So ... I've spent the last 24 hours shuffling VHDs around because we ran into a problem a few weeks ago where the VHD expanded larger than the physical drive. Ooops. That's what happens when you configure a dynamically expanding VHD to be 350GB and drop it onto a 300GB drive. No advanced math degree required here.
So, to fix the problem, I've had to move the data from one spot to another, replace the drives in the servers, and then move the data back. Fun times. It's about 1.2TB of data that I have to move twice.
Windows 2008 includes the demonic "Scalable Networking Pack" components that caused so much grief in Windows 2003 SP2. Word to the wise--if you haven't tested everything out, TURN OFF RECEIVE SIDE SCALING when trying to transfer files. If for some reason the RSS handshake doesnt' happen properly, you data barely goes anywhere.
To fix it, go to you Network Connections, click Manage connections, and then select an adapter. Right-click > Properties, and then click Configure next to the adapter. On the Advanced tab, select Receive Side Scaling and set it to "disabled." Do this on all servers. Reboot.
Watch everything go much faster.