Sr. RHEL Systems Engineer, OT/SCADA

ON.energy • Houston, TX

3d • Hybrid

About The Position

ON.energy is building the power infrastructure that makes the AI era possible. As AI demand surges past what the grid and traditional data centers can support, ON.energy provides a new class of power technology proven at gigawatt scale and trusted by the world’s leading cloud and AI companies. Our systems are already deployed across 2.5 GW of hyper-scale campuses, validated by top U.S. national labs, and certified for grid-safe operation by major utilities. With real products in the field, we’re scaling faster than the grid can, transforming power from a bottleneck into a competitive advantage for the companies building the future. The Senior RHEL engineer will own the OS and container platform behind our on-premises energy-management deployments. You’ll build and harden the tailored RHEL image and the containerized Ignition SCADA workload running on industrial PCs across U.S. data-center sites, and act as our deep RHEL authority and L3 escalation point. This is a platform-engineering and expertise role — not field installation. You will own our OS architectures, container builds and configuration, and the runtime that hosts Ignition, while the SCADA team owns everything configured inside Ignition (tags, screens, logic). On the network side, the host firewall and OS-level networking (interfaces, routing, DNS, firewalld/nftables) are yours, while the physical and site network beyond the host NIC belongs to Operational Technology (OT). Travel to third-party data-center sites is for troubleshooting and support only. The separate OT team commissions and deploys every machine, so you won’t install systems in the field.

Requirements

• 7+ years of senior, hands-on production RHEL/Linux engineering.
• Container-native delivery: Podman, quadlets/systemd, building and owning container images (including packaging a JVM-based app such as Ignition), and registry management.
• Reproducible, turnkey, versioned RHEL image building (bootc, Kickstart, Image Builder/osbuild, or Ansible-driven).
• OS and image hardening to a recognized baseline (CIS/STIG).
• Patch and lifecycle management for restricted/disconnected environments, including offline/mirrored content and registries.
• Automation (Ansible) and version control.
• Strong Linux networking and diagnostics: firewall administration (firewalld/nftables) and packet/connectivity tooling (Wireshark, tcpdump, ss, ip), plus containerized debug environments (toolbox).
• Confidence operating as the RHEL authority, with strong documentation habits.

Nice To Haves

• OT/ICS or SCADA exposure and frameworks (IEC 62443, NERC CIP, NIST 800-82).
• Familiarity with Ignition specifically.
• Windows image automation (Packer) and Windows patching/hardening familiarity.
• RHCSA / RHCE / RHCA certifications.

Responsibilities

• Build, version, and maintain a reproducible, turnkey RHEL image tailored to the SCADA host’s needs (time sync, firewall/ports, storage, service ordering, resource tuning).
• Own the SCADA container image end to end: Containerfile, base image, JVM, persistence, ports, hardening, scanning, and registry.
• Run containers as systemd services via Podman and quadlets.
• Harden the OS and images to a recognized baseline (CIS/STIG) and define a patching and lifecycle strategy for OT uptime and restricted/disconnected sites (offline/mirrored registry).
• Troubleshoot full-stack — OS, container runtime, and application runtime behavior — remotely and on-site, handing off application-level issues to the SCADA team.
• Own host-level networking and firewall configuration (interfaces, routing, DNS, firewalld/nftables, and port exposure for the SCADA container), and lead connectivity troubleshooting between the host and site infrastructure.
• Document runbooks for the OT team and help define the connectivity and security posture.
• Maintain the Windows image pipeline (Packer-based) in steady state once established: periodic patching, hardening updates, and image rebuilds.

Benefits

• Competitive salary + annual performance-based bonus eligibility
• Medical, dental, and vision insurance
• 401(k) with company match
• Paid time off and company holidays
• Christmas Bonus (Aguinaldo): 30 days
• Major medical expenses and life insurance
• Paid time off and holidays (per local policy)
• Professional development and growth opportunities
• Opportunity to grow with a mission-driven team shaping the future of clean energy

What This Job Offers

• Job Type: Full-time
• Career Level: Senior
• Education Level: No Education Listed