I am trying to duplicate the GUI functionality of adding an existing disk (not create new) to a vm and specifying the .vmdk file to be used. From the GUI you would edit, then add and choose Hard disk. Then choose select Use an existing hard disk and drilling down into the datastore to the specific .vmdk file.
After selecting the .vmdk, then choose the SCSI device and channel and finish the wizrard. After the disk is added, then come back and select the hard disk and choose Manage Paths to change the path policy from Round Robin to MRU.
Ideally, the user would be able to use something like VC:Datastore to use a tree view to point to the vmdk when adding the disk, however I have tried VC:Datstore and it only allows you to go as far as the datastore but not further to specify the disk.
Thanks