While attempting to create a 2-way LVM mirror this weekend on my Fedora Core 5 workstation, I received the following error:
$ lvcreate -L1024 -m 1 vgdata
Not enough PVs with free space available for parallel allocation. Consider --alloc anywhere if desperate.
Since the two devices were initialized specifically for this purpose and contained no other data, I was confused by this error message. After scouring Google for answers, I found a post that indicated that I needed a log LV for this to work, and the log LV had to be on it’s own disk. I am not sure about most people, but who on earth orders a box with three disks? Ugh!