Assume the following drive setup (with ZFS):
Controller 1 Drive1 Drive4 Drive7 Drive10 Controller 2 Drive2 Drive5 Drive8 Drive11 Controller 3 Drive3 Drive6 Drive9 Drive12
vdev1: drive1, drive2, drive3 vdev2: drive4, drive5, drive6 vdev3: drive7, drive8, drive9 vdev4: drive10, drive11, drive12
Is it better (for reliability) to add all vdevs to the same zpool, or have separate zpools (one for each vdev)? Also, if we lost a single vdev, would we lose the entire array? We don't need all the storage capacity in one place - the smaller zpools would be find from the storage standpoint.
Update: For 3dinfluence's question about the boot pool, that will be on a RAID1 set. I don't like mixing the OS and my multi-terabyte RAID arrays.