Persist data from docker container to host machine

Question

I am running docker on windows 10 laptop, I've set up my first container running Elasticsearch using a Dockerfile and it works. Every time I stop the container and start it again the data is gone.

On my windows machine I created a folder in location C:/Docker/esdata and in my elasticsearch.yml I've added path.data: /usr/share/elasticsearch/data is were data is. In the Dockerfile I added:

VOLUME /c/Docker/esdata:/usr/share/elasticsearch/data

but this still doesn't work, can someone tell me what i'm doing wrong.

Answer 1

Your Dockerfile specifies the attributes of the image... the things that are the same no matter where you run the container.

VOLUME /c/Docker/esdata:/usr/share/elasticsearch/data

Is not doing what you think it is doing- you cannot force someone who runs your image later to mount that specific folder. (VOLUME takes a single argument, the path inside the container that is to become seperate from the copy-on-write file system) Instead, you mount the volume at run time with a docker run command...

docker run -v /c/Docker/esdata:/usr/share/elasticsearch/data

This mounts a path on your machine to a path in the running container. However, as pointed out above, /c/Docker is not available to the virtual machine running docker, you will have to do something more like

/c/Users/Docker/esdata:/usr/share/elasticsearch/data