http://mabufs.i2p/blog/freebsd-zfs-di
We will look at the existing partition: gpart show ada1 If the partition exists you need to delete it: gpart destroy -F ada1 and create a new partition table: gpart create -s gpt /dev/ada1 If you need an extra swap partition, create one too: gpart add -t freebsd-swap -s 2G /dev/ada1 Next we create the file partition itself: gpart add -t freebsd-zfs /dev/ada1 Check what happened: gpart show ada1 If everything is correct, create a new filesystem: ...