Senior VMware NSX Engineer

**ACTIVE TS/SCI SECURITY CLEARANCE REQUIRED** We are seeking an experienced Senior NSX Engineer to design, implement, operate, secure, and troubleshoot VMware NSX-based network virtualization solutions supporting a mission-critical U.S. Department of War environment. Candidates must possess an active Top Secret/SCI (TS/SCI) security clearance with a current CI Polygraph. The ideal candidate brings 5+ years of hands-on VMware NSX engineering experience, strong VMware vSphere and VMware Cloud Foundation (VCF) integration knowledge, and the ability to own the full NSX lifecycle from architecture and deployment through security hardening, automation, upgrades, and Tier 3 incident resolution. Key Responsibilities Design, deploy, configure, operate, and sustain VMware NSX-T / VMware Cloud Foundation Networking across production, development, test, and mission environments. Engineer NSX Manager clusters, transport nodes/profiles, transport zones, uplink profiles, VDS/N-VDS networking, and NSX Edge clusters. Design and administer overlay and VLAN-backed segments, Tier-0/Tier-1 gateways, distributed routing, BGP, static routing, ECMP, route redistribution, and north-south/east-west connectivity. Implement microsegmentation and Zero Trust-aligned controls using Distributed Firewall, Gateway Firewall, security groups, dynamic membership, tags, context profiles, and policy-based security. Develop auditable, least-privilege firewall policies in coordination with cybersecurity, ISSO/ISSM, RMF, application, and network teams Integrate NSX with vCenter, vSphere, VCF, vSAN, VMware Aria Operations/Logs, PKI, identity, SIEM, vulnerability-management, and enterprise monitoring platforms Troubleshoot BGP/routing adjacency failures, MTU/TEP/Geneve issues, asymmetric routing, firewall processing, packet loss, performance degradation, and NSX Edge failures Perform packet-level analysis using NSX CLI/nsxcli, vmkping, pktcap-uw, tcpdump-uw, Traceflow, flow monitoring, and distributed firewall analysis Lead NSX upgrades, patching, certificate replacement, migrations, backup/recovery validation, and lifecycle-management activities with formal implementation, test, validation, and backout plans. Maintain engineering standards, configuration baselines, diagrams, firewall matrices, runbooks, and as-built documentation; provide Tier 3 escalation support and mentor junior engineers. Required Qualifications Active Top Secret/SCI (TS/SCI) security clearance with current CI Polygraph Bachelor's degree in Information Technology, Computer Science, Engineering, Cybersecurity, or a related discipline; equivalent relevant experience may be substitute 5+ years of hands-on VMware NSX experience in enterprise-scale environments and 5+ years of VMware vSphere experience, including ESXi, vCenter Server, VDS, virtual networking, cluster operations, and troubleshooting Advanced NSX-T / VCF Networking expertise: overlay/VLAN segments, Tier-0/Tier-1 gateways,…