Is it possible to clone XDCAM discs on a Mac using two PDW-U1/2s? Everything I've found on the topic said it wasn't possible, but all of the articles were from 2011 or earlier. Has anything been released in the past few years to make this process possible?
Frankly your post frightens me a little as this has always been possible and very easy to do. There was a brief period of a couple of months when the U1 first came out where we didn't have a USB driver for the Mac (it was delayed) and the U1 was rendered read-only but beyond that this has always been very easy to do.
The simplest way to clone a disc is to copy the high-res .mxf files from the \Clip folder on one disc to the \Clip folder on another disc. You do not need to copy the XMLs or proxy files; they will be automatically generated when the .mxfs land in \Clip.
You can use Content Browser to do this as well-- highlight the first U1/U2 in one of the navigation windows and then drag the thumbnails from the drive to another connected U1/U2.
Alternately if you only had one drive you could copy the clips to your Mac and then drag them to \Clip on a seconds disc.
Let me know if you run into problems making this work.
For AMA volume/folder linking to work you need a mediapro.xml file and a /CLIP folder. These are what the plugin is looking for. If you don't have these you don't have a virtual disc and need to link the files using the 'XAVC/XDCAM *mxf' option.