As announced November 2025, Kubernetes will retire Ingress-NGINX in March 2026. Despite its widespread usage, Ingress-NGINX is full of surprising defaults and side effects that are probably present in your cluster today. This blog highlights these behaviors so that you can migrate away safely and make a conscious decision about which behaviors to keep. This post also compares Ingress-NGINX with Gateway API and shows you how to preserve Ingress-NGINX behavior in Gateway API. The recurring risk pattern in every section is the same: a seemingly correct translation can still cause outages if it does not consider Ingress-NGINX's quirks.