Let’s say you have your vCloud Director cells behind a load balancer.
You try to upload your files (.iso and .ovf images for either a vApp or media and receive an error message like:
Error: Transferring files
On page 98 of the vdc_15_admin_guide.pdf you will find a paragraph pointing out that you need to fill in the API field for uploads to work.
During the initial configuration of each cloud cell, you specified an HTTP service IP address. By default, vCloud Director uses that address in the XML responses from the REST API and as the upload target for the transfer service (for uploading vApp templates and media). To use a different address, specify a public REST API base URL.
I had missed that in my new setup of vCloud Director 1.5 and a helpful VMware employee answered my questions in the Communities.