This is a rare chance to join a tenured, low-turnover infrastructure team at a globally recognized, multi-billion dollar organization with a worldwide footprint and thousands of employees across multiple continents. Their on-premises environment is the backbone of global operations and this team is at the center of it all. The organization is making serious investments in modernizing their enterprise infrastructure, with hands-on AI and automation initiatives actively in flight. The technology stack here is genuinely exciting, the team culture is built on curiosity and collaboration, and your contributions will be visible from day one.

Engineers who thrive here are intellectually curious, leave ego at the door, and are energized by complexity. If you want to be challenged technically, supported in your growth, and surrounded by real professionals - this is it.

As a Senior Infrastructure Engineer, VMware vSphere/ESXi will be the heartbeat of your day-to-day work. You'll own the health, performance, and scalability of a large-scale virtualization platform while also contributing across a modern, evolving stack that includes Kubernetes, Docker, Red Hat, Ansible automation, Active Directory, and Azure IaaS. On-call rotation runs every 8 weeks, with monthly maintenance windows typically after hours or on weekends.

One thing that sets this role apart: you need to be genuinely strong in both Windows and Linux. This environment runs a large-scale mixed OS footprint, and you'll be expected to diagnose and resolve issues across both platforms with equal confidence. On the Windows side, that means Windows Server (2016+), Active Directory, Group Policy, and PowerShell. On the Linux side, you need to be comfortable at the command line including RHEL/Ubuntu, user management, permissions, disk, services, and SELinux. Candidates who are Windows-only or Linux-only will not be the right fit for this team.

VMWare & Virtualization (Primary Focus)

• Own the health, performance, and scalability of a sprawling VMware vSphere/ESXi virtualization platform — this is where you'll spend the majority of your time.
• Troubleshoot host failures, DRS/HA events, and distributed vs. standard switch configurations with confidence and speed.
• Support vMotion operations and contribute to capacity planning and platform optimization across the virtualization layer.

Containers & AI Workloads

• Get hands-on with a modern, evolving tech stack that includes Kubernetes, Docker, and Red Hat container platforms powering real AI workloads.
• Support containerized environments in production and contribute to the infrastructure underpinning active automation and AI initiatives.

Windows and Linux Systems

• Keep a large-scale Windows and Linux environment running smoothly, diagnosing everything from authentication failures and access issues to full system outages.
• Manage Windows Server (2016+) environments and support RHEL/Ubuntu systems at the command line — including user management, permissions, disk, services, and SELinux.

Automation & Configuration Management

• Build and maintain automation that actually reduces toil — writing and refining Ansible playbooks through Ansible Tower to streamline provisioning and configuration at scale.
• Leverage PowerShell scripting for task automation and operational efficiency across the Windows environment.

Identity, Access and Network Services

• Manage identity and access infrastructure including Active Directory, Group Policy, DNS, DHCP, and Certificate Services across a complex, multi-region environment.
• Maintain security and compliance through proactive vulnerability remediation, patch management, and performance monitoring.

Enterprise Tooling & Monitoring

• Use enterprise tooling including SCCM for software deployment and change management, and SCOM for infrastructure monitoring to keep the environment healthy and compliant.
• Leverage Zabbix and other monitoring platforms to maintain visibility across a large, distributed infrastructure.

Azure & Cloud Support

• Play a supporting role in Azure IaaS operations (VMs, RBAC, backup, and disaster recovery) as a complement to the core on-prem workload.

On-Call & Maintenance

• Step up during on-call windows (rotating every 8 weeks) and monthly maintenance windows to keep global operations running without interruption.
• Most changes happen after hours or on weekends - this is a global environment and uptime is non-negotiable.

REQUIRED

• 5+ years of enterprise infrastructure engineering experience, ideally in environments running thousands of servers.
• Deep, hands-on VMware vSphere/ESXi expertise; you know this platform and can troubleshoot, optimize, and scale it with confidence. This is the cornerstone of the role.
• Solid Windows Server (2016+) experience required.
• Linux (RHEL/Ubuntu) fundamentals required. You must be comfortable at the command line: navigation, user management, permissions, disk, services, and SELinux.
• Working knowledge of DRS, HA, distributed vs. standard switches, and vMotion in production environments.
• Practical experience with container technologies (Kubernetes, Docker, and Red Hat) in live production environments.
• Hands-on Ansible experience: writing and working with playbooks, not just running them.
• Strong Active Directory fundamentals across DNS, DHCP, Group Policy, and Certificate Services.
• PowerShell scripting ability and familiarity with enterprise monitoring platforms such as SCOM, Zabbix, and SCCM.
• A collaborative, professional presence - this is a tight-knit global team and communication matters.
• Adaptability and a growth mindset - this environment moves fast and rewards engineers who are curious and coachable.

Preferred:

• Cisco UCS platform experience (B-Series or C-Series) - this is a real data center environment with physical hardware.
• Hyper-V or Nutanix familiarity.
• Working understanding of Azure IaaS - enough to support and troubleshoot, not necessarily architect.
• Degree optional - what you've built and supported matters far more than where you studied.

MMD Services Inc. is an equal opportunity employer. All applicants are considered for all positions without regard to race, religion, color, sex, gender, sexual orientation, pregnancy, age, national origin, ancestry, physical/mental disability, medical condition, military/veteran status, genetic information, marital status, ethnicity, alienage or any other protected classification, in accordance with applicable federal, state, and local laws.

Pay: $115,000.00 - $135,000.00 per year

Benefits:

• 401(k)
• 401(k) matching
• Dental insurance
• Health insurance
• Life insurance
• Paid time off
• Parental leave
• Vision insurance

Work Location: Hybrid remote in Chicago, IL 60606