ZFS Install Guide

Guide is currently being restyled.

This tutorial will show you how to install Funtoo on ZFS (rootfs). This tutorial is meant to be an "overlay" over the Regular Funtoo Installation. Follow the normal installation and only use this guide for steps 2, 3, and 8.

Since ZFS was really designed for 64 bit systems, we are only recommending and supporting 64 bit platforms and installations. We will not be supporting 32 bit platforms!

Setting up your environment

In order for us to install Funtoo on ZFS, you will need an environment that provides the ZFS tools. We will be downloading two things:

1. System Rescue CD,
2. ZFS System Rescue Module (SRM)

This is just a file that when combined with System Rescue CD, gives you those tools.

Name: SystemRescueCd-x86-3.2.0 (353 MiB)
Release Date: 2013-01-07md5sum 90528f0c4b861363992fd9cbcc52d00a

Download System Rescue CD 3.2.0
Download the ZFS System Rescue Module

Follow the instructions here to download and place the srm into your flash drive.

Creating partitions

There are two ways to partition your disk: You can use your entire drive and let ZFS automatically partition it for you, or you can do it manually.

Using your entire disk drive is recommended since ZFS turns on/off a few settings. For one, if you use your whole-disk, ZFS will set the I/O elevator for the drive automatically. On Solaris machines, ZFS also enables the disk's write cache.

If you partition it manually, you should set your I/O scheduler to no-op so it doesn't conflict with the ZFS scheduler. Partitioning manually also gives you the advantage of putting your /boot outside the ZFS pool so that you can use a bootloader that doesn't support booting from ZFS.

Whole Disk

This is the easiest method and the recommended method.
First lets make sure that the disk is completely wiped from any previous disk labels and partitions. We will also assume that /dev/sda is the target drive.

# gdisk /dev/sda
Command: x ↵
Expert command: z ↵
About to wipe out GPT on /dev/sda. Proceed?: y ↵
GPT data structures destroyed! You may now partition the disk using fdisk or other utilities.
Blank out MBR?: y ↵

This is a destructive operation. Make sure you really don't want anything on this disk.

Now that we have a clean drive, we will create the new pool in it while letting zfs automatically partition it.Create the pool as normal

# zpool create -f -o ashift=12 -o cachefile= -O compression=on -m none -R /mnt/funtoo rpool /dev/sda

Doing this will let ZFS create a GPT style disk with two partitions. We will also slightly modify this to add a BIOS Boot Partition so that grub can be installed successfully. First lets export the pool so that the kernel can use the new partition table without rebooting.

# zpool export rpool

And now lets create a new BIOS Boot Partition at partition 2 from sectors 48 to 2047:

# gdisk /dev/sdaGPT fdisk (gdisk) version 0.8.5Partition table scan:  MBR: protective  BSD: not present  APM: not present  GPT: presentFound valid GPT with protective MBR; using GPT.Command (? for help): ##i##p ↵Disk /dev/sda: 16777216 sectors, 8.0 GiBLogical sector size: 512 bytesDisk identifier (GUID): 09DA0F98-A486-424F-A87D-B3B409381428Partition table holds up to 128 entriesFirst usable sector is 34, last usable sector is 16777182Partitions will be aligned on 2048-sector boundariesTotal free space is 4029 sectors (2.0 MiB)Number  Start (sector)    End (sector)  Size       Code  Name   1            2048        16758783   8.0 GiB     BF01  zfs   9        16758784        16775167   8.0 MiB     BF07 Command (? for help): ##i##n ↵Partition number (2-128, default 2): ##i##↵First sector (34-16777182, default = 16775168) or {+-}size{KMGTP}: ##i##48 ↵Last sector (48-2047, default = 2047) or {+-}size{KMGTP}: ##i## ↵Current type is 'Linux filesystem'Hex code or GUID (L to show codes, Enter = 8300): ##i##EF02 ↵Changed type of partition to 'BIOS boot partition'Command (? for help): ##i##w ↵Final checks complete. About to write GPT data. THIS WILL OVERWRITE EXISTINGPARTITIONS!!Do you want to proceed? (Y/N): ##i##yOK; writing new GUID partition table (GPT) to /dev/sda.The operation has completed successfully.

If you were to check gdisk /dev/sda again, you would see these 3 partitions:

Number  Start (sector)    End (sector)  Size       Code  Name   1            2048        16758783   8.0 GiB     BF01  zfs   2              48            2047   1000.0 KiB  EF02  BIOS boot partition   9        16758784        16775167   8.0 MiB     BF07

Let's import the pool again:

# zpool import -f -o cachefile= -R /mnt/funtoo rpool

Now continue with creating your datasets.=== Manual partitioning ======= fdisk (MBR Style) ====Create Partition 1 (boot):

Command: n ↵Partition type: ##i##↵Partition number: ##i##↵First sector: ##i##↵Last sector: ##i##+250M ↵

Create Partition 2 (ZFS):

Command: n ↵Partition type: ##i##↵Partition number: ##i##↵First sector: ##i##↵Last sector: ##i##↵Command: ##i##t ↵Partition number: ##i##2 ↵Hex code (type L to list codes): ##i##bf ↵Command: ##i##p ↵Disk /dev/sda: 1000.2 GB, 1000204886016 bytes255 heads, 63 sectors/track, 121601 cylinders, total 1953525168 sectorsUnits = sectors of 1 * 512 = 512 bytesSector size (logical/physical): 512 bytes / 512 bytesI/O size (minimum/optimal): 512 bytes / 512 bytesDisk identifier: 0x3e954df7   Device Boot      Start         End      Blocks   Id  System/dev/sda1            2048      514047      256000   83  Linux/dev/sda2          514048  1953525167   976505560   bf  Solaris

==== gdisk (GPT Style) ====Create Partition 1 (boot):

Command: n ↵Partition Number: ##i##↵First sector: ##i##↵Last sector: ##i##+250M ↵Hex Code: ##i##↵

Create Partition 2 (BIOS Boot Partition):

Command: n ↵Partition Number: ##i##↵First sector: ##i##↵Last sector: ##i##+32M ↵Hex Code: ##i##EF02 ↵

Only make the above BIOS Boot Partition if you are using GRUB 2 on GPT. If you are using the extlinux bootloader, this partition is not necessary. The below instructions continue as if you did not create this partition and assumes you are using extlinux as the bootloader.

Create Partition 2 (ZFS):

Command: n ↵Partition Number: ##i##↵First sector: ##i##↵Last sector: ##i##↵Hex Code: ##i##bf01 ↵Command: ##i##p ↵Disk /dev/sda: 1953525168 sectors, 931.5 GiBLogical sector size: 512 bytesDisk identifier (GUID): C0C1E56A-B24F-492F-95DB-2E227676F228Partition table holds up to 128 entriesFirst usable sector is 34, last usable sector is 1953525134Partitions will be aligned on 2048-sector boundariesTotal free space is 2014 sectors (1007.0 KiB)Number  Start (sector)    End (sector)  Size       Code  Name   1            2048          514047   250.0 MiB   8300  Linux filesystem   2          514048      1953525134   931.3 GiB   BF01  Solaris /usr & Mac ZFSCommand: ##i##w ↵

=== Format your boot volume ===

# mkfs.ext4 /dev/sda1

=== Create the zpool ===We will first create the pool. The pool will be named `rpool` and the disk will be aligned to 4096 (using ashift=12)

# zpool create -f -o ashift=12 -o cachefile= -O compression=on -m none -R /mnt/funtoo rpool /dev/sda2

If you followed the GPT partitioning instructions, you should change /dev/sda2 to /dev/sda3.

If you have a previous pool that you would like to import, you can do a: zpool import -R /mnt/funtoo -f <pool_name>

=== Create the zfs datasets ===We will now create some datasets. For this installation, we will create a small but future proof amount of datasets. We will have a dataset for the OS (/), and your swap. We will also show you how to create some optional datasets: /home, /var, /usr/src, and /usr/portage.

Create some empty containers for organization purposes, and make the dataset that will hold /# zfs create -o mountpoint=none rpool/ROOT# ##i##zfs create -o mountpoint=/ rpool/ROOT/funtooOptional, but recommended datasets: /home, /root # ##i##zfs create -o mountpoint=/home rpool/HOME# ##i##zfs create -o mountpoint=/root rpool/HOME/rootOptional datasets: /usr/src, /var# ##i##zfs create -o mountpoint=none rpool/FUNTOO# ##i##zfs create -o mountpoint=/usr/src rpool/FUNTOO/src# ##i##zfs create -o mountpoint=/var rpool/FUNTOO/var

==== Creating a separate portage dataset (optional) ====Creating a separate portage dataset could be useful if you would like to keep your portage tree, distfiles (source code files), and packages (your compiled binaries if you have FEATURES="buildpkg" enabled) in a safe place (or if you want to back up this directory up easily).This requires a few extra steps because we can't just do a regular emerge --sync when we initially chroot. We will need to download a portage snapshot tarball and extract it into the directory.The required steps for getting and extracting the snapshot will be shown later on in the guide once you chroot into the environment. For now just create the datasets:

# zfs create -o mountpoint=/usr/portage -o compression=off rpool/FUNTOO/portage# ##i##zfs create -o mountpoint=/usr/portage/distfiles -o compression=off rpool/FUNTOO/distfiles

=== Create your swap zvol ===Make your swap +1G greater than your RAM. An 8G machine would have 9G of RAM (This is kinda big though).Be warned - zfs is memory hungry. Specially when used with compression=on. A machine with just 4GB can come in troubles while compiling big packages and/or a graphical desktop running. You definitly should have swap running.

# zfs create -o sync=always -o primarycache=metadata -o secondarycache=none -V 9G rpool/swap

=== Format your swap zvol ===

# mkswap -f /dev/zvol/rpool/swap# ##i##swapon /dev/zvol/rpool/swap

Alright that finishes the creation of the zpool and zfs datasets. Check to make sure everything appears fine:

# zpool status# ##i##zfs list

Copy the zpool.cache file to your new environment.

# mkdir -p /mnt/funtoo/etc/zfs# ##i##cp /etc/zfs/zpool.cache /mnt/funtoo/etc/zfs

Make an empty mtab file

# touch /mnt/funtoo/etc/mtab

Now we will continue to install funtoo.== Installing Funtoo ==Download and install the Funtoo stage3 and continue installation as normal.Then chroot into your new funtoo environment:

# cd /mnt/funtooMount your boot drive ** You don't need to do this if you're using whole-disk zfs **# ##i##mount /dev/sda1 /mnt/funtoo/bootBind the kernel related directories# ##i##mount --bind /proc ./proc# ##i##mount --bind /dev ./dev# ##i##mount --bind /sys ./sysCopy network settings# ##i##cp /etc/resolv.conf etc/chroot into your new funtoo environment# ##i##env -i HOME=/root TERM=$TERM chroot . bash -l

=== Syncing your portage tree ======= If you didn't create a separate portage dataset, then just sync your portage tree as normal. ====

# emerge --sync

==== If you did create a separate portage dataset, let's now get the portage snapshot set up. ====

Change into your /usr directory# cd /usrDownload and extract the portage snapshot# ##i##wget http://ftp.osuosl.org/pub/funtoo/funtoo-current/snapshots/portage-latest.tar.xz# ##i##tar xf portage-latest.tar.xzChange into your portage directory and checkout the funtoo branch# ##i##cd portage# ##i##git checkout funtoo.orgNow sync your portage tree# ##i##emerge --sync

== Kernel Configuration ==

The below configurations are the requirements for "Bliss Initramfs Creator". Some of these might not be needed for genkernel.

Tested with kernel 2.6.32, 3.2.34, 3.6.9, 3.7.[1-3].When you get up to the kernel, make sure that you disable the CFQ scheduler, and turnon No-op (It's the default one once you disable all schedulers). The reason for this is because ZFS has itsown scheduler and the CFQ one conflicts with it.Go to your kernel config, and make sure you have the following: (there should be a /usr/src/linux symlink as well)

ZLIB_INFLATE/DEFLATE must be compiled into the kernel (not as a module).> ZLIB_INFLATE [=y], ZLIB_DEFLATE [=y]General setup --->> [*] Initial RAM filesystem and RAM disk (initramfs/initrd) support> () Initramfs source file(s)[*] Enable loadable module support --->[*] Module unloadingEnable the block layer --->IO Schedulers --->< > Deadline I/O scheduler< > CFQ I/O schedulerDefault I/O scheduler (No-op)Device Drivers --->> Generic Driver Options --->>> [*] Maintain a devtmpfs filesystem to mount at /dev>> [*] Automount devtmpfs at /dev, after the kernel mounted the rootfsCryptographic API ---><*> Deflate compression algorithm<*> Zlib compression algorithm* All other drivers required to see your PATA/SATA drives must be compiled in.

Continue and compile/install your kernel:

# make bzImage modules# ##i##make install# ##i##make modules_install

== Installing the ZFS userspace tools ==

# emerge -av zfs

Check to make sure that the zfs tools are working, the zpool.cache file that you copied before should be displayed.

# zpool status# ##i##zfs list

If everything worked, continue.== Install the bootloader ===== GRUB 2 ===If you are using whole-disk zfs then you will need grub2 because grub2 is the only bootloader that supports booting from a zfs pool.Before you do this, make sure this checklist is followed:- Installed kernel and kernel modules- Installed zfs package from the tree- /dev, /proc, /sys are mounted in the chroot environmentOnce all this is good, let's install grub2. First we need to enable the "libzfs" use flag so zfs support is compiled for grub2.

# echo "sys-boot/grub libzfs" >> /etc/portage/package.use

Then we will compile grub2 (GRUB 2 should be _at least_ version 2.0.0 since 2.0.0 added zfs support. 1.99,.98 will not work):

# emerge -av grub

Once this is done, you can check that grub2 is version 2.00 by doing the following command:

# grub-install --versiongrub-install (GRUB) 2.00

Now try to install grub2:

# grub-install --no-floppy /dev/sda

You should receive the following message:

Installation finished. No error reported.

If not, then go back to the above checklist.=== Extlinux ===There are four things we need to do for extlinux:
1. Install extlinux bootloader
2. Write the .bin to the front of the target disk
3. Toggle BIOS partition flag
4. Write a extlinux configuration fileFirst emerge extlinux:

# emerge -av syslinux

Then create a /boot/extlinux directory

# cd /boot# ##i##mkdir /boot/extlinux

Change into the extlinux dir and install the bootloader

# cd /boot/extlinux# ##i##extlinux --install .

==== MBR ====

# fdisk /dev/sdaCommand: ##i##a ↵Partition number: ##i##1 ↵Command: ##i##w ↵

Printing the fdisk partition layout should show a star next to /dev/sda1

/dev/sda   *    2048    514047    256000    83    Linux

Flash the .bin to the front of the disk

# dd conv=notrunc bs=440 count=1 if=/usr/share/syslinux/mbr.bin of=/dev/sda

=== GPT ===

# sgdisk /dev/sda --attributes=1:set:2

Flash the .bin to the front of the disk

# dd conv=notrunc bs=440 count=1 if=/usr/share/syslinux/gptmbr.bin of=/dev/sda

We will write the extlinux/grub configuration file in the next section.== Create the initramfs ==There are two ways to do this, you can use genkernel, or you can use my bliss initramfs creator. I willshow you both.=== genkernel ===

# emerge -av sys-kernel/genkernel# ##i##genkernel --zfs initramfs

Example: kernel name is: vmlinuz-3.7.3-ALLinitramfs name is: initramfs-genkernel-x86_64-3.7.3-ALLpool name is: rpool

grub.cfg:

set timeout=3set default=0# Funtoomenuentry "Funtoo - 3.7.3" {  insmod zfs  linux /ROOT/funtoo/@/boot/vmlinuz-3.7.3-ALL root=rpool/ROOT/funtoo real_root=ZFS=rpool/ROOt/funtoo dozfs=force  initrd /ROOT/funtoo/@/boot/initramfs-genkernel-x86_64-3.7.3-ALL}

extlinux.conf:

LABEL funtoo  MENU LABEL Funtoo 3.7.3-ALL  KERNEL /boot/vmlinuz-3.7.3-ALL  INITRD /boot/initramfs-genkernel-x86_64-3.7.3-ALL  APPEND real_root=ZFS=rpool/ROOT/funtoo dozfs=force

=== Bliss Initramfs Creator ===Clone my creator which is located at: git://github.com/fearedbliss/Bliss-Initramfs-Creator.git

# git clone git://github.com/fearedbliss/Bliss-Initramfs-Creator.git

Then go into this new directory, run the script as root, and place it into /boot

# cd Bliss-Initramfs-Creator# ##i##./createInit# ##i##mv initrd-<kernel_name>.img /boot

<kernel_name> is the name of what you selected in the initramfs creator, and the name of the outputted file.Once you do this just go to your bootloader config, and add it in there.

Example:Kernel name is: vmlinuz-3.7.3-ALLinitramfs name is: initrd-3.7.3-ALL.imgPool root is: rpool/ROOT/funtoo

grub.cfg:

set timeout=3set default=0# Funtoomenuentry "Funtoo - 3.7.3" {  insmod zfs  linux /ROOT/funtoo/@/boot/vmlinuz-3.7.3-ALL root=rpool/ROOT/funtoo quiet  initrd /ROOT/funtoo/@/boot/initrd-3.7.3-ALL.img}

extlinux.conf:

LABEL funtoo  MENU LABEL Funtoo 3.7.1-ALL  KERNEL /boot/vmlinuz-3.7.1-ALL  INITRD /boot/initrd-3.7.1-ALL.img  APPEND pool_root=rpool/ROOT/funtoo

== Final configuration ===== Add the zfs tools to openrc ===

# rc-update add zfs boot

=== Add filesystems to /etc/fstab ===

# nano /etc/fstab# <fs>                  <mountpoint>    <type>          <opts>          <dump/pass># Do not add the /boot line below if you are using whole-disk zfs/dev/sda1               /boot           ext4            defaults        1 2/dev/zvol/rpool/swap    none            swap            sw              0 0

=== Clean up and reboot ===We are almost done, we are just going to clean up, set our root password, and unmount whatever we mounted and get out.

Delete the stage3/portage tarballs you downloaded earlier so they don't take up space.# cd /# ##i##rm stage3-latest.tar.xz# ##i##rm /usr/portage-latest.tar.xzSet your root password# ##i##passwd>> Enter your password, you won't see what you are writing (for security reasons), but it is there!Get out of the chroot environment# ##i##exitUnmount all the kernel filesystem stuff and boot# ##i##cd /mnt/funtoo# ##i##umount proc dev sys bootTurn off the swap# ##i##swapoff /dev/zvol/rpool/swapExport the zpool# ##i##cd /# ##i##zpool export -f rpoolReboot# ##i##reboot

Don't forget to set your root password as stated above before exiting chroot and rebooting. If you don't set the root password, you won't be able to log into your new system.

and that should be enough to get your system to boot on ZFS.== Extra: After reboot ==After you restart your machine and your inside your desktop, continue to set up anything you need in terms of /etc configurations. Once you have everything the way you like it, take a snapshot of your system. You will be using this snapshot to revert back to this state if anything ever happens to your system down the road. The snapshots are cheap, and almost instant. To take the snapshot of your rootfs, type the following:

# zfs snapshot rpool/ROOT/funtoo@install

To see if your snapshot was taken, type:

# zfs list -t snapshot

If your machine ever fails and you need to get back to this state, just type:

# zfs rollback rpool/ROOT/funtoo@install

=== Recovery Environment ===On ZFS it is extremely easy to create a recovery environment using an already working snapshot. So that's what we will be doing. Create a clone of the @install snapshot which you will use for recovery purposes. If something happens to your main install, you can boot into this clone and fix the main one. One of the differences (maybe the only difference) between a clone and a snapshot is that a clone is rewritable while a snapshot is only read-only.

# zfs clone rpool/ROOT/funtoo@install rpool/ROOT/recovery

==== Add the clone to your extlinux.conf ====

LABEL funtoo-recovery    MENU LABEL Funtoo Recovery    KERNEL /boot/vmlinuz-3.7.1-ALL    INITRD /boot/initrd-3.7.1-ALL.img    APPEND pool_root=rpool/ROOT/recovery

==== Things to watch out for ====Since your recovery clone will tend to get old as you use your main system, and since your recovery and other stuff are on the same pool, we don't want the new pool stuffto be mounted when we launch recovery. We also don't want video drivers to beconflicting.1. Make sure that nvidia/nouveau stuff are blacklisted.2. Make sure that your /boot and /lib/modules for the kernel in your 'recovery' arematching.3. Disable the zfs openrc script so that nothing else gets automatically mounted.Only your rootfs.You can do the above stuff by mounting your copy and chrooting into it.

Mount the recovery clone# mkdir /mnt/recovery# ##i##mount -t zfs -o zfsutil rpool/ROOT/recovery /mnt/recovery# ##i##cd /mnt/recoveryMount the kernel devices# ##i##mount --bind /proc ./proc# ##i##mount --bind /dev ./dev# ##i##mount --bind /sys ./sysCopy zpool.cache# ##i##cp /etc/zfs/zpool.cache etc/zfsChroot into the new environment# ##i##env -i HOME=/root TERM=$TERM chroot . bash --loginDisable zfs/zfs-shutdown openrc scripts# ##i##rc-config delete zfs bootBlacklist nouveau/nvidia drivers# ##i##echo "blacklist nouveau" >> /etc/modprobe.d/blacklist.conf# ##i##echo "blacklist nvidia" >> /etc/modprobe.d/blacklist.conf

==== Getting into the recovery ====Just start your machine and pick the Funtoo Recovery option from the Boot Menu.Enjoy your new install on ZFS :)