Installing FreeBSD Root on ZFS using UFS /boot
1. Creating a bootable ZFS Filesystem
- Boot FreeBSD install DVD or USB Memstick
- Choose Fixit option in sysinstall
Create MBR disk
If you are installing on an New drive, you will need to create the MBR geometry first:Fixit# gpart create -s mbr ad0
Create Slice using gpart
This example already has two slices defined on the drive.Fixit# gpart show ad0 => 63 625142385 ad0 MBR (289G) 63 209712447 1 !7 (100G) 209712510 417690 2 !136 (204M) 210130200 415012248 - free - (198G)Create a third slice using the size parameter. You may omit the size to use the remainder of the disk. Then create a BSD partition table on the new slice.
Fixit# gpart add -s 198G -t freebsd ad0 ad0s3 added Fixit# gpart create -s BSD ad0s3 ad0s3 created
And examine the result:Fixit# gpart show ad0 => 63 625142385 ad0 MBR (289G) 63 209712447 1 !7 (100G) 209712510 417690 2 !136 (204M) 210130200 415012248 3 freebsd (198G)Note:
- Sizes and offsets are specified in sectors (1 sector is typically 512 bytes) but can also be specified in MB or GB by adding a 'M' or 'G' suffix.
Set partition active (Optional)
Some BIOSes might require setting a Slice active. Here we set partition 1 (the Windows Partiton) as the active partition.Fixit# gpart set -a active -i 1 ad0
- Create partitions (ad0s3a, ad0s3b, ad0s3d)
Fixit# gpart show ad0s3 => 0 415012248 ad0s3 BSD (198G) 0 415012248 ad0s3 - free - (198G)Fixit# gpart add -s 1G -t freebsd-ufs ad0s3 ad0s3a added
Fixit# gpart show ad0s3 => 0 415012248 ad0s3 BSD (198G) 0 2097152 1 freebsd-ufs (1G) 2097152 412915096 - free - (197G)Fixit# gpart add -s 4G -t freebsd-swap ad0s3 ad0s3b added
Fixit# gpart show ad0s3 => 0 415012248 ad0s3 BSD (198G) 0 2097152 1 freebsd-ufs (1.0G) 2097152 8380827 2 freebsd-swap (4.0G) 10477979 404534269 - free - (193G)Fixit# gpart add -t freebsd-zfs ad0s3 ad0s3a added
Fixit# gpart show ad0s3 => 0 415012248 ad0s3 BSD (198G) 0 2097152 1 freebsd-ufs (1.0G) 2097152 8380827 2 freebsd-swap (4.0G) 10477979 404534269 4 freebsd-zfs (193G)Note:
While a ZFS Swap Volume can be used instead of the freebsd-swap partition, crash dumps can't be created on the ZFS Swap Volume.
- Sizes and offsets are specified in sectors (1 sector is typically 512 bytes) but can also be specified in MB and GB by using a 'M' or 'G' suffix.
- Install boot Manager
Fixit# gpart bootcode -b /mnt2/boot/boot0 ad0 bootcode written to ad0
It's ok if you get an "unknown class" message here, but it you get "failed to install" or the like, you'll need to try again after making sure that nothing is mounted from /dev/ad0.Fixit# gpart bootcode -b /mnt2/boot/boot ad0s3 bootcode written to ad0s3
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 /mnt2/boot/kernel/opensolaris.ko Fixit# kldload /mnt2/boot/kernel/zfs.ko
- Create ZFS Pool zroot
Fixit# mkdir /boot/zfs Fixit# zpool create zroot /dev/ad0s3d Fixit# zpool set bootfs=zroot zroot
Note:
- zroot is the name of the ZFS Pool, it could be anything (i.e. tank, data, ...)
- Create UFS /boot
Fixit# mkdir /zroot/bootdir Fixit# newfs /dev/ad0s3a Fixit# mount /dev/ad0s3a /zroot/bootdir
2. Installing FreeBSD to the ZFS filesystem
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 compression=lzjb -o exec=off -o setuid=off zroot/var/crash 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=gzip -o exec=off -o setuid=off zroot/var/mail Fixit# zfs create -o exec=off -o setuid=off zroot/var/run 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 compression 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
Fixit# cd /dist/8.0-* Fixit# export DESTDIR=/zroot Fixit# for dir in base catpages dict doc games info lib32 manpages ports; \ do (cd $dir ; ./install.sh) ; done Fixit# cd src ; ./install.sh all Fixit# cd ../kernels ; ./install.sh generic Fixit# cd /zroot/boot ; cp -Rlp GENERIC/* /zroot/boot/kernel/ - Make /var/empty readonly
Fixit# zfs set readonly=on zroot/var/empty
- chroot into /zroot
Fixit# chroot /zroot
- Create /etc/rc.conf
Fixit# echo 'zfs_enable="YES"' > /etc/rc.conf Fixit# echo 'hostname="beastie.mydomain.local"' >> /etc/rc.conf Fixit# echo 'ifconfig_re0="DHCP"' >> /etc/rc.conf
Note:
- Replace re0 with the name of the Network interface for the new system
- Create /boot/loader.conf
Fixit# echo 'zfs_load="YES"' > /boot/loader.conf Fixit# echo 'vfs.root.mountfrom="zfs:zroot"' >> /boot/loader.conf
- Change root's password
Fixit# passwd
- Set the local time zone
Fixit# tzsetup
- Create /etc/mail/aliases.db
Fixit# cd /etc/mail Fixit# make aliases
- Exit from the /zroot
Fixit# umount /dev Fixit# exit
- Install zpool.cache to the ZFS filesystem
Fixit# cp /boot/zfs/zpool.cache /zroot/boot/zfs/zpool.cache
3. Finish install
- Move /zroot/boot into /zroot/bootdir
Fixit# cd /zroot Fixit# mv boot bootdir/ Fixit# ln -s bootdir/boot /zroot/boot Fixit# chflags -h sunlink /zroot/boot
- Create /etc/fstab
Fixit# mkdir /zroot/etc Fixit# cat << EOF > /zroot/etc/fstab # Device Mountpoint FStype Options Dump Pass# /dev/ad0s3a /bootdir ufs rw 0 0 /dev/ad0s3b none swap sw 0 0 EOF
- export LD_LIBRARY_PATH
Fixit# export LD_LIBRARY_PATH=/mnt2/lib
- Unmount all zfs filesystems
Fixit# umount /zroot/bootdir 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
- Exit Fixit mode, and then sysinstall. Remove the FreeBSD install DVD/Memstick and the system will boot using the ZFS root.