Senior Network Security Engineer

GovCIO is seeking a highly experienced Senior Network & Security Engineer to lead the design, operation, troubleshooting, and continuous improvement of enterprise network-security infrastructure. This role is responsible for Palo Alto Networks next-generation firewalls, Panorama, High Availability, Cisco switching, network segmentation, Cortex XSIAM, and Strata Logging Service. The Senior Engineer will serve as a technical escalation point for complex network and security incidents, lead architecture and implementation initiatives, establish standards, and partner with SOC, infrastructure, cloud, application, and leadership teams to reduce risk and maintain highly available services. This position will be located within the United States and will be a fully remote opportunity. Responsibilities The successful Senior Network & Security Engineer will be a hands-on technical leader with deep expertise in Palo Alto Networks firewalls, Panorama, HA, and Cisco enterprise networking. This person will lead firewall-policy and microsegmentation design, troubleshoot complex TCP/IP and packet-flow issues, ensure resilient HA operations, and integrate security telemetry with Cortex XSIAM and Strata Logging Service. The candidate must be able to independently lead technical projects, resolve high-impact incidents, improve security controls, and mentor other engineering team members. Lead the design, deployment, administration, and lifecycle management of Palo Alto Networks NGFW environments running PAN-OS. Own centralized firewall management through Palo Alto Panorama, including device groups, templates, template stacks, policy inheritance, upgrades, configuration backups, log monitoring, and firewall onboarding. Design and govern security policies using zero-trust, least-privilege, application-aware, and risk-based principles. Configure and troubleshoot security zones, NAT, virtual routers, static and dynamic routing, IPsec VPN, GlobalProtect, decryption, URL Filtering, Threat Prevention, WildFire, DNS Security, and App-ID policies. Lead enterprise network-segmentation and microsegmentation initiatives using security zones, VLANs, subinterfaces, virtual routers, routing controls, and application-based security policies. Develop secure controls for traffic between users, servers, applications, management networks, guest networks, IoT/OT devices, data-center workloads, and cloud resources. Architect, configure, test, and troubleshoot Palo Alto High Availability deployments, including Active/Passive and Active/Active designs as required. Resolve complex HA failures involving HA1 control links, HA2 session/state synchronization, HA3 packet forwarding, peer communications, configuration synchronization, monitoring failures, split-brain prevention, and failover recovery. Plan and execute HA failover testing, PAN-OS upgrades, disaster-recovery exercises, and maintenance procedures while minimizing service impact. Troubleshoot HA infrastructure dependencies, including cables, transceivers, switch ports, port channels, VLANs, routing, MTU, latency, packet loss, and redundant-path failures. Lead the configuration, support, and troubleshooting of Cisco Catalyst and Nexus switching environments. Design and support VLANs, trunking, STP/RSTP/MST, EtherChannel/port channels, HSRP/VRRP, Layer 2/Layer 3 switching, ACLs, QoS, switch security, routing, and access-control technologies. Diagnoses complex connectivity and performance issues through firewall logs, session inspection, packet captures, CLI diagnostics, switch counters, flow data, and network-monitoring platforms. Analyze TCP/IP behavior, including handshake failures, SYN/SYN-ACK/ACK flow, retransmissions, resets, timeouts, asymmetric routing, MTU/MSS issues, fragmentation, latency, packet loss, and NAT translation problems. Verify packet flow across firewall policy, App-ID, routing, NAT, decryption, threat prevention, VPN, switching, and server/application layers. Monitor firewall management-plane and dataplane health, including CPU, memory, session capacity, packet buffers, throughput, logging, and interface performance. Integrate Palo Alto NGFWs and Panorama with Strata Logging Service and Cortex XSIAM. Ensure reliable firewall log forwarding, cloud logging, log ingestion, data normalization, event availability, retention, and telemetry quality. Use Cortex XSIAM and XQL Search to investigate, correlate, and respond to firewall, endpoint, identity, cloud, and third-party security events. Partner with SOC teams to tune detections, investigate alerts, develop response procedures, improve visibility, and support incident containment and remediation. Lead root-cause analyses for major network or security incidents and deliver corrective and preventive action plans. Develop and maintain network diagrams, firewall-policy documentation, HA designs, runbooks, change plans, architecture standards, and operational procedures. Mentor junior engineers and provide technical leadership during projects, production incidents, and security reviews. Qualifications Bachelor’s degree with 8+ years (or commensurate experience) 7+ years of progressive experience in network engineering, network security, firewall administration, or security infrastructure operations. 5+ years of hands-on Palo Alto Networks firewall experience in a production enterprise environment. Advanced operational experience with Palo Alto Panorama, including multi-device policy management, templates, device groups, upgrades, configuration management, and troubleshooting. Strong hands-on experience designing, maintaining, and troubleshooting Palo Alto High Availability environments. Advanced understanding of HA1, HA2, HA3, configuration synchronization, session synchronization, failover behavior, link monitoring, path monitoring, peer health, and recovery processes. Strong expertise in TCP/IP, IPv4/IPv6, DNS, DHCP, ARP, routing, NAT, VPNs, and packet-level troubleshooting. Demonstrated ability to investigate TCP handshakes, resets, retransmissions, MTU/MSS issues, asymmetric routing, connection timeouts, and firewall session behavior. Extensive experience with Cisco Catalyst and/or Nexus switching technologies. Strong knowledge of enterprise switching and routing, including VLANs, trunking, STP/RSTP/MST, EtherChannel, HSRP/VRRP, routing protocols, ACLs, QoS, and switch-security controls. Proven experience designing or implementing network segmentation and microsegmentation solutions. Working knowledge of Cortex XSIAM, Strata Logging Service, security-event correlation, alert investigation, XQL Search, and firewall log ingestion. Ability to lead technical design discussions, independently manage complex workstreams, and communicate risks and recommendations to technical and nontechnical stakeholders. Strong documentation, change-management, incident-management, and root-cause-analysis skills. Clearance Required: Must be able to attain and maintain AOUSC Public Trust Preferred Skills and Education Master’s degree in Cybersecurity, Information Technology, Computer Science, Engineering, or a related field preferred Palo Alto Networks certifications: PCNSA, PCNSE, PCCSE, or equivalent enterprise-level experience. Cisco certifications: CCNP Enterprise, CCNP Security, CCIE Enterprise Infrastructure, CCIE Security, or comparable expertise. Experience with Palo Alto Prisma Access, Prisma Cloud, Cortex XDR, Cortex XSOAR, or cloud-delivered security services. Experience with Cortex XSIAM alert triage, XQL queries, data-source integrations, detection tuning, dashboards, reporting, and response automation. Experience with Cisco ISE, Cisco ACI, SD-Access, or enterprise network-access-control solutions. Familiarity with Fortinet Security Fabric, FortiGate, FortiManager, and FortiAnalyzer. Experience with AWS, Azure, Google Cloud Platform, hybrid-cloud network design, and cloud-security controls. Familiarity with SIEM, SOAR, EDR/XDR, vulnerability-management, NDR, network-monitoring, and ticketing platforms. Automation skills using Python, Ansible, Terraform, REST APIs, or related infrastructure-as-code and orchestration tools. Experience supporting 24x7 environments, participating in an on-call rotation, leading critical incidents, and executing emergency changes. Posted Salary Range USD $120,000.00 - USD $140,000.00 /Yr. Govcio LLC