Senior Network Engineer

Marathon Petroleum; Texas City (TX); On-site; USD 120,000 - 150,000; Full time

Job summary

Marathon Petroleum is seeking a Senior Business LAN Network Engineer to lead the design, implementation, and lifecycle management of refinery LAN infrastructure across complex industrial sites. You will focus on Layer 1 physicals, Layer 2 switching, and practical Layer 3 integration while collaborating with site IT, cybersecurity, facilities, vendors, and business stakeholders.

You will mentor engineers, strengthen LAN standards, improve documentation, and drive reliability, deployment speed,

Qualifications

• Experience leading LAN infrastructure design and deployment.
• Strong knowledge of Layer 1 physical infrastructure, Layer 2 switching, and Layer 3 integration.
• Ability to mentor engineers and drive reliability improvements.

Responsibilities

• Lead architecture, design, implementation, and lifecycle management of refinery LAN infrastructure.
• Develop and maintain LAN standards, reference designs, cabling, labeling, and resiliency patterns.
• Serve as senior escalation point for complex LAN issues affecting refinery operations.
• Troubleshoot Layer 1/Layer 2 cabling, fiber, patching, VLANs, and switch stacks.
• Support Layer 3 integration with routed uplinks, DHCP relay, gateways, and firewall interfaces.
• Lead LAN refreshes, lifecycle replacements, and expansion projects; coordinate with various stakeholders.

Skills

LAN architecture

Layer 1/2 expertise

Layer 3 routing

Network troubleshooting

Documentation

Mentoring

Job description

An exciting career awaits you

At MPC, we're committed to being a great place to work - one that welcomes new ideas, encourages diverse perspectives, develops our people, and fosters a collaborative team environment.

Position Summary

Join Marathon Petroleum as a Senior Business LAN Network Engineer and help shape the secure, reliable network infrastructure that keeps our refinery business operations connected and moving forward. In this highly visible role, you will lead the design, architecture, implementation, lifecycle management, and advanced support of business LAN environments across complex industrial sites, with strong emphasis on Layer 1 physical infrastructure, Layer 2 switching services, and practical Layer 3 integration. You will work on meaningful infrastructure challenges that directly support safe, reliable refinery operations while partnering with site IT, enterprise network engineering, cybersecurity, facilities, telecom providers, contractors, vendors, and business stakeholders. This opportunity is ideal for a hands‑on technical leader who wants to make a measurable impact in a collaborative, safety‑focused organization that values integrity, inclusion, continuous improvement, and excellence. The successful candidate will influence LAN strategy and standards, strengthen resiliency, improve documentation and troubleshooting practices, mentor engineers, and drive outcomes in reliability, deployment speed, cost optimization, and operational risk reduction. If you enjoy solving complex problems, leading through influence, and building infrastructure that supports critical energy operations, this role offers the opportunity to contribute, grow, and make a difference at Marathon Petroleum.

Key Responsibilities

• Lead the architecture, design, implementation, and lifecycle management of refinery business LAN infrastructure, including switching, structured cabling, fiber, network closets, telecom spaces, and related Layer 1 and Layer 2 components.
• Develop and maintain LAN standards, reference designs, configuration baselines, cabling and labeling practices, resiliency patterns, and site implementation guidance.
• Serve as a senior escalation point for complex LAN incidents, recurring reliability issues, performance concerns, design gaps, and high-impact outages affecting refinery business operations.
• Troubleshoot and resolve Layer 1 and Layer 2 issues involving cabling, fiber, optics, patching, switch stacks, VLANs, trunks, spanning tree, link aggregation, port security, and access-layer performance.
• Support Layer 3 integration with routed uplinks, gateways, subnet coordination, DHCP relay, firewall interfaces, wireless connectivity, and enterprise routing handoffs.
• Lead LAN refreshes, lifecycle replacements, business expansion projects, construction support, office moves, turnaround planning, and remediation of aging infrastructure.
• Partner with cybersecurity teams to strengthen segmentation, secure switch management, NAC or 802.1X readiness, logging, vulnerability remediation, and configuration compliance.
• Maintain accurate technical documentation, including logical and physical diagrams, switchport records, patch panel mappings, fiber routes, VLAN assignments, inventories, rack elevations, and design decisions.
• Coordinate changes with refinery operations, facilities, vendors, contractors, telecom providers, cybersecurity, enterprise network teams, and business stakeholders to minimize operational disruption.
• Set monitoring thresholds, analyze traffic and utilisation trends, tune performance, identify root causes, and proactively reduce recurring network issues.
• Evaluate network hardware, platforms, tools, and emerging technologies to improve reliability, scalability, security, and operational efficiency.
• Provide technical leadership, mentoring, peer review, and guidance to engineers, site IT staff, contractors, and project teams while reinforcing safety, change control, cybersecurity, and operational risk management practices.
• Deploys complex network configurations for on‑premise or cloud‑based networks and assists in the development of playbooks for network systems.
• Assists in the integration of new systems and tools. Develops and maintains scripts to facilitate network administrative tasks and automate repetitive processes.
• Sets the requirements and thresholds for monitoring systems for network devices. Participates in troubleshooting sessions for network‑related issues at all layers of the OSI model.
• Monitors performance, identifies areas for improvement for the network and implements performance tuning.
• Identifies trends in issues and determines the root cause to reduce future issues.
• Adheres to network policies, standards, and standard operating procedures for how‑to documents.
• Undertakes the regular analysis and interpretation of traffic and utilisation of services on network connections.
• Observes systems for network alerts and events so quick response can be provided and issues can be proa