Non writable elasticsearch.keystore path - Elasticsearch 6.8

Hi

I am trying to create a custom docker container and use it in a Kubernetes cluster. I would like my build and deployment scripts to create custom Elasticsearch configuration file and mount them into the docker container. This would be easy enough to do but for the fact that Elasticsearch writes into the folder where its configuration file are stored. In particular it tries to write elasticsearch.keystore in the folder with other configuration files (such as elasticsearch.yml) are stored. However this mounted volume is read only , which causes the problem.

I specifically need Elasticsearch 6.8.

I am unable to find any configuration option that can change the location of elasticsearch.keystore and separate it from the rest of the files under $ES_PATH_CONF.

Is there such an option ?

If there is no such option what are my other alternatives ?

Aren't files that are modified at run time supposed to be put in "/var/lib" ? If so why this unusual location for "elasticsearch.keystore" ?

regards