How to copy files from host to Docker container?

Question

I am trying to build a backup and restore solution for the Docker containers that we work with.

I have Docker base image that I have created, ubuntu:base

Answer 1

If the host is CentOS or Fedora, there is a proxy NOT in /var/lib/docker/aufs, but it is under /proc:

cp -r /home/user/mydata/* /proc/$(docker inspect --format "{{.State.Pid}}" )/root

This cmd will copy all contents of data directory to / of container with id "containerid".