====== Installing FreeBSD 9.x Root on ZFS using GPT ======

===== Creating a bootable ZFS Filesystem =====

  - Boot %%FreeBSD%% Install USB Memstick

  - Choose %%LiveCD%% when asked

  - Mount Root filesystem read-writeable to prevent further problems

<code>
mount -rw /
</code>

  - Create GPT Disk

<code>
Fixit# gpart create -s gpt ad0
</code>

<callout type="info">
**Note:**

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

<code>
Fixit# gpart destroy ad0
</code>

  - Create the boot, swap and zfs partitions

<code>
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
</code>

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.

<callout type="info">
**Note:**

  - While a [[/RootOnZFS|ZFS Swap Volume]] can be used instead of the freebsd-swap partition, crash dumps can't be saved to the ZFS Swap Volume.
</callout>

  - Install the Protected MBR (pmbr) and gptzfsboot loader

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

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:

<code>
Fixit# sysctl kern.geom.debugflags=0x10
</code>

  - Load ZFS kernel module

<code>
Fixit# kldload opensolaris.ko
Fixit# kldload zfs.ko
</code>

  - Create ZFS Pool zroot

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

<callout type="info">
**Note:**

zroot is the name of the ZFS Pool, it could be anything (i.e. tank, data, ...)
</callout>

===== Installing FreeBSD to the ZFS filesystem =====

  - Create ZFS filesystem hierarchy\\ \\ 

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

<code>
Fixit# zfs set checksum=fletcher4					zroot
</code>

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

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

<code>
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
</code>

<callout type="info">
**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.
</callout>

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

<code>
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
</code>

<callout type="info">
**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.
</callout>

  - Install %%FreeBSD%% to zroot using bsdinstall

    - When asked about Partitioning choose "shell"
    - Mount filesystem to /mnt

<code>
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
</code>

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

<code>
exit
</code>

  - Make /var/empty readonly

<code>
Fixit# zfs set readonly=on zroot/var/empty
</code>

  - chroot into /zroot

<code>
Fixit# chroot /mnt
</code>

  - Create /etc/rc.conf

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

  - Create /boot/loader.conf

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

  - Exit from chroot

<code>
Fixit# exit
</code>

  - Install zpool.cache to the ZFS filesystem

<code>
Fixit# cp /boot/zfs/zpool.cache /boot/zfs/zpool.cache
</code>

===== Finish install =====

  - Create /etc/fstab

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

  - Unmount all zfs filesystems

<code>
Fixit# zfs unmount -a
</code>

  - Change mount points for zroot pool 

<code>
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
</code>

  - Exit Fixit mode, and then bsdinstall.  Remove the %%FreeBSD%% install DVD/Memstick and the system will boot using the ZFS root.

----

{{tag>Zfs}}