So, Drobo says it's because of the drives I'm using. I'd planned to swap them out for bigger ones anyway, so I went ahead and ordered them ahead of plan. They should arrive tonight.
Meanwhile, spent the day trying to install ubuntu on the Atomic Pis in as automated a way as possible. PXE just Doesn't Fucking Work and I'm sick of fighting with it. I finally managed to put together a combination of kickstart file, preseed file, and post-install script that work if I boot the machine off a (virtual) cd and tell it to use them. About 9 hours of repeatedly reinstalling the OS on one machine debugging that setup until it worked the way I wanted, and now I've just finished the third of six.
Plan for rearranging the bedrooms is moving forward. I think we've got layouts that work now, so the next step is to start moving things out of the sitting room so we can get to the back wall, then get the electrician in to run some circuits. That's going to be hella expensive. And then I'll need to buy a new bed, also expensive. And between those two things, there goes the up front cost for my Tesla, pushing THAT out probably another year. ::P Note to self: win the lottery already, geez.