DoW customer requirements in a fast-paced, challenging work environment Perform OS installation, configuration, hardening, and patching in compliance with DoD STIGs and agency policies. Monitor and tune system performance, conduct root cause analysis, and resolve complex issues quickly and efficiently. Oversee and maintain automation scripts and infrastructure as code (Ansible, PowerShell, Bash, etc.). Implements Windows based security, including but not limited to group permissions, file / folder permissions, group policies, local security policies, etc. Manage user accounts, credentials, permissions, access rights, storage allocations, and active directory administration. Monitor system performance and respond to alerts. Coordinate with customers and stakeholders to collect data, conduct analysis, develop, and implement solutions associated with incident tickets and requirements. Design, implement, and maintain Active Directory enterprise environments including: Active Directory Domain Services (AD DS). Group Policy design and governance. DNS and DHCP services. Directory replication and trust models. Install, configure, and upgrade Exchange Server environments and Active Directory. Monitoring server health, mail flow, and database integrity to ensure high availability. Create/manage mailboxes, shared mailboxes, distribution groups, and manage user access and permissions. Resolve complex email, mail routing, and client connectivity issues. Be able to work in a fast-paced environment and must be able to work independently. Work on multiple projects, leading projects that fall within the Area of responsibility. Communicate with internal team members across multiple areas and client team members. Provide support on a M-F business hours schedule, also responsible for on-call, extended hour, and weekend support as required by mission or emergency situations. Create, maintain, and implement detailed documentation and maintain standard operating procedures.

Requirements

BS with 8-10 years, or MS degree with 6-8 years of experience in IT operations working with Windows, Linux servers and Virtualization.
Must hold a Top Secret/SCI Clearance.
Experience administering Microsoft Exchange Server.
Strong experience implementing and maintaining Security Technical Implementation Guides (STIGs).
Document STIG configurations and remediation actions to ensure audit readiness.
Conduct regular STIG compliance checks using tools like SCAP Compliance Checker and STIG Viewer.
Proficiency in PowerShell scripting and automation.
Strong problem-solving, analytical skills, and ability to work independently or in a team.
Hands-on experience administering Windows network environments.
DoD 8570 IAT Level II or III certification (e.g., Security+ CE, CASP+, CISSP).
Experience supporting IC or DoD classified environments.

Nice To Haves

Microsoft certifications (MCSA, MCSE, Azure Administrator Associate)
Experience with automation and scripting (Ansible, Bash, PowerShell, Python).
Expert level knowledge on Active Directory, DNS, DHCP, Group Policy Object (GPO), Microsoft Clustering, domain architecture and performance tuning.
Working knowledge of virtualization, VMWare, or equivalent.
Experience supporting classified networks or cross-domain environments

Responsibilities

Lead a team of seven or more System Administrators with Windows expertise to fulfill DoW customer requirements in a fast-paced, challenging work environment
Perform OS installation, configuration, hardening, and patching in compliance with DoD STIGs and agency policies.
Monitor and tune system performance, conduct root cause analysis, and resolve complex issues quickly and efficiently.
Oversee and maintain automation scripts and infrastructure as code (Ansible, PowerShell, Bash, etc.).
Implements Windows based security, including but not limited to group permissions, file / folder permissions, group policies, local security policies, etc.
Manage user accounts, credentials, permissions, access rights, storage allocations, and active directory administration.
Monitor system performance and respond to alerts.
Coordinate with customers and stakeholders to collect data, conduct analysis, develop, and implement solutions associated with incident tickets and requirements.
Design, implement, and maintain Active Directory enterprise environments including: Active Directory Domain Services (AD DS). Group Policy design and governance. DNS and DHCP services. Directory replication and trust models.
Install, configure, and upgrade Exchange Server environments and Active Directory.
Monitoring server health, mail flow, and database integrity to ensure high availability.
Create/manage mailboxes, shared mailboxes, distribution groups, and manage user access and permissions.
Resolve complex email, mail routing, and client connectivity issues.
Be able to work in a fast-paced environment and must be able to work independently.
Work on multiple projects, leading projects that fall within the Area of responsibility.
Communicate with internal team members across multiple areas and client team members.
Provide support on a M-F business hours schedule, also responsible for on-call, extended hour, and weekend support as required by mission or emergency situations.
Create, maintain, and implement detailed documentation and maintain standard operating procedures.