Unable to register with Redhat in OSE

I'm almost complete in getting my deployment of OpenShift going but I'm running into something strange. DNS is working on the device I have tested that and the OS is RHEL7.4.

The command OpenShift uses this to register:

/usr/sbin/subscription-manager register --baseurl https://cdn.redhat.com --insecure --username username --password 'password'

This comes back with:

Unable to reach the server at :443/subscription