title: How to push a tar archive to private docker registry?
body: <p>Now I have such a requirement，firstly I need export a container’s filesystem as a tar archive, then I need push this tar to my own docker registry.So could I push a tar file which is exported by using <code>docker export image_name</code> to my private registry.Before this I only know I could push a local image to registry by using <code>docker push image_name</code>. Thanks!  </p>