By default, Elasticsearch runs inside the Docker container as the user elasticsearch, with both a UID and GID of 1000. Therefore, we must ensure that the data directory (/usr/share/elasticsearch/data) and all its content is going to be owned by this the elasticsearch user so that Elasticsearch can write to them.
When Kubernetes bind-mounted the PersistentVolume to our /usr/share/elasticsearch/data, it was done using the root user. This means that the /usr/share/elasticsearch/data directory is no longer owned by the elasticsearch user.
Therefore, to complete our deployment of Elasticsearch, we need to use an Init Container to fix our permissions. This can be done by running chown -R 1000:1000 ...
