Tier 3 System Admin Lead

DMI is a leading provider of digital services and technology solutions, headquartered in Tysons Corner, VA. With a focus on end-to-end managed IT services, including managed mobility, cloud, cybersecurity, network operations, and application development, DMI supports public sector agencies and commercial enterprises around the globe. Recognized as a Top Workplace, DMI is committed to delivering secure, efficient, and cost-effective solutions that drive measurable results. Learn more at www.dminc.com

DMI, LLC is seeking a Tier 3 System Administrator Lead who is accountable for the operational integrity of all servers across on-premises, virtual, and cloud environments. This role serves as the senior technical authority for systems administration, providing expert-level incident investigation and recovery across a mixed infrastructure that includes physical and virtual servers, AWS cloud instances, and enterprise storage solutions (PowerScale and Cohesity). The position supports 24x7x365 availability and partners directly with customer IT staff on systems health, security posture, and change management.

• → Maintain operational integrity of all on-premises, virtual, and cloud servers including patching, scaling, firmware upgrades, and hardware failure resolution• Administer Active Directory including FSMO role health, domain controller replication, SYSVOL integrity, DNS/SRV record validation, and directory services database maintenance• Manage AWS infrastructure including EC2 instance lifecycle, S3 bucket policies and lifecycle rules, Route 53 DNS and VPC routing, Lambda monitoring, and CloudWatch performance remediation• Administer enterprise storage environments including PowerScale and Cohesity; perform proactive monitoring and capacity management• Execute shell scripting for Linux/Windows administration tasks; maintain and update baseline system configurations in compliance with customer Standard Operating Environment (SOE)• Lead Tier 3 incident investigation and root cause analysis for Priority 1 and Priority 2 server and systems outages; provide technical direction to Tier 1/2 staff on escalated issues• Coordinate with customer IT Security on NIST-compliant controls, patch prioritization, and vulnerability remediation• Support data center operations including equipment racking, asset labeling, hardware decommissioning, and infrastructure documentation maintenance

Applicants selected may be subject to a government security investigation and must meet eligibility requirements for access to classified information. US citizenship may be required for some positions.

• Expertise in Linux and Windows server administration, including advanced command-line troubleshooting and shell scripting
• Hands-on experience with AWS (EC2, S3, Route 53, VPC, Lambda, CloudWatch); AWS SysOps Administrator-level proficiency preferred
• Experience administering Active Directory in multi-site enterprise environments
• Familiarity with enterprise storage platforms (PowerScale, Cohesity preferred)
• Experience operating within an ITIL 4 service management framework
• AWS Certified SysOps Administrator or equivalent preferred