Updated S3 Nginx Proxy (markdown)

S3-Nginx-Proxy.md

@@ -156,4 +156,21 @@ server {
 	ssl on;
 	ssl_certificate /{path_to_ssl_cert}/cert.pem;
 	ssl_certificate_key /{path_to_ssl_cert}/key.pem;
-}
+}
+
+## Kubernetes Ingress
+
+When using Kubernetes Ingress (nginx-ingress controller), you must disable request buffering to prevent signature verification failures on write operations (PUT, POST). Without this setting, nginx removes the `Transfer-Encoding: chunked` header that S3 clients include in their signature, causing 403 Forbidden errors on uploads while reads work fine.
+
+**Required Helm chart configuration:**
+
+```yaml
+s3:
+  ingress:
+    enabled: true
+    className: nginx
+    host: s3.example.com
+    annotations:
+      nginx.ingress.kubernetes.io/proxy-request-buffering: "off"
+      nginx.ingress.kubernetes.io/proxy-body-size: "0"
+```