Senior IT Infrastructure Lead: Networks, Servers & Microsoft 365

Sigma-Engineers-; Baton Rouge (LA); On-site; USD 95,000 - 140,000; Full time

Job summary

Sigma, founded in 1987, is a multi‑discipline engineering and design company serving petrochemical industries. The IT Infrastructure Manager will lead the reliability and security of network, server, storage, and Microsoft 365 environments, coordinating deployments, imaging, asset management, and end-user support.

This on-site role requires hands‑on leadership and project oversight across complex IT environments.

Qualifications

• Five or more years of progressive experience supporting enterprise infrastructure across networking, servers, storage, Microsoft 365, endpoints, and user support.
• Troubleshooting experience with TCP/IP networking, switching, wireless, VPN, firewalls, DNS, DHCP, VLANs, and internet connectivity.
• Hands-on experience administering Windows Server, Active Directory, Microsoft Entra ID, virtualization, storage, backup, patching, and monitoring technologies.
• Hands-on experience administering Microsoft 365 services such as Exchange Online, Teams, SharePoint Online, OneDrive, Intune, and identity services.
• Experience with computer imaging or modern provisioning, endpoint management, device refresh, and secure device retirement.
• Experience maintaining hardware and software asset records throughout the full lifecycle.
• Ability to communicate clearly with technical and nontechnical audiences and provide patient, respectful, and effective user support.
• Ability to organize competing priorities, lead incident resolution, document work, and follow through on operational and project commitments.
• Ability to participate in planned maintenance and an on‑call or after‑hours escalation rotation, as business needs require.
• Experience in Project Management. Project oversight- planning, executing, implementation and follow up, especially experience with networking projects.

Responsibilities

• Own day-to-day operation and lifecycle management of LAN, WAN, internet connectivity, firewalls, VPN services, switching, DNS, DHCP, VLANs, and network monitoring.
• Monitor network availability, capacity, performance, and security; troubleshoot outages and recurring issues; coordinate escalation with carriers, manufacturers, and service providers.
• Maintain network diagrams, configurations, standards, inventories, support contracts, and recovery procedures.
• Plan and execute network deployments, upgrades, segmentation, site openings, and technology integrations in coordination with business and security requirements.
• Administer and support physical and virtual server environments, operating systems, core infrastructure services, file services, backup platforms, and storage systems.
• Monitor system health, capacity, patching, performance, availability, and support status; identify risks and propose lifecycle or capacity improvements.
• Maintain backup, restore, disaster recovery, and business continuity procedures, including scheduled validation of recoverability.
• Coordinate hardware, software, warranty, licensing, and vendor support for server and storage platforms.
• Administer and support Microsoft 365 services, including Entra ID, Exchange Online, Teams, SharePoint Online, OneDrive, Intune, and related identity and endpoint services.
• Manage user and group administration, licensing, access, service health, configuration standards, retention requirements, and operational documentation within assigned authority.
• Troubleshoot service incidents and coordinate escalation through Microsoft or other cloud service providers.
• Build, maintain, document, and improve standardized computer imaging and provisioning processes for Windows endpoints and other supported devices.
• Package and deploy operating systems, applications, updates, drivers, policies, and security configurations using approved management tools.
• Coordinate device staging, quality checks, deployment, replacement, refresh, return, secure wipe, and disposition activities.
• Maintain endpoint configuration standards and ensure newly deployed devices are properly enrolled, protected, inventoried, and ready for the user.
• Maintain an accurate inventory of computers, network equipment, servers, storage, peripherals, mobile devices, software, licenses, warranties, and assigned ownership.
• Manage asset receiving, tagging, assignment, transfer, stock levels, audits, refresh planning, secure disposal, and chain-of-custody records.
• Reconcile asset records with purchasing, deployment, support, and disposal activities; investigate discrepancies and report material risks.
• Forecast infrastructure and endpoint need and provide data to support budgeting, procurement, renewal, and lifecycle decisions.
• Provide professional hands‑on user support, including desk‑side, remote, and escalation assistance for hardware, software, connectivity, identity, Microsoft 365, printing, conferencing, and access issues.
• Participate in help desk coverage during high‑volume periods, staff absences, critical incidents, deployments, and site events.
• Ensure tickets are documented, prioritized, communicated, resolved, and closed according to established service expectations.
• Create knowledge articles and coach users and IT staff on common solutions, secure practices, and effective use of technology.
• Supervise assigned employees, including setting goals, assigning work, providing coaching, and supporting ongoing professional development.
• Complete employee performance reviews and address performance concerns promptly, consistently, and in partnership with Human Resources.

Skills

TCP/IP networking

Switching

Wireless

VPN

Firewalls

DNS

DHCP

VLANs

Internet connectivity

Customer support

Project management

Tools

Windows Server

Active Directory

Microsoft Entra ID

Virtualization

Storage

Backup

Monitoring tools

Intune

Job description

Sigma, founded in 1987, is a multi‑discipline engineering and design company serving petrochemical industries. The IT Infrastructure Manager will lead the reliability and security of network, server, storage, and Microsoft 365 environments, coordinating deployments, imaging, asset management, and end-user support.

This on-site role requires hands‑on leadership and project oversight across complex IT environments.