Blog
Kubernetes Ingress-NGINX: CORS annotations, snippets, and controller upgrades
nginx.ingress.kubernetes.io/cors-* annotations generate config; validate rendered nginx after each controller bump.
1 min read
kubernetesingressnginxcors
Multi-tenant clusters
Namespace-scoped Ingresses can conflict if two teams reflect different origins for the same host—use distinct hosts.
NetworkPolicies do not replace CORS; they filter L4/L3 but browsers still enforce JS rules.
Observability
Ingress access logs should include Origin for debugging cross-team incidents.
Pair with Prometheus alerts on 499 client cancellations during preflight storms.