Added note for ingress annotation

examples/tomcat-security/README.md

@@ -9,6 +9,15 @@ There are 3 scenarios for configuring the security of the GraphDB instance:
 **Note:**
 If the Tomcat server is configured with SSL/TLS it will also configure the cluster gRPC communication SSL/TLS.
 
+**Ingress**  
+If you are using the default nginx ingress controller, you must include the following annotation to ensure proper 
+communication between the ingress and the backend:  
+```yaml
+ingress:
+  annotations:
+    nginx.ingress.kubernetes.io/backend-protocol: "HTTPS"
+```
+
 ### See more about Tomcat TLS/SSL set up:
 - GraphDB official documentation: https://graphdb.ontotext.com/documentation/10.8/encryption.html#configuring-graphdb-instance-with-ssl
 - Tomcat documentation: https://tomcat.apache.org/tomcat-9.0-doc/ssl-howto.html