This may be common knowledge so if it is redundant, apologies.
My ISO domain did not populate automatically but with some research I found out how to
utilize it and populate it.
If you have it in place with the correct permissions and security, you can manually
populate it using the api.
From the engine host at the command prompt:
# ovirt-iso-uploader list
This gives you the name of your iso domain. If it prompts for a passwd, it should the the
same as the admin@internal login.
The to upload files and populate it:
ovirt-iso-uploader -i ISO upload *.iso or *vfd for floppy images
I hope this helps.