I have a websocket .net application inside K8s cluster. I need to implement sticky session for the websocket using the nginx opensource.
I have read the documentation of nginx and kubernetes. https://github.com/kubernetes/ingress-nginx/blob/master/docs/user-guide/nginx-configuration/annotations.md#session-affinity
It says we can use below configuration for sticky session:
nginx.ingress.kubernetes.io/affinity: "cookie"
nginx.ingress.kubernetes.io/session-cookie-name: "ingresscoookie"
nginx.ingress.kubernetes.io/session-cookie-hash: "sha1"
nginx.ingress.kubernetes.io/session-cookie-expires: "172800"
nginx.ingress.kubernetes.io/session-cookie-max-age: "172800
but this doesnot seem to work. I have tried the example code provided by kubernetes here https://github.com/kubernetes/ingress-nginx/blob/master/docs/examples/affinity/cookie/ingress.yaml.
This works for me, so I believe cookie based session affinity does not seem to work for websockets.
On further digging the documentation it says that I can use IP hashing algorithm. so I tried using below annotation.
nginx.ingress.kubernetes.io/upstream-hash-by: "$remote_addr"
this also failed. The requests are still balanced using the default algorithm.
How can I achieve session persistence?