That is about changing the default config, so that if you put a non fully qualified name it might choose a different registry from Docker Hub. You can always pu

That is about changing the default config, so that if you put a non fully qualified name it might choose a different registry from Docker Hub. You can always pull a fully qualified name on any version of Docker. Red Hat just wanted their install to pull from a different registry if you did "docker run ubuntu" which is kind of confusing for users. You can always just do docker run mydomain.com/ubuntu or whatever on any version.