We are using Elasticsearch in a Kubernetes cluster (not exposed publicly) without X-Pack security, and had it working in 5.x with elastic/changeme, but after trying to get it set up with 6.x, it's now requiring a password, and the default of elastic/changeme no longer works.
We didn't explicitly configure it to require authentication, since it's not publicly exposed and only accessible internally, so not sure why it's requiring the password, or more importantly, how we can find out what it is or how to set/change it without using X-Pack security.
Will we end up needing to subscribe to X-Pack since we're trying to us it within a Kubernetes cluster?
If you don't use XPack at all you should use oss flavor of Elasticsearch. It includes only open source components of Elasticsearch:
docker pull docker.elastic.co/elasticsearch/elasticsearch-oss:6.4.2The interesting thins is, Elastic have removed any mention of it in documentation since 6.3.
See:
Not sure how you are deploying Elasticseach in Kubernetes but we had a similar issue an ended passing this:
xpack.security.enabled=falsethrough the environment to the container.