Zero-Failure K8s Migration of 120 Microservices: 6 Pitfalls Nobody Talks About from a 3-Month Real Migration
Overview Migrating 120+ microservices from traditional VM deployments to Kubernetes sounds like a standard project: write Dockerfiles, build a cluster, migrate services, shift traffic. In planning meetings, everyone thinks three months is enough. In practice, you discover that the real challenges aren’t about “how to get services running” — that’s just helm install — but about pitfalls nobody warned you about: circular dependencies in service graphs, in-memory state loss during stateful migration, CNI performance cliffs at scale, DNS caching traps during canary traffic shifts, ConfigMap bloat, and monitoring metric gaps after migration....