Comment 2 for bug 1630203

So talking from my experience, the steps needed to allow full disk images is:
1. Provide a new way of building images inside tripleo. Currentl, this basically needs to use vm (or other custom element) instead of baremetal element, in diskimage-builder config. Please not that this effort https://review.openstack.org/#/c/375261/ is also related.
2. Update TripleO "openstack image upload" call, to don't require overcloud-full.initrd and vmlinuz files, in the case of full disk images. If that's the case, no kernel and initrd flags need to be added as glance properties on overcloud-full.qcow2
3. Ensure that ironic supports iscsi deployment correctly. Currently this change is needed: https://review.openstack.org/381893