# gpart create -s gpt ada0
# gpart add -t freebsd-boot -l gpboot -s 128 ada0
# gpart bootcode -b /boot/pmbr -p /boot/gptboot -i 1 ada0
# gpart add -t freebsd-swap -l gpswap -s 512M ada0
# gpart add -t freebsd-ufs -l gproot -s 2G ada0
# gpart add -t freebsd-ufs -l gpvar -s 1G ada0
# gpart add -t freebsd-ufs -l gptmp -s 1G ada0
# gpart add -t freebsd-ufs -l gpusr ada0

# gpart show

# newfs -U /dev/gpt/gproot
# newfs -U /dev/gpt/gpvar
# newfs -U /dev/gpt/gptmp
# newfs -U /dev/gpt/gpusr

# mount /dev/gpt/gproot /mnt
# mkdir /mnt/var /mnt/tmp /mnt/usr
# mount /dev/gpt/gpvar /mnt/var
# mount /dev/gpt/gptmp /mnt/tmp
# mount /dev/gpt/gpusr /mnt/usr

# vi /etc/fstab

/dev/gpt/gpswap none swap sw 0 0
/dev/gpt/gproot / ufs rw 1 1
/dev/gpt/gpvar /tmp ufs rw 2 2
/dev/gpt/gptmp /usr ufs rw 2 2
/dev/gpt/gpusr /var ufs rw 2 2