Root on ZFS FreeBSD 9 (Updated)

This is an updated guide showing how you can install a full ZFS system using FreeBSD9.

In this guide I will demonstrate how you can install a fully functional full ZFS FreeBSD9 using a GPT scheme. We will also use ZFS for SWAP

You can use this as a reference guide for a single or mirror installation.

(1) Boot from a FreeBSD9 installation DVD or memstick and choose “Live CD”.

(2) Create the necessary partitions on the disk(s) and add ZFS aware boot code.

a) For a single disk installation.

gpart create -s gpt ada0
gpart add -b 34 -s 94 -t freebsd-boot ada0
gpart add -t freebsd-zfs -l disk0 ada0
gpart bootcode -b /boot/pmbr -p /boot/gptzfsboot -i 1 ada0

b) Repeat the procedure for the second drive if you want a mirror installation.

gpart create -s gpt ada1
gpart add -b 34 -s 94 -t freebsd-boot ada1
gpart add -t freebsd-zfs -l disk1 ada1
gpart bootcode -b /boot/pmbr -p /boot/gptzfsboot -i 1 ada1

(3) Create the pool.(ignore any warnings regarding mounting)

a) For a single disk installation.

zpool create zroot /dev/gpt/disk0

b) For a mirror installation.

zpool create zroot mirror /dev/gpt/disk0 /dev/gpt/disk1

(4) Set bootfs property, checksums and mountpoints.

zpool set bootfs=zroot zroot
zfs set checksum=fletcher4 zroot
zfs set mountpoint=/mnt zroot

(5)) At this point export and import the pool while preserving zroot.cache in /var/tmp.

zpool export zroot
zpool import -o cachefile=/var/tmp/zpool.cache zroot

(6) Create appropriate filesystems (feel free to improvise!).

zfs create zroot/usr
zfs create zroot/usr/home
zfs create zroot/var
zfs create -o compression=on -o exec=on -o setuid=off zroot/tmp
zfs create -o compression=lzjb -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 compression=lzjb -o exec=off -o setuid=off zroot/usr/src
zfs create -o compression=lzjb -o exec=off -o setuid=off zroot/var/crash
zfs create -o exec=off -o setuid=off zroot/var/db
zfs create -o compression=lzjb -o exec=on -o setuid=off zroot/var/db/pkg
zfs create -o exec=off -o setuid=off zroot/var/empty
zfs create -o compression=lzjb -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 compression=lzjb -o exec=on -o setuid=off zroot/var/tmp

(7) Add swap space and disable checksums. In this case I add 4GB of swap.

zfs create -V 4G zroot/swap
zfs set org.freebsd:swap=on zroot/swap
zfs set checksum=off zroot/swap

(8) Create a symlink to /home and fix some permissions.

chmod 1777 /mnt/tmp
cd /mnt ; ln -s usr/home home
chmod 1777 /mnt/var/tmp

(9) Instal FreeBSD.

sh
cd /usr/freebsd-dist
export DESTDIR=/mnt
for file in base.txz lib32.txz kernel.txz doc.txz ports.txz src.txz;
do (cat $file | tar --unlink -xpJf - -C ${DESTDIR:-/}); done

(10) Copy zpool.cache (very important!!!)

cp /var/tmp/zpool.cache /mnt/boot/zfs/zpool.cache

(11) Create the rc.conf, loader.conf and an empty fstab (otherwise the system will complain).

echo 'zfs_enable="YES"' &gt;&gt; /mnt/etc/rc.conf
echo 'zfs_load="YES"' &gt;&gt; /mnt/boot/loader.conf
echo 'vfs.root.mountfrom="zfs:zroot"' &gt;&gt; /mnt/boot/loader.conf
touch /mnt/etc/fstab

(12) Unmount everything and fix mountpoints for system boot.

zfs set readonly=on zroot/var/empty
zfs umount -af
zfs set mountpoint=legacy zroot
zfs set mountpoint=/tmp zroot/tmp
zfs set mountpoint=/usr zroot/usr
zfs set mountpoint=/var zroot/var