Migrating ingress controllers across 200+ Kubernetes clusters and 600+ service endpoints is a daunting undertaking that most organizations avoid. This talk shares real-world strategies, tools, and lessons learned from a large-scale NGINX Ingress migration at Zscaler One platform engineer team

We'll cover the complete migration lifecycle: pre-migration planning (inventory, dependency mapping, risk assessment), solution evaluation (comparing Istio, Traefik, Cilium, and cloud-native solutions), phased rollout strategies (canary deployments, traffic validation), and operational challenges (DNS TTL handling, service discovery, configuration drift detection).

You'll learn how we achieved zero-downtime migrations, reduced operational overhead, and optimized costs through careful planning and automation. Whether you're managing tens or hundreds of clusters & critical active production workloads, this talk provides a playbook for executing large-scale ingress migrations safely and efficiently