Installing FreeBSD 9.x Root on ZFS using GPT

Boot FreeBSD Install USB Memstick

Choose LiveCD when asked

Mount Root filesystem read-writeable to prevent further problems

mount -rw /

Create GPT Disk

Fixit# gpart create -s gpt ad0

Note:

If the disk already contains a partitioning scheme, and this scheme would first need to be destroyed using:

Fixit# gpart destroy ad0

Create the boot, swap and zfs partitions

Fixit# gpart add -s 64K -t freebsd-boot ad0
Fixit# gpart add -s 4G -t freebsd-swap -l swap0 ad0
Fixit# gpart add -t freebsd-zfs -l disk0 ad0

This creates 3 partitions. The first partition will contains the gptzfsboot loader which will be able to load /boot/loader or /boot/zfsloader (9.0-CURRENT) from a ZFS partition. The second partition is a 4 GB swap partition. The third partition is dedicated to the ZFS zpool and uses the remaining space on the disk.

Note:

While a ZFS Swap Volume can be used instead of the freebsd-swap partition, crash dumps can't be saved to the ZFS Swap Volume.

Install the Protected MBR (pmbr) and gptzfsboot loader

Fixit# gpart bootcode -b /boot/pmbr -p /boot/gptzfsboot -i 1 ad0

This may fail with an “operation not permitted” error message, since the kernel likes to protect critical parts of the disk. If this happens for you, run:

Fixit# sysctl kern.geom.debugflags=0x10

Load ZFS kernel module

Fixit# kldload opensolaris.ko
Fixit# kldload zfs.ko

Create ZFS Pool zroot

Fixit# zpool create zroot /dev/gpt/disk0
Fixit# zpool set bootfs=zroot zroot

Note:

zroot is the name of the ZFS Pool, it could be anything (i.e. tank, data, …)

Create ZFS filesystem hierarchy

The fletcher4 algorithm should be more robust than the fletcher2 algorithm.

Fixit# zfs set checksum=fletcher4					zroot

Fixit# zfs create -o compression=on	-o exec=on	-o setuid=off	zroot/tmp
Fixit# chmod 1777 /zroot/tmp

Fixit# zfs create							zroot/usr
Fixit# zfs create							zroot/usr/home
Fixit# cd /zroot ; ln -s /usr/home home

Fixit# zfs create -o compression=lzjb 			-o setuid=off	zroot/usr/ports
Fixit# zfs create -o compression=off	-o exec=off	-o setuid=off	zroot/usr/ports/distfiles
Fixit# zfs create -o compression=off	-o exec=off	-o setuid=off	zroot/usr/ports/packages

Note:

If you use nullfs or nfs to mount /usr/ports to different locations/servers, you will also need to nullfs/nfs mount /usr/ports/distfiles and/or /usr/ports/packages.

Fixit# zfs create -o compression=lzjb 	-o exec=off	-o setuid=off	zroot/usr/src

Fixit# zfs create							zroot/var
Fixit# zfs create			-o exec=off	-o setuid=off	zroot/var/db
Fixit# zfs create -o compression=lzjb 	-o exec=on	-o setuid=off	zroot/var/db/pkg
Fixit# zfs create			-o exec=off	-o setuid=off	zroot/var/empty
Fixit# zfs create -o compression=lzjb 	-o exec=off	-o setuid=off	zroot/var/log
Fixit# zfs create -o compression=lzjb 	-o exec=on	-o setuid=off	zroot/var/tmp
Fixit# chmod 1777 /zroot/var/tmp

Note:

Compression may be set to on, off, lzjb, gzip, gzip-N (where N is an integer from 1 (fastest) to 9 (best compresion ratio. gzip is equivalent to gzip-6).
Compression will cause some latency when accessing files on the ZFS filesystems. Use compression on ZFS filesystems which will not be accessed that often.

Install FreeBSD to zroot using bsdinstall

When asked about Partitioning choose “shell”
Mount filesystem to /mnt

zfs set mountpoint=/mnt zroot
zfs set mountpoint=/mnt/tmp zroot/tmp
zfs set mountpoint=/mnt/usr zroot/usr
zfs set mountpoint=/mnt/var zroot/var

zfs mount -a

Exit shell and go back to bsdinstall to let it install your FreeBSD system

exit

Make /var/empty readonly

Fixit# zfs set readonly=on zroot/var/empty

chroot into /zroot

Fixit# chroot /mnt

Create /etc/rc.conf

Fixit# echo 'zfs_enable="YES"' >> /etc/rc.conf

Create /boot/loader.conf

Fixit# echo 'zfs_load="YES"' > /boot/loader.conf
Fixit# echo 'vfs.root.mountfrom="zfs:zroot"' >> /boot/loader.conf

Exit from chroot

Fixit# exit

Install zpool.cache to the ZFS filesystem

Fixit# cp /boot/zfs/zpool.cache /boot/zfs/zpool.cache

Create /etc/fstab

Fixit# cat << EOF > /mnt/etc/fstab
# Device			Mountpoint		FStype	Options		Dump	Pass#
/dev/gpt/swap0			none			swap	sw		0	0
EOF

Unmount all zfs filesystems

Fixit# zfs unmount -a

Change mount points for zroot pool

Fixit# zfs set mountpoint=legacy zroot
Fixit# zfs set mountpoint=/tmp zroot/tmp
Fixit# zfs set mountpoint=/usr zroot/usr
Fixit# zfs set mountpoint=/var zroot/var