#	Procedure applied to multiple Raspberry Pi 4's each with 8 GiB RAM;
# earliest approach used FreeBSD 13.2 and set up zpool(8) with 1/2 kiB blocks,
# which worked with very poor performance

#	Partition the 'disk' with gpt
gpart create -s gpt da0

#	First free block for partitions will be either '34', '40', '48' or '64'
# Size the efi partition to make the first block for the following partition
# 131072 (64 MiB aligned); this calls for a size of '131038', '131032',
# '131024' or '131008'
#	The SD card image uses 50 MB for efi, which is plenty for now; I've
# dealt with many systems that have gone through so many release upgrades on
# the same disk that starting boot partition becomes too small
#	This example matches the case where the first free block is '40'
gpart add -t efi -s 131032 -l efi da0
gpart set -a bootme -i 1 da0

#	If dedicating a swap partition, size (in multiples of x MiB) the
# system partition to leave enough space for it; from skimming through reports
# on zfs-swap, it looks adequate to be all swap since FreeBSD 11 or 12, so this
# is technically optional, special case, cautious, or because only a swap
# partition works as a dump device
gpart add -t freebsd-zfs -s xxxxxxxxx -l freebsd da0
gpart add -t freebsd-swap -l swap da0

#	Set zpool(8) to use 4kiB blocks (or larger, 12->4k, 13->8k, 14-> 16k);
# write performance with the default 9 (1/2k) has been very poor with the SD
# cards I've used
sysctl vfs.zfs.min_auto_ashift=12

#	Use geom to get the gptid (is there a better way to do this?)
geom part list | grep -A6 da0p2
zpool create -R /mnt -O canmount=off zroot /dev/gptid/xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx

#	Sources disagree about the specific options on the boot environment
# container; such as 'noauto' vs 'off' for canmount
zfs create -o canmount=noauto -o mountpoint=none zroot/ROOT

#	Filesystems based on an older ZFS example setup from the FreeBSD wiki
# plus local common use cases
zfs create -o canmount=noauto -o mountpoint=/ zroot/ROOT/default
zpool set bootfs=zroot/ROOT/default zroot
zfs mount zroot/ROOT/default
zfs create -o mountpoint=/var zroot/var
zfs create -o compression=on -o exec=off -o setuid=off zroot/var/crash
zfs create -o exec=off -o setuid=off zroot/var/db
zfs create -o exec=off -o setuid=off zroot/var/empty
zfs create -o compression=on -o exec=off -o setuid=off zroot/var/log
zfs create -o compression=gzip -o exec=off -o setuid=off zroot/var/mail
zfs create -o exec=off -o setuid=off zroot/var/run
zfs create -o exec=off -o setuid=off zroot/var/spool
zfs create -o compression=on -o exec=on -o setuid=off zroot/var/tmp
zfs create -o compression=on zroot/var/www
zfs create -o compression=on -o exec=on -o setuid=off zroot/var/db/pkg
zfs create -o mountpoint=/usr zroot/usr
zfs create zroot/usr/local
zfs create -o compression=on -o exec=off -o setuid=off zroot/usr/src
zfs create zroot/usr/obj
zfs create -o compression=on -o setuid=off zroot/usr/ports
zfs create -o compression=off -o exec=off -o setuid=off zroot/usr/ports/distfiles
zfs create -o compression=off -o exec=off -o setuid=off zroot/usr/ports/packages
zfs create -o mountpoint=/home -o setuid=off zroot/home

#	Get the system from the default SD card image; the following shows the
# case where mdconfig sets up md0
mdconfig -f /var/spool/img/freebsd/FreeBSD-14.0-RELEASE-arm64-aarch64-RPI.img
cd /mnt
dump -0af - /dev/md0s2a | restore -rf -
rm restoresymtable

#	Copy the efi data from the SD card image
newfs_msdos -F 32 -L EFI -c 1 /dev/da0p1
mount -t msdosfs -o noatime /dev/da0p1 /mnt/boot/efi
mount -r -t msdosfs /dev/md0s1 /mnt/mnt
cd /mnt/mnt
pax -r -w -pe * /mnt/boot/efi/

#	Done with the source image
cd
umount /mnt/mnt
mdconfig -d -u 0

#	Optional, configure /mnt/boot/efi/config.txt, such as setting monitor
# resolution

#	Optional, add (more) swap
zfs create -V xxG zroot/SWAP
zfs set org.freebsd:swap=on zroot/SWAP
zfs set checksum=off zroot/SWAP

#	Set access
zfs set readonly=on zroot/var/empty

#	Add zfs to /mnt/boot/loader.conf; along with the 'zpool set bootfs'
# line above, this enables mounting / during boot
cat >>/mnt/boot/loader.conf <<EOF
zfs_load="YES"
EOF

#	Set main devices in /mnt/etc/fstab; adjust swap and tmpfs details for
# the actual system setup
cat >/mnt/etc/fstab <<EOF
# Specification	File		Type	Options			Dump Pass#
/dev/gpt/swap	none		swap	sw
/dev/gpt/efi	/boot/efi	msdosfs rw,noatime
tmpfs           /tmp		tmpfs	rw,mode=01777,size=2G
EOF

#	Enable zfs in /mnt/etc/rc.conf (and remove growfs_enable); this
# effectively enables 'zfs mount -a' during boot
cat >>/mnt/etc/rc.conf <<EOF
zfs_enable="YES"
EOF

umount /mnt/boot/efi
zpool export zroot