Network Engineer II

Join us in bringing joy to customer experience. Five9 is a leading provider of cloud contact center software, bringing the power of cloud innovation to customers worldwide. Living our values everyday results in our team-first culture and enables us to innovate, grow, and thrive while enjoying the journey together. We celebrate diversity and foster an inclusive environment, empowering our employees to be their authentic selves. To complement our rapid growth, we are sourcing a Network Engineer II to operate in a 24/7 Software-as-a-Service (SaaS) environment, taking ownership of complex LAN infrastructure initiatives and driving operational excellence across Cisco Nexus, Palo Alto, and F5 platforms. You will lead projects, own end-to-end troubleshooting, drive automation strategy, and provide technical leadership during incidents — while mentoring junior engineers and representing the network domain to senior stakeholders. Troubleshooting & Incident Response Own end-to-end troubleshooting of complex LAN connectivity, firewall policy, and load balancer issues, and drive resolution with customers and internal teams. Conduct in-depth analysis of network incidents, identify root causes, and implement preventive measures to reduce repeat occurrences. Lead and coordinate responses to network and security incidents, ensuring timely resolution and minimizing potential impacts. Participate in on-call rotation following the Sun Model schedule; provide technical leadership during outages and lead post-incident root cause analysis and corrective action planning. Lead the review, analysis, and execution of network change requests within the data-center fabric domain, ensuring adherence to change management and risk-mitigation standards. Projects & Architecture Lead and drive LAN infrastructure projects involving Cisco Nexus switching, Palo Alto firewalls, F5 load balancers, and NDFC fabric management . Partner with cross-functional stakeholders to design and deliver next-generation data-center fabric architectures, leveraging VXLAN, Cisco Nexus Dashboard, Kubernetes networking (Calico), and AI/ML-enabled networking . Manage and operate data-center fabric services across hybrid and multi-cloud environments — on-premises Cisco Nexus infrastructure, GCP, and AWS . Perform traffic engineering and capacity planning to guide long-term infrastructure investments. Develop and maintain technical roadmaps, architecture standards, and configuration policies for LAN, firewall, and load balancer environments. Manage and maintain existing network infrastructure (Nexus, Palo Alto, F5), ensuring reliability, performance, and equipment lifecycle planning. Monitoring & Observability Develop and report operational and performance metrics using observability platforms including Prometheus, Grafana, and SolarWinds . Define, measure, and report site reliability using SLI/SLO Maintain operational focus on the data-center fabric while coordinating cross-team efforts with network security and load balancing functions to ensure end-to-end service reliability. Analyze historical network incidents to identify systemic issues and inform preventive engineering. Automation Drive automation strategy and execution using Ansible, Terraform, Python, and CI/CD pipelines for provisioning, configuration, and monitoring. Implement automated remediation to prevent recurrence of known issues. Demonstrate and scale a culture of automation across engineering and operations teams. Track and manage projects, processes, and technology initiatives across the team, ensuring alignment, visibility, and timely execution. Maintain runbooks, topology diagrams, and SOPs. Security Manage overall network security including routing policies, Palo Alto firewall rules, and access controls to protect infrastructure. Own all operational aspects of network security infrastructure — OS maintenance, vulnerability management, capacity planning, lifecycle management, and certificate administration. Requirements Bachelor's degree in computer science or a related technical field preferred, or equivalent practical experience. Minimum 5–10 years of experience in medium-to-large networks, IP routing, switching, and security principles in a production SaaS or enterprise environment, including experience as a technical subject matter expert. Deep hands-on expertise with Palo Alto firewalls — security policy design, Panorama management, Global Protect VPN, and threat prevention. Advanced experience with F5 BIG-IP — LTM, GTM, iRules, SSL offloading, and application delivery configurations. Expert-level knowledge of Cisco Nexus 9k/7k/5k/2k, NX-OS, and NDFC , including VXLAN/EVPN fabric deployments. Extensive hands-on experience with software-defined networking (SDN) — OpenStack Neutron and Calico (Kubernetes) . Hands-on skills with Cisco IOS required; Nexus OS and NDFC expertise required. Proven experience automating infrastructure processes and deployments using Ansible, Terraform, Python, and CI/CD pipelines , with demonstrated ability to drive and scale a culture of automation. Demonstrated expertise in LAN protocols and technologies — VXLAN, EVPN, OSPF, BGP, MPLS, and STP/RSTP — with strong hands-on experience with dynamic routing protocols, particularly BGP in data-center fabric environments. Experience implementing solutions involving large data centers, inter-business routing plans, site-to-site IPSec VPNs, firewalls, and MPLS VPNs. Strong experience with network monitoring and observability tools — SolarWinds, Prometheus, Grafana, NetFlow, SNMP, and packet brokers. Demonstrated experience with incident response, root cause analysis, change management, and operational governance; experience defining, measuring, and reporting reliability using SLI/SLO metrics. Knowledge of Linux network functions and SaaS/cloud-based environments. Knowledge of AWS and GCP cloud platforms, including cloud networking concepts such as VPCs, security groups, transit gateways, and cloud-based load balancing. Proven ability to mentor engineers, lead technical projects independently, and manage multiple initiatives in parallel, with demonstrated project management skills. Excellent communication skills, both oral and written; ability to clearly represent technical domains and team outcomes to senior leadership and non-technical stakeholders. Nice to Have Telecommunications technologies — VoIP, RTP, SIP peering/trunking, and SBC. Work Location: This role is fully remote for candidates who reside outside the 30 mile radius of one of our offices. For candidates who reside within a 30 mile radius of one of our offices, this role is Hybrid and would require 3 days a week (T, W, TH) in office. As part of our continued commitment to diversity, equity, and inclusion, Five9 supports pay transparency during the entire recruitment process. Actual compensation packages are based on several factors that are unique to each candidate including, but not limited to: skill set, depth of experience, certifications, and specific work location. The range displayed reflects the minimum and maximum target for new hire salaries for the job across the United States. Your recruiter can share more about the specific compensation package during your hiring process. Additionally, the total compensation package for this position may also include an annual performance bonus, stock, and/or other applicable incentive compensation plans. Our total reward package also includes: Health, dental, and vision coverage, beginning on the first day of employment. Five9 covers 100% of the employee portion of the health, dental and vision coverage and shares a high portion of the dependent cost. We also offer Short & Long-Term Disability, Basic Life Insurance, and a 401k saving plan with employer matching. Access to an innovative mental health support platform that offers personalized care and resources in areas such as: therapy, coaching and self-guided mindfulness exercises for all covered employees and their covered dependents. Generous employee stock purchase plan. Paid Time Off, Company paid holidays, paid volunteer hours and 12 weeks paid parental leave. All compensation and benefits are subject to the requirements and restrictions set forth in the applicable plan documents and any written agreements between the parties. The US base salary range for this role is below. $82,600 — $230,800 USD Five9 embraces diversity and is committed to building a team that represents a variety of backgrounds, perspectives, and skills. The more inclusive we are, the better we are. Five9 is an equal opportunity employer. Note: Five9 will never request that an applicant send money as a prerequisite for commencing employment with Five9.