Difference between pages "Funtoo Linux Kernels" and "ZFS Install Guide"

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(Installing the ZFS userspace tools and kernel modules)
 
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This Section will give you an overview of kernels used in funtoo.
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== Introduction ==
  
Funtoo Linux provides a number of new kernels for your use. This is the official page for all Funtoo Linux kernel information.  
+
This tutorial will show you how to install Funtoo on ZFS (rootfs). This tutorial is meant to be an "overlay" over the [[Funtoo_Linux_Installation|Regular Funtoo Installation]]. Follow the normal installation and only use this guide for steps 2, 3, and 8.
  
Some points of interest:
+
=== Introduction to ZFS ===
  
* Most Funtoo Linux kernels support the handy <tt>[[#Binary USE|binary]]</tt> USE flag, described below.
+
Since ZFS is a new technology for Linux, it can be helpful to understand some of its benefits, particularly in comparison to BTRFS, another popular next-generation Linux filesystem:
* Funtoo Linux offers quality kernels from other Linux Distributions, like <tt>ubuntu-server</tt> and <tt>debian-sources</tt>.
+
* A detailed [[#Kernel Features and Stability|Kernel Features and Stability]] table can be found below.
+
* Advanced users may want to take a look at [[Additional Kernel Resources]].
+
* There is a quick'n dirty howto to compile your own [[kernel]] with initramfs the funtoo way.
+
  
== Overview of Kernels ==
+
* On Linux, the ZFS code can be updated independently of the kernel to obtain the latest fixes. btrfs is exclusive to Linux and you need to build the latest kernel sources to get the latest fixes.
  
=== sysrescue-std-sources ===
+
* ZFS is supported on multiple platforms. The platforms with the best support are Solaris, FreeBSD and Linux. Other platforms with varying degrees of support are NetBSD, Mac OS X and Windows. btrfs is exclusive to Linux.
  
This kernel is from the [http://www.sysresccd.org SystemRescueCD project], and is based on Fedora 14/15, plus some other patches related to booting from a live CD. It is a quality kernel, and is generally pretty stable. It is not suitable for production servers but is a good choice for Funtoo Linux desktops. Earlier,the [[Funtoo Linux Installation]] Guide recommended this kernel for general users, but now 'debian-sources' is recommended. Note however, that by design all audio functions are removed from SystemRescue,  ie no sound when using this kernel.
+
* ZFS has the Adaptive Replacement Cache replacement algorithm while btrfs uses the Linux kernel's Last Recently Used replacement algorithm. The former often has an overwhelmingly superior hit rate, which means fewer disk accesses.
  
=== vanilla-sources ===
+
* ZFS has the ZFS Intent Log and SLOG devices, which accelerates small synchronous write performance.
  
This will install the "vanilla" (unmodified) Linux kernel sources. Current recommended version is 3.x. Funtoo Linux fully supports Linux 3.x. The advantages of this kernel include recent improvements to [[Linux Containers]], a very modern networking stack with lots of bug fixes, and high reliability for desktops and servers. The downside is that this kernel must be manually configured by the user and does not have built-in <tt>genkernel</tt> support via the <tt>binary</tt> USE flag at this time.
+
* ZFS handles internal fragmentation gracefully, such that you can fill it until 100%. Internal fragmentation in btrfs can make btrfs think it is full at 10%. Btrfs has no automatic rebalancing code, so it requires a manual rebalance to correct it.
  
=== gentoo-sources ===
+
* ZFS has raidz, which is like RAID 5/6 (or a hypothetical RAID 7 that supports 3 parity disks), except it does not suffer from the RAID write hole issue thanks to its use of CoW and a variable stripe size. btrfs gained integrated RAID 5/6 functionality in Linux 3.9. However, its implementation uses a stripe cache that can only partially mitigate the effect of the RAID write hole.
  
This kernel tree is based on stable kernels from [https://www.kernel.org/ kernel.org] with genpatches applied [http://dev.gentoo.org/~mpagano/genpatches/about.htm genpatches].
+
* ZFS send/receive implementation supports incremental update when doing backups. btrfs' send/receive implementation requires sending the entire snapshot.
Gentoo patchset aims to support the entire range of Gentoo-supported architectures. List of available genpatched kernels: [http://dev.gentoo.org/~mpagano/genpatches/kernels.htm genpatches-kernels]
+
  
=== openvz-rhel6-stable ===
+
* ZFS supports data deduplication, which is a memory hog and only works well for specialized workloads. btrfs has no equivalent.
  
This is a RHEL6-based kernel with OpenVZ support. This kernel is now the preferred kernel for production OpenVZ deployments. It requires gcc-4.4.5 to build, which it will use automatically without the user needing to use <tt>gcc-config</tt>. We use this version of gcc since this is the version of gcc used by Red Hat to build this kernel.
+
* ZFS datasets have a hierarchical namespace while btrfs subvolumes have a flat namespace.
  
=== openvz-rhel5-stable ===
+
* ZFS has the ability to create virtual block devices called zvols in its namespace. btrfs has no equivalent and must rely on the loop device for this functionality, which is cumbersome.
  
This kernel is based on the latest Red Hat Enterprise Linux 5.6 kernel, and contains additional OpenVZ (virtual containers) patches from the [[OpenVZ on Funtoo Linux|OpenVZ]] project. It is a very stable and reliable kernel, and is recommended for use in production environments. The only major downside to this kernel is that it is based on Linux 2.6.18 -- some parts of the kernel are out-of-date, and it is not compatible with modern versions of udev. However, it is pretty trivial to downgrade udev to an earlier version on Funtoo Linux and this kernel has a track-record of being rock-solid. When stability is paramount, you put up with the udev downgrade, use this kernel, and can enjoy hundreds of days of uptime. For more information on how to use this kernel with Funtoo Linux, see the [[RHEL5 Kernel HOWTO]].
+
The only area where btrfs is ahead of ZFS is in the area of small file
 +
efficiency. btrfs supports a feature called block suballocation, which
 +
enables it to store small files far more efficiently than ZFS. It is
 +
possible to use another filesystem (e.g. reiserfs) on top of a ZFS zvol
 +
to obtain similar benefits (with arguably better data integrity) when
 +
dealing with many small files (e.g. the portage tree).
  
=== ubuntu-server ===
+
=== Disclaimers ===
  
This is the kernel from Ubuntu Server. Version <tt>2.6.32.32.62</tt> is the same version used in Ubuntu Server 10.04 LTS, and version <tt>2.6.35.28.50</tt> is the one used in Ubuntu Server 10.10 (currently masked). In our testing of <tt>2.6.32.32.62</tt>, it has been very reliable and offers very good performance. One exception, which is common among 2.6.32-based kernels, is that it's recommended that you emerge <tt>broadcom-netxtreme2</tt> if you have any Broadcom-based NICs, as the in-kernel drivers have compatibility issues with certain models. This kernel is a very good option if you want a relatively modern server kernel and do not need [[OpenVZ]] support. We use gcc-4.4.5 to build this kernel. It will use gcc-4.4.5 automatically, without requiring the user to use <tt>gcc-config</tt>.
+
{{fancywarning|This guide is a work in progress. Expect some quirks.}}
 +
{{fancyimportant|'''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'''!}}
  
=== debian-sources ===
+
== Video Tutorial ==
  
This is the Debian kernel. '''These ebuilds now support the <tt>binary</tt> USE flag.''' Daniel has added a special <tt>config-extract</tt> command which can be used to list all available official Debian kernel configurations, and generate them from the Debian files included with the kernel. This kernel has optional [[OpenVZ]] support, but it is much better to use <tt>openvz-rhel6-stable</tt> if you want a production-quality OpenVZ installation. For more information about how to use <tt>debian-sources</tt> and <tt>config-extract</tt>, see [[#Using Debian-Sources with Genkernel|Using debian-sources with Genkernel]] below.
+
As a companion to the install instructions below, a YouTube video ZFS install tutorial is now available:
  
=== debian-sources-lts ===
+
{{#widget:YouTube|id=kxEdSXwU0ZI|width=640|height=360}}
  
This is the Debian long-term stable kernel. '''These ebuilds now support the <tt>binary</tt> USE flag.''' Daniel has added a special <tt>config-extract</tt> command which can be used to list all available official Debian kernel configurations, and generate them from the Debian files included with the kernel.
+
== Downloading the ISO (With ZFS) ==
 
+
In order for us to install Funtoo on ZFS, you will need an environment that provides the ZFS tools. Therefore we will download a customized version of System Rescue CD with ZFS already included. When booting, use the "alternate"-kernel. The ZFS-module won't work with the default kernel.  
== Binary USE ==
+
 
+
Many of the kernel ebuilds in Funtoo Linux support the very useful <tt>binary</tt> USE flag. By enabling this USE flag and emerging the kernel, the ebuild will automatically build a binary kernel image, initramfs and kernel modules and install them to <tt>/boot</tt>. The binary kernel image and initramfs can be used to boot your Funtoo Linux system without requiring any additional configuration. This is a great way to get a Funtoo Linux system up and running quickly. Here's how to do it:
+
  
 
<pre>
 
<pre>
# echo "sys-kernel/openvz-rhel5-stable binary" >> /etc/portage/package.use
+
Name: sysresccd-4.0.0_zfs_0.6.2.iso  (522 MB)
# emerge openvz-rhel5-stable
+
Release Date: 2014-01-18
# nano -w /etc/boot.conf
+
md5sum 5a6530088e63b516765f78076a2e4859
# boot-update
+
 
</pre>
 
</pre>
  
More information can be found in the [[Funtoo Linux Installation]] Guide.
 
  
== Funtoo Linux Genkernel ==
+
'''[http://ftp.osuosl.org/pub/funtoo/distfiles/sysresccd/ Download System Rescue CD with ZFS]'''<br />
  
Funtoo Linux contains a forked/enhanced version of genkernel with the following new capabilities:
+
== Creating a bootable USB from ISO ==
 +
After you download the iso, you can do the following steps to create a bootable USB:
  
* genkernel can use a build directory that is separate from the kernel source directory. This is enabled using the new <tt>--build-dst</tt> option.
+
<console>
* <tt>--build-src</tt> is a new option that is equivalent to the <tt>--kerneldir</tt> option.
+
Make a temporary directory
* <tt>--fullname</tt> can be used to specify the entire name of the kernel and initramfs images -- everything after <tt>kernel-</tt> and <tt>initramfs-</tt>.
+
# ##i##mkdir /tmp/loop
* <tt>--firmware-src</tt> - a new option that works identically to <tt>--firmware-dir</tt>.
+
* <tt>--firmware-dst</tt> - a new capability - you can now define where genkernel installs firmware.
+
* Genkernel uses Funtoo Linux <tt>lvm2</tt> rather than building its own.
+
* Some compile fixes.
+
  
== Kernel Features and Stability ==
+
Mount the iso
 +
# ##i##mount -o ro,loop /root/sysresccd-4.0.0_zfs_0.6.2.iso /tmp/loop
  
This page provides an overview of kernel features and stability information:
+
Run the usb installer
 +
# ##i##/tmp/loop/usb_inst.sh
 +
</console>
  
{| {{table}}
+
That should be all you need to do to get your flash drive working.
!Kernel Name
+
!Version
+
!USE flags
+
!Stability
+
!Extra Features
+
!Req'd udev
+
!Notes
+
|-
+
|<tt>[[#vanilla-sources|vanilla-sources]]</tt>
+
|3.11.4
+
|N/A
+
|'''Excellent''' - recommended for desktops and servers.
+
|N/A
+
|Any
+
|Recommended for modern networking stack, hardware and [[Linux Containers]] support. This kernel must be manually configured by the user. New Features: [http://kernelnewbies.org/Linux_3.11 kernelnewbies.org/linux_3.11]  New Drivers: [http://kernelnewbies.org/Linux_3.11-DriversArch kernelnewbies/Linux_3.11-DriversArch]
+
|-
+
|<tt>[[#gentoo-sources|gentoo-sources]]</tt>
+
|3.11.4
+
|N/A
+
|'''Excellent''' - recommended for desktops and workstations
+
|N/A
+
|Any
+
|Recommended for modern networking stack, hardware and [[Linux Containers]] support. This kernel must be manually configured by the user. New Features: [http://kernelnewbies.org/Linux_3.11 kernelnewbies.org/linux_3.11]  New Drivers: [http://kernelnewbies.org/Linux_3.11-DriversArch kernelnewbies/Linux_3.11-DriversArch]
+
|-
+
|<tt>[[#sysrescue-std-sources|sysrescue-std-sources]]</tt>
+
|3.0.21.302
+
|<tt>binary</tt>
+
|''Good'' - recommended for desktops
+
|N/A
+
|Any
+
|Nvidia card users: binary use flag installs nouveau drivers. Not compatible with nvidia-drivers.
+
|-
+
|<tt>[[#openvz-rhel6-stable|openvz-rhel6-stable]]</tt>
+
|2.6.32.042.079.5
+
|<tt>binary</tt>
+
|'''Excellent''' - recommended for production servers
+
|N/A
+
|Any
+
|This kernel is built with gcc-4.4.5. <tt>emerge broadcom-netxtreme2</tt> for reliable BCM5709+ support (integrated NIC)
+
|-
+
|<tt>[[#openvz-rhel5-stable|openvz-rhel5-stable]]</tt>
+
|2.6.18.028.095.1
+
|<tt>binary</tt>
+
|'''Excellent''' - recommended for production servers
+
|OpenVZ
+
|=sys-fs/udev-146*
+
|Broadcom <tt>bnx2</tt> driver module bundled with kernel appears to be OK. This kernel is built with gcc-4.1.2. Enabling the <tt>binary</tt> USE flag will cause gcc-4.1.2 to be emerged and used for building the kernel.
+
|-
+
|<tt>[[#ubuntu-server|ubuntu-server]]</tt>
+
|2.6.32.32.62
+
|<tt>binary</tt>
+
|'''Excellent''' - recommended for production servers (still in extended testing)
+
| N/A
+
|Any
+
|This kernel is built with gcc-4.4.5. <tt>emerge broadcom-netxtreme2</tt> for reliable BCM5709+ support (integrated NIC)
+
|-
+
|<tt>[[#ubuntu-server|ubuntu-server]]</tt>
+
|2.6.35.28.50
+
|<tt>binary</tt>
+
|''not yet tested''
+
| N/A
+
|Any
+
|This kernel is built with gcc-4.4.5. <tt>emerge broadcom-netxtreme2</tt> for reliable BCM5709+ support (integrated NIC)
+
|-
+
|<tt>[[#debian-sources|debian-sources]]</tt>
+
|3.10.11
+
|<tt>openvz</tt>
+
|''Good'' - default kernel recommended by Funtoo
+
|OpenVZ (optional)
+
|Any
+
|See [[#Using debian-sources with Genkernel]], below.
+
|-
+
|}
+
  
== Using Debian-Sources with Genkernel ==
+
When you are booting into system rescue cd, make sure you select the '''alternative 64 bit kernel'''. ZFS support was specifically added to the alternative 64 bit kernel rather than the standard 64 bit kernel.
  
{{ fancyimportant|Debian-sources is now fully compatible with ''binary'' USE flag and recommended for desktop users. The below example is valid for manual installation. At least 12G of /var/tmp required to build
+
== 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.
This section describes how to build a binary kernel with <tt>debian-sources</tt> and <tt>genkernel</tt>, and it also explains how to use Funtoo Linux's <tt>config-extract</tt> tool to list and create official Debian kernel configurations.
+
  
=== First step: emerging the required packages ===
+
We will be showing you how to partition it '''manually''' because if you partition it manually you get to create your own layout, you get to have your own separate /boot partition (Which is nice since not every bootloader supports booting from ZFS pools), and you get to boot into RAID10, RAID5 (RAIDZ) pools and any other layouts due to you having a separate /boot partition.
  
The first step is to emerge:
+
==== gdisk (GPT Style) ====
  
# The Debian sources
+
'''A Fresh Start''':
# Genkernel itself
+
  
This is achieved with:
+
First lets make sure that the disk is completely wiped from any previous disk labels and partitions.
 +
We will also assume that <tt>/dev/sda</tt> is the target drive.<br />
  
<pre>
+
<console>
# emerge sys-kernel/debian-sources sys-kernel/genkernel
+
# ##i##gdisk /dev/sda
</pre>
+
  
Once the Debian kernel sources are deployed, you should find a directory named '''linux-debian-''version''''' (e.g. linux-debian-2.6.32.30) under '''/usr/src'''. Update your the '''linux''' symlink to point on this directory:
+
Command: ##i##x ↵
<pre>
+
Expert command: ##i##z ↵
# cd /usr/src
+
About to wipe out GPT on /dev/sda. Proceed?: ##i##y ↵
# rm linux
+
GPT data structures destroyed! You may now partition the disk using fdisk or other utilities.
# ln -s linux-debian-2.6.32.30 linux
+
Blank out MBR?: ##i##y ↵
</pre>
+
</console>
Alternatively, emerge the debian-sources with USE="symlink"
+
  
=== Second step: Grabbing a configuration file ===
+
{{fancywarning|This is a destructive operation. Make sure you really don't want anything on this disk.}}
  
If is now time to download the kernel configuration file. For this tutorial we will use a configuration file for AMD64 (several others architectures like MIPS or SPARC64 are available.)  To view a complete list of available kernel configurations, type <tt>./config-extract -l</tt> in the Debian kernel source directory:
+
Now that we have a clean drive, we will create the new layout.
  
<pre>
+
'''Create Partition 1''' (boot):
ninja1 linux-debian-2.6.32.30 # ./config-extract -l
+
<console>
 +
Command: ##i##n ↵
 +
Partition Number: ##i##↵
 +
First sector: ##i##↵
 +
Last sector: ##i##+250M ↵
 +
Hex Code: ##i##↵
 +
</console>
  
====== standard featureset ======
+
'''Create Partition 2''' (BIOS Boot Partition):
 +
<console>Command: ##i##n ↵
 +
Partition Number: ##i##↵
 +
First sector: ##i##↵
 +
Last sector: ##i##+32M ↵
 +
Hex Code: ##i##EF02 ↵
 +
</console>
  
      alpha: alpha-generic, alpha-legacy, alpha-smp
+
'''Create Partition 3''' (ZFS):
      amd64
+
<console>Command: ##i##n ↵
      armel: iop32x, ixp4xx, kirkwood, orion5x, versatile
+
Partition Number: ##i##↵
        hppa: parisc, parisc-smp, parisc64, parisc64-smp
+
First sector: ##i##↵
        i386: 486, 686, 686-bigmem, amd64
+
Last sector: ##i##↵
        ia64: itanium, mckinley
+
Hex Code: ##i##bf00 ↵
        m68k: amiga, atari, bvme6000, mac, mvme147, mvme16x
+
        mips: 4kc-malta, 5kc-malta, r4k-ip22, r5k-ip32, sb1-bcm91250a, sb1a-bcm91480b
+
      mipsel: 4kc-malta, 5kc-malta, r5k-cobalt, sb1-bcm91250a, sb1a-bcm91480b
+
    powerpc: powerpc, powerpc-smp, powerpc64
+
        s390: s390x, s390x-tape
+
        sh4: sh7751r, sh7785lcr
+
      sparc: sparc64, sparc64-smp
+
    sparc64: sparc64, sparc64-smp
+
  
====== vserver featureset ======
+
Command: ##i##p ↵
  
      amd64
+
Number  Start (sector)    End (sector)  Size      Code  Name
        i386: 686, 686-bigmem
+
  1            2048          514047  250.0 MiB  8300  Linux filesystem
        ia64: itanium, mckinley
+
  2          514048          579583  32.0 MiB    EF02  BIOS boot partition
     powerpc: powerpc, powerpc64
+
  3          579584     1953525134  931.2 GiB  BF00  Solaris root
        s390
+
      sparc
+
    sparc64
+
  
====== xen featureset ======
+
Command: ##i##w ↵
 +
</console>
  
      amd64
 
        i386
 
  
====== openvz featureset ======
+
=== Format your boot volume ===
 +
Format your separate <tt>/boot</tt> partition:
 +
<console>
 +
# ##i##mkfs.ext2 /dev/sda1
 +
</console>
  
      amd64
+
=== Encryption (Optional) ===
        i386
+
If you want encryption, then create your encrypted vault(s) now by doing the following:
</pre>
+
  
Type <tt>config-extract -h</tt> for extended usage information:
+
<console>
 +
# ##i##cryptsetup luksFormat /dev/sda3
 +
# ##i##cryptsetup luksOpen /dev/sda3 vault_1
 +
</console>
  
<pre>
+
=== Create the zpool ===
ninja1 linux-debian-2.6.32.30 # ./config-extract -h
+
We will first create the pool. The pool will be named `tank` and the disk will be aligned to 4096 (using ashift=12)
This work is free software.
+
<console># ##i##zpool create -f -o ashift=12 -o cachefile= -O compression=on -m none -R /mnt/funtoo tank /dev/sda3</console>
  
Copyright 2011 Funtoo Technologies. You can redistribute and/or modify it under
+
{{fancyimportant|If you are using encrypted root, change '''/dev/sda3 to /dev/mapper/vault_1'''.}}
the terms of the GNU General Public License version 3 as published by the Free
+
Software Foundation. Alternatively you may (at your option) use any other
+
license that has been publicly approved for use with this program by Funtoo
+
Technologies (or its successors, if any.)
+
  
usage: config-extract [options] arch [featureset] [subarch]
+
{{fancynote| '''ashift<nowiki>=</nowiki>12''' should be use if you have a newer, advanced format disk that has a sector size of 4096 bytes. If you have an older disk with 512 byte sectors, you should use '''ashift<nowiki>=</nowiki>9''' or don't add the option for auto detection.}}
  
  ---help        print this usage and exit
+
{{fancynote| If you have a previous pool that you would like to import, you can do a: '''zpool import -f -R /mnt/funtoo <pool_name>'''.}}
  -l  --list        list all available kernel configurations
+
  -o  --outfile    specify kernel config outfile --
+
                    defaults to .config in current directory
+
  [featureset]      defaults to "none" if not specified
+
  [subarch]        defaults to the only one available; otherwise required
+
  
This program was written by Daniel Robbins for Funtoo Linux, for the purpose of
+
=== Create the zfs datasets ===
easily and conveniently extracting Debian kernel configurations. To see a nice
+
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: <tt>/home</tt>, <tt>/var</tt>, <tt>/usr/src</tt>, and <tt>/usr/portage</tt>.
list of all available kernel configurations, use the --list option.
+
  
Debian's kernel configs are specified internally in arch_featureset_flavor
+
<console>
format, such as: "amd64_openvz_amd64". The featureset typically describes an
+
Create some empty containers for organization purposes, and make the dataset that will hold /
optional kernel configuration such as "xen" or "openvz", while the flavor in
+
# ##i##zfs create -p tank/os/funtoo
Debian terminology typically refers to the sub-architecture of the CPU.
+
# ##i##zfs create -o mountpoint=/ tank/os/funtoo/root
  
When using this command, you must specify an arch. A featureset of "none" is
+
Optional, but recommended datasets: /home
assumed unless you specify one, and by default this program will pick the only
+
# ##i##zfs create -o mountpoint=/home tank/os/funtoo/home
available subarch if there is only one to choose from. If not, you will need to
+
pick one (and the program will remind you to do this.)
+
  
The kernel configuration will be written to ".config" in the current directory,
+
Optional datasets: /usr/src, /usr/portage/{distfiles,packages}
or the location you specified using the -o/--outfile option.
+
# ##i##zfs create -o mountpoint=/usr/src tank/os/funtoo/src
</pre>
+
# ##i##zfs create -o mountpoint=/usr/portage -o compression=off tank/os/funtoo/portage
 +
# ##i##zfs create -o mountpoint=/usr/portage/distfiles tank/os/funtoo/portage/distfiles
 +
# ##i##zfs create -o mountpoint=/usr/portage/packages tank/os/funtoo/portage/packages
 +
</console>
  
Let's use <tt>config-extract</tt> to create a kernel configuration for an amd64 system:
+
=== Create your swap zvol ===
 +
'''Make your swap +1G greater than your RAM. An 8G machine would have 9G of SWAP (This is kinda big though). For machines with this much memory, You could just make it 2G if you don't have any problems.'''
 +
<console>
 +
# ##i##zfs create -o sync=always -o primarycache=metadata -o secondarycache=none -o volblocksize=4K -V 1G tank/swap
 +
</console>
  
<pre>
+
=== Format your swap zvol ===
# cd linux
+
<console>
# ./config-extract amd64
+
# ##i##mkswap -f /dev/zvol/tank/swap
Wrote amd64_none_amd64 kernel configuration to /usr/src/linux-debian-2.6.32.30/.config.
+
# ##i##swapon /dev/zvol/tank/swap
</pre>
+
</console>
  
<tt>config-extract</tt> also allows you to extract special Debian featuresets, such as settings for Xen and [[OpenVZ]] kernels:
+
Now we will continue to install funtoo.
  
<pre>
+
== Installing Funtoo ==
# ./config-extract amd64 openvz
+
[[Funtoo_Linux_Installation|Download and extract the Funtoo stage3 and continue installation as normal.]]
Wrote amd64_openvz_amd64 kernel configuration to /usr/src/linux-debian-2.6.32.30/.config.
+
</pre>
+
  
'''It is necessary to name the kernel configuration file something other than ".config" to avoid errors with genkernel.'''
+
Then once you've extracted the stage3, chroot into your new funtoo environment:
 +
<console>
 +
Go into the directory that you will chroot into
 +
# ##i##cd /mnt/funtoo
  
 +
Mount your boot drive
 +
# ##i##mount /dev/sda1 /mnt/funtoo/boot
  
After using <tt>config-extract</tt>, run <tt>make oldconfig</tt> and accept all default options by hitting Enter at all prompts.
+
Bind the kernel related directories
 +
# ##i##mount -t proc none /mnt/funtoo/proc
 +
# ##i##mount --rbind /dev /mnt/funtoo/dev
 +
# ##i##mount --rbind /sys /mnt/funtoo/sys
  
=== Third step: Building and installing the kernel ===
+
Copy network settings
 +
# ##i##cp /etc/resolv.conf /mnt/funtoo/etc/
  
This is simply achieved by:
+
chroot into your new funtoo environment
 +
# ##i##env -i HOME=/root TERM=$TERM chroot /mnt/funtoo /bin/bash --login
  
<pre>
+
Place your mountpoints into your /etc/mtab file
# genkernel --kernel-config=config-2.6.32-5-amd64 all
+
# ##i##cat /proc/mounts > /etc/mtab
</pre>
+
 
 +
Sync your tree
 +
# ##i##emerge --sync
 +
</console>
 +
 
 +
=== Add filesystems to /etc/fstab ===
 +
 
 +
Before we continue to compile and or install our kernel in the next step, we will edit the <tt>/etc/fstab</tt> file because if we decide to install our kernel through portage, portage will need to know where is your <tt>/boot</tt> so that it can place the files in there. We also need to update <tt>/etc/mtab</tt> so our system knows what is mounted
 +
 
 +
{{File
 +
|/etc/fstab|<pre>
 +
# <fs>                  <mountpoint>    <type>          <opts>          <dump/pass>
 +
 
 +
/dev/sda1              /boot          ext2            defaults        0 2
 +
/dev/zvol/tank/swap    none            swap            sw              0 0
 +
</pre>}}
 +
 
 +
== Kernel Configuration ==
 +
To speed up this step, you can install "bliss-kernel" since it's already properly configured for ZFS and a lot of other configurations. The kernel is also compiled and ready to go. To install {{Package|sys-kernel/bliss-kernel}} type the following:
 +
 
 +
<console>
 +
# ##i##emerge -av bliss-kernel
 +
</console>
 +
 
 +
Now make sure that your <tt>/usr/src/linux symlink</tt> is pointing to this kernel by typing the following:
 +
<console>
 +
# ##i##eselect kernel list
 +
Available kernel symlink targets:
 +
[1]  linux-3.10.10-FB.01 *
 +
</console>
 +
You should see a star next to the bliss-kernel version you installed. In this case it was 3.10.10-FB.01. If it's not set, you can type '''eselect kernel set #'''.
 +
 
 +
== Installing the ZFS userspace tools and kernel modules ==
 +
Emerge {{Package|sys-fs/zfs}}, {{Package|sys-kernel/spl}}, and {{Package|sys-fs/zfs-kmod}}:
 +
<console># ##i##emerge -av zfs spl zfs-kmod</console>
 +
Check to make sure that the zfs tools are working, the <code>zpool.cache</code> file that you copied before should be displayed.
 +
 
 +
{{Fancynote| SPL stands for: Solaris Porting Layer}}
 +
<console>
 +
# ##i##zpool status
 +
# ##i##zfs list
 +
</console>
 +
 
 +
If everything worked, continue.
 +
 
 +
== Install the bootloader ==
 +
=== GRUB 2 ===
 +
Before you do this, make sure this checklist is followed:
 +
* Installed kernel and kernel modules
 +
* Installed zfs package from the tree
 +
* <code>/dev</code>, <code>/proc</code>, <code>/sys</code> are mounted in the chroot environment
 +
 
 +
Once all this is checked, let's install grub2. First we need to enable the "libzfs" use flag so zfs support is compiled for grub2.
 +
 
 +
<console># ##i##echo "sys-boot/grub libzfs" >> /etc/portage/package.use</console>
 +
 
 +
Then we will compile grub2:
 +
 
 +
<console># ##i##emerge -av grub</console>
 +
 
 +
Once this is done, you can check that grub is version 2.00 by doing the following command:
 +
<console>
 +
# ##i##grub-install --version
 +
grub-install (GRUB) 2.00
 +
</console>
 +
 
 +
Now try to install {{Package|sys-boot/grub}}:
 +
<console>
 +
# ##i##grub-install --recheck /dev/sda
 +
</console>
 +
 
 +
You should receive the following message:
 +
<console>
 +
Installation finished. No error reported.
 +
</console>
 +
 
 +
If not, then go back to the above checklist.
 +
 
 +
=== LILO ===
 +
Before you do this, make sure the following checklist is followed:
 +
* <code>/dev</code>, <tt>/proc</tt> and <tt>/sys</tt> are mounted.
 +
* Installed the {{Package|sys-fs/zfs}} package from the tree.
 +
Once the above requirements are met, LILO can be installed.
 +
 
 +
Now we will install {{Package|sys-boot/lilo}}.
 +
<console># ##i##emerge -av sys-boot/lilo</console>
 +
Once the installation of LILO is complete we will need to edit the lilo.conf file.
 +
{{File
 +
|/etc/lilo.conf|<pre>
 +
boot=/dev/sda
 +
prompt
 +
timeout=4
 +
default=Funtoo
 +
 
 +
image=/boot/bzImage
 +
      label=Funtoo
 +
      read-only
 +
      append="root=tank/os/funtoo/root"
 +
      initrd=/boot/initramfs
 +
</pre>}}
 +
All that is left now is to install the bootcode to the MBR.
 +
 
 +
This can be accomplished by running:
 +
<console># ##i##/sbin/lilo</console>
 +
If it is successful you should see:
 +
<console>
 +
Warning: LBA32 addressing assumed
 +
Added Funtoo + *
 +
One warning was issued
 +
</console>
 +
 
 +
== Create the initramfs ==
 +
There are two ways to do this, you can use genkernel, or you can use my bliss initramfs creator. I will show you both.
 +
 
 +
=== genkernel ===
 +
<console>
 +
# ##i##emerge -av sys-kernel/genkernel
 +
# You only need to add --luks if you used encryption
 +
# ##i##genkernel --zfs --luks initramfs
 +
</console>
 +
 
 +
=== Bliss Initramfs Creator ===
 +
If you are encrypting your drives, then add the "luks" use flag to your package.use before emerging:
 +
 
 +
<console>
 +
# ##i##echo "sys-kernel/bliss-initramfs luks" >> /etc/portage/package.use
 +
</console>
 +
 
 +
Now install the creator:
 +
 
 +
<console>
 +
# ##i##emerge bliss-initramfs
 +
</console>
 +
 
 +
 
 +
Then go into the install directory, run the script as root, and place it into /boot:
 +
<console># ##i##cd /opt/bliss-initramfs
 +
# ##i##./createInit
 +
# ##i##mv initrd-<kernel_name> /boot
 +
</console>
 +
'''<kernel_name>''' is the name of what you selected in the initramfs creator, and the name of the outputted file.
 +
 
 +
== Using boot-update ==
 +
=== /boot on separate partition ===
 +
If you created a separate non-zfs partition for boot then configuring boot-update is almost exactly the same as a normal install except that auto detection for root does not work. You must tell boot-update what your root is.
 +
==== Genkernel ====
 +
If your using genkernel you must add 'real_root=ZFS=<root>' and 'dozfs' to your params.
 +
Example entry for boot.conf:
 +
<console>
 +
"Funtoo ZFS" {
 +
        kernel vmlinuz[-v]
 +
        initrd initramfs-genkernel-x86_64[-v]
 +
        params real_root=ZFS=tank/os/funtoo/root
 +
        params += dozfs=force
 +
        # Also add 'params += crypt_root=/dev/sda3' if you used encryption
 +
        # Adjust the above setting to your system if needed
 +
}
 +
</console>
 +
 
 +
==== Bliss Initramfs Creator ====
 +
If you used the Bliss Initramfs Creator then all you need to do is add 'root=<root>' to your params.
 +
Example entry for boot.conf:
 +
<console>
 +
"Funtoo ZFS" {
 +
        kernel vmlinuz[-v]
 +
        initrd initrd[-v]
 +
        params root=tank/os/funtoo/root quiet
 +
        # If you have an encrypted device with a regular passphrase,
 +
        # you can add the following line
 +
        params += enc_root=/dev/sda3 enc_type=pass
 +
}
 +
</console>
 +
 
 +
After editing /etc/boot.conf, you just need to run boot-update to update grub.cfg
 +
<console># ##i##boot-update</console>
 +
 
 +
=== /boot on ZFS ===
 +
TBC - pending update to boot-update to support this
 +
 
 +
== Final configuration ==
 +
=== Add the zfs tools to openrc ===
 +
<console># ##i##rc-update add zfs boot</console>
 +
 
 +
=== 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.
 +
 
 +
<console>
 +
Delete the stage3 tarball that you downloaded earlier so it doesn't take up space.
 +
# ##i##cd /
 +
# ##i##rm stage3-latest.tar.xz
 +
 
 +
Set 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##exit
 +
 
 +
Unmount all the kernel filesystem stuff and boot (if you have a separate /boot)
 +
# ##i##umount -l proc dev sys boot
 +
 
 +
Turn off the swap
 +
# ##i##swapoff /dev/zvol/tank/swap
 +
 
 +
Export the zpool
 +
# ##i##cd /
 +
# ##i##zpool export tank
 +
 
 +
Reboot
 +
# ##i##reboot
 +
</console>
 +
 
 +
{{fancyimportant|'''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.
 +
 
 +
== After reboot ==
 +
=== Create initial ZFS Snapshot ===
 +
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 system, type the following:
 +
<console># ##i##zfs snapshot -r tank@install</console>
  
* --kernel-config: use the given configfile. If you only give a filename here, it is searched for in your current working dir. You can also use a relative or an absolute path leading to your configfile here (for example: "--kernel-config=/usr/src/linux/configfile").
+
To see if your snapshot was taken, type:
* all: rebuild the kernel image and the initramfs ramdisk image (aside of kernel modules, the ramdisk image contains tools such as BusyBox and some generic startup scripts, depending on options you use on the command line several additional tools like lvm or raid volume management can be incorporated as well).
+
<console># ##i##zfs list -t snapshot</console>
  
{{ fancyimportant|Unless explicitly stated via ''--no-clean'' or ''--no-mrproper'', Genkernel will do a '''make mrproper''' in the kernel source tree, thus cleaning a previous build '''and removing the previous kernel configuration file''' in it.
+
If your machine ever fails and you need to get back to this state, just type (This will only revert your / dataset while keeping the rest of your data intact):
}}
+
<console># ##i##zfs rollback tank/os/funtoo/root@install</console>
  
If you use Genkernel to rebuild a Linux kernel on SPARC64, remember to either:
+
{{fancyimportant|'''For a detailed overview, presentation of ZFS' capabilities, as well as usage examples, please refer to the [[ZFS_Fun|ZFS Fun]] page.'''}}
* Set '''sparc64-unknown-linux-gnu-''' in ''General setup --> Cross-compiler tool prefix''
+
* Put '''--kernel-cross-compile=sparc64-unknown-linux-gnu-''' on the Genkernel command line
+
  
Once the kernel has been compiled and the ram disk has been generated, the kernel image plus its companion files (initramfs image and System.map) are placed in the /boot directory. You can use your favourite tool to update your bootloader configuration files.
+
[[Category:HOWTO]]
 +
[[Category:Filesystems]]
 +
[[Category:Featured]]
  
[[Category:Internals]]
+
__NOTITLE__
[[Category:Funtoo features]]
+
[[Category:Kernel]]
+

Revision as of 21:55, 28 January 2014

Introduction

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.

Introduction to ZFS

Since ZFS is a new technology for Linux, it can be helpful to understand some of its benefits, particularly in comparison to BTRFS, another popular next-generation Linux filesystem:

  • On Linux, the ZFS code can be updated independently of the kernel to obtain the latest fixes. btrfs is exclusive to Linux and you need to build the latest kernel sources to get the latest fixes.
  • ZFS is supported on multiple platforms. The platforms with the best support are Solaris, FreeBSD and Linux. Other platforms with varying degrees of support are NetBSD, Mac OS X and Windows. btrfs is exclusive to Linux.
  • ZFS has the Adaptive Replacement Cache replacement algorithm while btrfs uses the Linux kernel's Last Recently Used replacement algorithm. The former often has an overwhelmingly superior hit rate, which means fewer disk accesses.
  • ZFS has the ZFS Intent Log and SLOG devices, which accelerates small synchronous write performance.
  • ZFS handles internal fragmentation gracefully, such that you can fill it until 100%. Internal fragmentation in btrfs can make btrfs think it is full at 10%. Btrfs has no automatic rebalancing code, so it requires a manual rebalance to correct it.
  • ZFS has raidz, which is like RAID 5/6 (or a hypothetical RAID 7 that supports 3 parity disks), except it does not suffer from the RAID write hole issue thanks to its use of CoW and a variable stripe size. btrfs gained integrated RAID 5/6 functionality in Linux 3.9. However, its implementation uses a stripe cache that can only partially mitigate the effect of the RAID write hole.
  • ZFS send/receive implementation supports incremental update when doing backups. btrfs' send/receive implementation requires sending the entire snapshot.
  • ZFS supports data deduplication, which is a memory hog and only works well for specialized workloads. btrfs has no equivalent.
  • ZFS datasets have a hierarchical namespace while btrfs subvolumes have a flat namespace.
  • ZFS has the ability to create virtual block devices called zvols in its namespace. btrfs has no equivalent and must rely on the loop device for this functionality, which is cumbersome.

The only area where btrfs is ahead of ZFS is in the area of small file efficiency. btrfs supports a feature called block suballocation, which enables it to store small files far more efficiently than ZFS. It is possible to use another filesystem (e.g. reiserfs) on top of a ZFS zvol to obtain similar benefits (with arguably better data integrity) when dealing with many small files (e.g. the portage tree).

Disclaimers

Warning: This guide is a work in progress. Expect some quirks.
Important: 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!

Video Tutorial

As a companion to the install instructions below, a YouTube video ZFS install tutorial is now available:

Downloading the ISO (With ZFS)

In order for us to install Funtoo on ZFS, you will need an environment that provides the ZFS tools. Therefore we will download a customized version of System Rescue CD with ZFS already included. When booting, use the "alternate"-kernel. The ZFS-module won't work with the default kernel.

Name: sysresccd-4.0.0_zfs_0.6.2.iso   (522 MB)
Release Date: 2014-01-18
md5sum 5a6530088e63b516765f78076a2e4859


Download System Rescue CD with ZFS

Creating a bootable USB from ISO

After you download the iso, you can do the following steps to create a bootable USB:

Make a temporary directory
# mkdir /tmp/loop

Mount the iso
# mount -o ro,loop /root/sysresccd-4.0.0_zfs_0.6.2.iso /tmp/loop

Run the usb installer
# /tmp/loop/usb_inst.sh

That should be all you need to do to get your flash drive working.

When you are booting into system rescue cd, make sure you select the alternative 64 bit kernel. ZFS support was specifically added to the alternative 64 bit kernel rather than the standard 64 bit kernel.

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.

We will be showing you how to partition it manually because if you partition it manually you get to create your own layout, you get to have your own separate /boot partition (Which is nice since not every bootloader supports booting from ZFS pools), and you get to boot into RAID10, RAID5 (RAIDZ) pools and any other layouts due to you having a separate /boot partition.

gdisk (GPT Style)

A Fresh Start:

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 ↵
Warning: 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 layout.

Create Partition 1 (boot):

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

Create Partition 2 (BIOS Boot Partition):

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

Create Partition 3 (ZFS):

Command: n ↵
Partition Number: 
First sector: 
Last sector: 
Hex Code: bf00 ↵

Command: p ↵

Number  Start (sector)    End (sector)  Size       Code  Name
   1            2048          514047   250.0 MiB   8300  Linux filesystem
   2          514048          579583   32.0 MiB    EF02  BIOS boot partition
   3          579584      1953525134   931.2 GiB   BF00  Solaris root

Command: w ↵


Format your boot volume

Format your separate /boot partition:

# mkfs.ext2 /dev/sda1

Encryption (Optional)

If you want encryption, then create your encrypted vault(s) now by doing the following:

# cryptsetup luksFormat /dev/sda3
# cryptsetup luksOpen /dev/sda3 vault_1

Create the zpool

We will first create the pool. The pool will be named `tank` 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 tank /dev/sda3
Important: If you are using encrypted root, change /dev/sda3 to /dev/mapper/vault_1.
Note: ashift=12 should be use if you have a newer, advanced format disk that has a sector size of 4096 bytes. If you have an older disk with 512 byte sectors, you should use ashift=9 or don't add the option for auto detection.
Note: If you have a previous pool that you would like to import, you can do a: zpool import -f -R /mnt/funtoo <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 -p tank/os/funtoo
# zfs create -o mountpoint=/ tank/os/funtoo/root

Optional, but recommended datasets: /home
# zfs create -o mountpoint=/home tank/os/funtoo/home

Optional datasets: /usr/src, /usr/portage/{distfiles,packages}
# zfs create -o mountpoint=/usr/src tank/os/funtoo/src
# zfs create -o mountpoint=/usr/portage -o compression=off tank/os/funtoo/portage
# zfs create -o mountpoint=/usr/portage/distfiles tank/os/funtoo/portage/distfiles
# zfs create -o mountpoint=/usr/portage/packages tank/os/funtoo/portage/packages

Create your swap zvol

Make your swap +1G greater than your RAM. An 8G machine would have 9G of SWAP (This is kinda big though). For machines with this much memory, You could just make it 2G if you don't have any problems.

# zfs create -o sync=always -o primarycache=metadata -o secondarycache=none -o volblocksize=4K -V 1G tank/swap

Format your swap zvol

# mkswap -f /dev/zvol/tank/swap
# swapon /dev/zvol/tank/swap

Now we will continue to install funtoo.

Installing Funtoo

Download and extract the Funtoo stage3 and continue installation as normal.

Then once you've extracted the stage3, chroot into your new funtoo environment:

Go into the directory that you will chroot into
# cd /mnt/funtoo

Mount your boot drive
# mount /dev/sda1 /mnt/funtoo/boot

Bind the kernel related directories
# mount -t proc none /mnt/funtoo/proc
# mount --rbind /dev /mnt/funtoo/dev
# mount --rbind /sys /mnt/funtoo/sys

Copy network settings
# cp /etc/resolv.conf /mnt/funtoo/etc/

chroot into your new funtoo environment
# env -i HOME=/root TERM=$TERM chroot /mnt/funtoo /bin/bash --login

Place your mountpoints into your /etc/mtab file
# cat /proc/mounts > /etc/mtab

Sync your tree
# emerge --sync

Add filesystems to /etc/fstab

Before we continue to compile and or install our kernel in the next step, we will edit the /etc/fstab file because if we decide to install our kernel through portage, portage will need to know where is your /boot so that it can place the files in there. We also need to update /etc/mtab so our system knows what is mounted

{{{name}}}
{{{body}}}

Kernel Configuration

To speed up this step, you can install "bliss-kernel" since it's already properly configured for ZFS and a lot of other configurations. The kernel is also compiled and ready to go. To install sys-kernel/bliss-kernel type the following:

# emerge -av bliss-kernel

Now make sure that your /usr/src/linux symlink is pointing to this kernel by typing the following:

# eselect kernel list
Available kernel symlink targets:
[1]   linux-3.10.10-FB.01 *

You should see a star next to the bliss-kernel version you installed. In this case it was 3.10.10-FB.01. If it's not set, you can type eselect kernel set #.

Installing the ZFS userspace tools and kernel modules

Emerge sys-fs/zfs, sys-kernel/spl, and sys-fs/zfs-kmod:

# emerge -av zfs spl zfs-kmod

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

Note: SPL stands for: Solaris Porting Layer
# zpool status
# zfs list

If everything worked, continue.

Install the bootloader

GRUB 2

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 environment

Once all this is checked, 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:

# emerge -av grub

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

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

Now try to install sys-boot/grub:

# grub-install --recheck /dev/sda

You should receive the following message:

Installation finished. No error reported.

If not, then go back to the above checklist.

LILO

Before you do this, make sure the following checklist is followed:

  • /dev, /proc and /sys are mounted.
  • Installed the sys-fs/zfs package from the tree.

Once the above requirements are met, LILO can be installed.

Now we will install sys-boot/lilo.

# emerge -av sys-boot/lilo

Once the installation of LILO is complete we will need to edit the lilo.conf file.

{{{name}}}
{{{body}}}

All that is left now is to install the bootcode to the MBR.

This can be accomplished by running:

# /sbin/lilo

If it is successful you should see:

Warning: LBA32 addressing assumed
Added Funtoo + *
One warning was issued

Create the initramfs

There are two ways to do this, you can use genkernel, or you can use my bliss initramfs creator. I will show you both.

genkernel

# emerge -av sys-kernel/genkernel
# You only need to add --luks if you used encryption
# genkernel --zfs --luks initramfs

Bliss Initramfs Creator

If you are encrypting your drives, then add the "luks" use flag to your package.use before emerging:

# echo "sys-kernel/bliss-initramfs luks" >> /etc/portage/package.use

Now install the creator:

# emerge bliss-initramfs


Then go into the install directory, run the script as root, and place it into /boot:

# cd /opt/bliss-initramfs
# ./createInit
# mv initrd-<kernel_name> /boot

<kernel_name> is the name of what you selected in the initramfs creator, and the name of the outputted file.

Using boot-update

/boot on separate partition

If you created a separate non-zfs partition for boot then configuring boot-update is almost exactly the same as a normal install except that auto detection for root does not work. You must tell boot-update what your root is.

Genkernel

If your using genkernel you must add 'real_root=ZFS=<root>' and 'dozfs' to your params. Example entry for boot.conf:

"Funtoo ZFS" {
        kernel vmlinuz[-v]
        initrd initramfs-genkernel-x86_64[-v]
        params real_root=ZFS=tank/os/funtoo/root
        params += dozfs=force
        # Also add 'params += crypt_root=/dev/sda3' if you used encryption
        # Adjust the above setting to your system if needed
}

Bliss Initramfs Creator

If you used the Bliss Initramfs Creator then all you need to do is add 'root=<root>' to your params. Example entry for boot.conf:

"Funtoo ZFS" {
        kernel vmlinuz[-v]
        initrd initrd[-v]
        params root=tank/os/funtoo/root quiet
        # If you have an encrypted device with a regular passphrase,
        # you can add the following line
        params += enc_root=/dev/sda3 enc_type=pass
}

After editing /etc/boot.conf, you just need to run boot-update to update grub.cfg

# boot-update

/boot on ZFS

TBC - pending update to boot-update to support this

Final configuration

Add the zfs tools to openrc

# rc-update add zfs boot

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 tarball that you downloaded earlier so it doesn't take up space.
# cd /
# rm stage3-latest.tar.xz

Set your root password
# 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
# exit

Unmount all the kernel filesystem stuff and boot (if you have a separate /boot)
# umount -l proc dev sys boot

Turn off the swap
# swapoff /dev/zvol/tank/swap

Export the zpool
# cd /
# zpool export tank

Reboot
# reboot
Important: 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.

After reboot

Create initial ZFS Snapshot

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 system, type the following:

# zfs snapshot -r tank@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 (This will only revert your / dataset while keeping the rest of your data intact):

# zfs rollback tank/os/funtoo/root@install
Important: For a detailed overview, presentation of ZFS' capabilities, as well as usage examples, please refer to the ZFS Fun page.