Sure. But it does not mean that another old process is not trying to connect to this instance.
Let me sum up the situation so I understand the full picture.
You have one elasticsearch instance, running on docker, which is totally empty as you remove data dir before starting.
You start it. Then GET _cat/indices is totally empty?
Then you start Kibana 5.2.2 instance and it prints in your logs the message you pasted before. Is that right?
Then you start a Logstash 5.2.2 instance and it also prints similar log line. Still right?
Are Kibana and Logstash totally fresh new downloads from our website? Or did you upgrade them somehow?