login

Usage: docker login [OPTIONS] [SERVER]

Register or log in to a Docker registry server, if no server is
specified "https://index.docker.io/v1/" is the default.

  -e, --email=""       Email
  --help=false         Print usage
  -p, --password=""    Password
  -u, --username=""    Username

If you want to login to a self-hosted registry you can specify this by adding the server name.

example:
$ docker login localhost:8080