Websocket Error on Kubernetes

Troubleshooting
5

I was able to resolve the issue with the help of some mattermost developers.
The main issue was the nginx ingress controller.

I think nginx.ingress.kubernetes.io annotation is for GitHub - kubernetes/ingress-nginx: Ingress-NGINX Controller for Kubernetes and the link you sent is GitHub - nginxinc/kubernetes-ingress: NGINX and NGINX Plus Ingress Controllers for Kubernetes which according to docs uses nginx.org annotation. I have no experience with the latter so it is hard for me to say if it is configured properly. (Comment on the github issue)

After installing the “standard” nginx controller (kubernetes/ingress-nginx), everything is working as expected.