Sr. Tier III O&M Engineer

COMFORT SYSTEMS; Aurora (CO); On-site; USD 92,300 - 166,850; Full time

Job summary

COMFORT SYSTEMS is hiring a Sr. Tier III Operations and Maintenance Engineer to support various WAN and LAN networks. The successful candidate will focus on incident resolution, manage routing and firewall changes, and act as a subject-matter expert.

The candidate will be responsible for ongoing operations and maintenance, ensuring functionality across complex systems while collaborating with other teams. Attention to detail and strong technical acumen are essential.

Qualifications

• Must have a TS SCI with a Poly.
• Must comply with DoD 8570 Information Assurance Technical (IAT) Level 2.
• Demonstrated ability to read and understand technical diagrams.

Responsibilities

• Support operations and maintenance activities for WAN and LAN.
• Monitor system performance and provide incident resolution.
• Configure hardware and software for network management.

Skills

Incident resolution

Routing changes

Firewall changes

WAN technologies

LAN technologies

Boundary protection technologies

Network performance monitoring

Troubleshooting

Education

16 years of experience in a relevant field

Tools

Palo Alto

Cisco ASA

ServiceNow

MS Office (Word, Excel, PowerPoint, Visio)

Job description

Description

Leidos’ Digital Modernization Sector is seeking a Sr. Tier III operations and maintenance (O&M) engineer to support various WAN and LAN networks. The role includes incident resolution, routing changes, firewall changes, and acting as a subject‑matter expert in WAN and LAN technologies. The engineer supports the intra‑ and inter‑network and other data communications systems or segments of a networked system.

Description of Job Duties / Responsibilities

• Support operations and maintenance activities and administer networks, including LAN and WAN technologies such as OSPF, BGP, VRFs, VLANs, VRRP, MPLS.
• Monitor the performance of systems and networks.
• Configure, test, and maintain hardware, networking software, and operating system software.
• Review user requests for upgrades or additions to the network, assess impact on performance, and provide advice and guidance on the most practical technical approach.
• Perform long‑term O&M activities, including tier 3 troubleshooting and problem resolution.
• Prepare troubleshooting procedures for restoring the network to optimal performance levels.
• Provide fault management for the network and support performance management functions.
• Respond to, isolate, and resolve network troubles.
• Execute reporting functions and data input associated with network management.
• Coordinate with configuration management and implementation teams.
• Analyze network characteristics (e.g., traffic, connection time, transmission speeds, packet sizes, throughput); recommend procurement, removal, and modifications to network components.
• Optimize network topologies and site configurations.
• Coordinate requirements with users.
• Assess and document current site network configuration and user requirements.
• Maintain operating systems, communications software, database packages, compilers, assemblers, and utility programs.
• Apply software, hardware, and standards IT skills in the analysis, specification, development, integration, and acquisition of open systems for information management applications.
• Ensure these systems and applications comply with open‑systems architecture references and standards such as the IEEE Open Systems Environment (OSE) reference model.
• May have up to 10% COMSEC responsibilities, as needed.
• Subject to being called in during afterhours for incident resolution.

Requirements

• TS SCI with a Poly.
• Candidate must have 16 years of experience that can be a combination of work history and education (e.g., Doctorate + 8 years, Master’s + 10 years, Bachelor’s + 12 years, Associate’s + 14 years, HS diploma + 16 years).
• Must comply with DoD 8570 Information Assurance Technical (IAT) Level 2.
• Experience configuring and troubleshooting boundary protection technologies such as Palo Alto, Cisco ASA, and Forcepoint appliances.
• Experience configuring and troubleshooting Juniper and Cisco routers and switches.
• Experience with protocols such as OSPF, BGP, VPNs, VRFs, MPLS.
• Working knowledge of boundary protection best practices.
• Understanding of routing, switching, IP subnetting, NAT, and security technologies.
• Demonstrated ability to engineer and modify rulesets to allow connectivity for new customer requirements.
• Demonstrated ability to read, understand, and develop schematic diagrams, technical manuals, and documentation such that the supported equipment and software can be maintained with minimal training.
• Working knowledge of ServiceNow or a similar IT Service Management product.
• Superior verbal and written communication skills.
• Intermediate knowledge of MS Office products Word, Excel, PowerPoint, and Visio.

Pay Range

Pay Range $92,300.00 – $166,850.00.

The Leidos pay range for this job level is a general guideline only and is not a guarantee of compensation. Additional factors considered in extending an offer include responsibilities of the job, education, experience, knowledge, skills, and abilities, internal equity, market data, applicable bargaining agreement, and other applicable factors.

Commitment to Non-Discrimination

All qualified applicants will receive consideration for employment without regard to sex, race, ethnicity, age, national origin, citizenship, religion, physical or mental disability, medical condition, genetic information, pregnancy, family structure, marital status, ancestry, domestic partner status, sexual orientation, gender identity or expression, veteran or military status, or any other basis prohibited by law. Leidos will also consider qualified applicants with criminal histories consistent with relevant laws.

REQNUMBER

R-00183671