I have 3 x 4 TB disks in a NAS that I want to group together and access as if they were one whole 'unit' of some kind. I also have a 250GB disk containing the OS - this is full of films and tv shows currently. I thought zfs sounded good so I created a raidz zpool, after installing the ppa sudo zpool create store raidz /dev/sdb /dev/sdc /dev/sdd and set the mountpoint to /mnt/store sudo zfs set mountpoint=/mnt/store /store checked it was successful - I think it was sudo zfs list NAME USED AVAIL REFER MOUNTPOINT store 266K 7.16T 170K /mnt/store Then I wanted to move over a whole load of files from my home directory. I went to where the to-be-copied folder was (called media) and entered sudo cp -R * /mnt/store cp: cannot create directory `/mnt/store/media': No space left on device It seems like it's not copying over to the new filesystem I made (or thought I did). I've never really done this type of thing until a few days ago so may be running before I can walk... is this not the right way to copy files across? I've only used windows before so the idea of mountpoints is a bit mind boggling. I'm using XBMCbuntu 12 beta 2.0 which is based on 12.04. Will retry with normal Ubuntu 12.04 desktop to see if that's the problem. thanks for the help!