Problems with masterURL, masterPublicURL, and Named Certificates in OpenShift

Issue

• Trying to protect master API URL with valid SSL certificate to avoid browser warnings etc.
• Using the documentation to set up custom certificates
• Using advanced install to set up custom certificates
• masterPublicURL, masterURL, and load balancer all have same domain name

masterPublicURL: https://server.example.com
masterURL: https://server.example.com

• What domain names need to be resolvable with custom SSL certificates?
• cluster hostname variables are the same:

openshift_master_cluster_hostname=internal-openshift.example.com
openshift_master_cluster_public_hostname=openshift.example.com

• How do I change the masterURL?