Deploying host vm using rancher

To add a host, I am using vsphere machine driver.

My company uses proxy and using the boot2docker image URL, I get a timed out error. Hence I want to download the ISO manually and use it.

If I upload it onto the datastore, what format I should use to declare that path

There is no support in the docker-machine driver for reading the ISO from the vmware store (despite it then storing it in there).