Senior Network Security Engineer

GovCIO LLC is seeking a Senior Network & Security Engineer to lead enterprise network security infrastructure design, operations, troubleshooting, and continuous improvement.

• Design, deploy, administer, and manage the lifecycle of Palo Alto Networks NGFW environments running PAN-OS
  .
• Own centralized firewall management with 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
  , Global Protect
  , decryption,
  URL Filtering
  , Threat Prevention
  , Wild Fire
  , DNS Security
  , and App- policies.
• Lead enterprise network segmentation and microsegmentation using security zones, VLANs, subinterfaces, virtual routers, routing controls, and application-based security policies.
• Develop secure controls for traffic across 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.
• Resolve complex HA failures across HA1 control links, HA2 session and 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 configuration support and troubleshooting of Cisco Catalyst and Nexus switching environments.
• Design and support VLANs, trunking,
  STP/RSTP/MST
  , Ether Channel/port channels
  , HSRP/VRRP
  , Layer 2/Layer 3 switching, ACLs, QoS, switch security, routing, and access-control technologies.
• Diagnose complex connectivity and performance issues using 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 flows, retransmissions, resets, timeouts, asymmetric routing, MTU/MSS issues, fragmentation, latency, packet loss, and NAT translation problems.
• Verify packet flow end-to-end across firewall policy, App-, 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 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…