I am working on a home server running EFI. i have Ubuntu 15.04 installed
and am looking to find out if there is a way to migrate to raid on a
running system.

In theory i should be able to do this by creating a degraded portion of the
raid volume on the empty disk, extend/move my LVM to that disk then rebuild
the original disk as part of that raid volume.

I was wondering if anyone had some documentation of information i could
read about this scenario. Added complication so far seems to be that this
is a 2013 mac mini.

Thanks in advance.

-- 
A mouse trap, placed on top of your alarm clock, will prevent you from
rolling over and going back to sleep after you hit the snooze button.

Stephen