Docker Volume
It is possible to store data within the writable layer of a container, but there are some downsides: The data won't persist when that container is no lunger running. A container's writable layer is tightly coupled to the host machine where the container is running. Writing into a container's writable layers requires a storage drive to manage the filesystem. the storage driver provides a union filesystem, using the Linuz kernel. -Stop the running container # docker stop nginx nginx is the container name that had assigned before. -Run new container with volume # docker run -d --name nginx-persistent -v nginx-volume:/usr/share/nginx/html/ -p 8080:80 custom-nginx -Create & Modify some file on the mounter volume # echo "this is created in a persistent volume" > /var/lib/docker/volumes/nginx-volume/_date/index.html -remove & recreate the container to verify the mounted data is persistent