Difference between revisions of "Rootfs over encrypted lvm"

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This howto describes how to setup LVM and rootfs with cryptoLUKS-encrypted drive  
This howto describes how to setup LVM and rootfs with cryptoLUKS-encrypted drive. It is not meant to be a standalone installation guide, rather, it is meant to be read alongside the [[Funtoo Linux Installation]] Guide.


= Prepare the hard drive and partitions =
== Prepare the hard drive and partitions ==
This is an example partition scheme, you may want to choose differently.
This is an example partition scheme, you may want to choose differently.
<code>/dev/sda1</code> used as <code>/boot</code>. <code>/dev/sda2</code> will be encrypted drive with LVM.
<code>/dev/sda1</code> used as <code>/boot</code>. <code>/dev/sda2</code> will be encrypted drive with LVM.
 
* <code>/dev/sda1</code> -- <code>/boot</code> partition.
* <code>/dev/sda1</code> -- <code>/boot</code> partition.  
* <code>/dev/sda2</code> -- BIOS boot partition (not needed for MBR - only needed if you are using GPT) This step required for GRUB2. For more info, see: [http://www.funtoo.org/Funtoo_Linux_Installation#Prepare_Hard_Disk] for more information on GPT and MBR.  
* <code>/dev/sda2</code> -- BIOS boot partition (not needed for MBR - only needed if you are using GPT) This step required for GRUB2. For more info, see: [http://www.funtoo.org/Funtoo_Linux_Installation#Prepare_Hard_Disk] for more information on GPT and MBR.  
* <code>/dev/sda3</code> -- <code>/</code> partition, will be the drive with LUKS and LVM.
* <code>/dev/sda3</code> -- <code>/</code> partition, will be the drive with LUKS and LVM.


With UEFI:
* <code>/dev/sda1</code> -- <tt>/boot</tt>
* <code>/dev/sda2</code> -- <tt>/</tt> partition
=== Wipe the hard drive ===
<console>
<console>
# ##i##dd if=/dev/zero of=/dev/sda3 bs=100M
# ##i##gdisk /dev/sda
# ##i##dd if=/dev/urandom of=/dev/sda3 bs=100M
 
Command: ##i##x ↵
Expert command: ##i##z ↵
About to wipe out GPT on /dev/sda. Proceed?: ##i##y ↵
GPT data structures destroyed! You may now partition the disk using fdisk or other utilities.
Blank out MBR?: ##i##y ↵
</console>
{{Fancywarning|This action will destroy all data on the disk.}}
 
== Encrypting the drive ==
Read more about different cipher options here: [http://blog.wpkg.org/2009/04/23/cipher-benchmark-for-dm-crypt-luks/]
<console>
# ##i##cryptsetup --cipher aes-xts-plain64 luksFormat /dev/sda3
</console>
</console>
The <code>dd</code> part is optional, and the command only needs to be run for security reasons (i.e only if you had top secret files on your drive). The command overwrites the lingering data on the device with random data. It takes around 6 hours to complete for a 200GB drive.


{{Note}} You will get a message about reaching the end of the device when the <code>dd</code> command has finished. This behavior is intended.
Or use SHA512 for increase security. Do NOT use SHA-1: LUKS disk encryption. As the cryptography expert Bruce Schneier already told in year 2005, do not use SHA-1 because its broken. See his article here: [http://www.schneier.com/blog/archives/2005/02/sha1_broken.html]
 
<console>
# ##i##cryptsetup --cipher twofish-xts-plain64 --hash sha512 --key-size 256 luksFormat /dev/sda3
</console>


= Encrypting the drive =
== Initializes the volume ==
Initializes the volume, and sets an initial key or passphrase:
<console>
<console>
# ##i##cryptsetup --cipher aes-xts-plain64 luksFormat /dev/sda3
# ##i##cryptsetup luksOpen /dev/sda3 dmcrypt_root
# ##i##cryptsetup luksOpen /dev/sda3 dmcrypt_root
</console>
</console>


There you'll be prompted to enter your password phrase for encrypted drive, type your paranoid password there.
There you'll be prompted to enter your password phrase for encrypted drive, type your paranoid password there.
 
{{Fancywarning|The default keymap at boot time is '''us'''. If you enter your passphrase using a different keymap, you won't be able to unlock your crypt volume if the passphrase contains any characters that are located elsewere on your keyboard layout that with the us layout.}}
= Create logical volumes =
= Create logical volumes =
<console>
<console>
Line 35: Line 54:
</console>
</console>
Feel free to specify your desired size by altering the numbers after the -L flag. For example, to make your portage dataset 20GB's, use the flag -L20G instead of -L5G.
Feel free to specify your desired size by altering the numbers after the -L flag. For example, to make your portage dataset 20GB's, use the flag -L20G instead of -L5G.
{{fancynote| Please, notice that above mentioned partitioning scheme is an example and not a default recommendation, change it accordingly to desired scheme.}}


= Create a filesystem on volumes =
= Create a filesystem on volumes =
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* '''lvm2'''
* '''lvm2'''
* '''a bootloader (grub recommended)'''
* '''a bootloader (grub recommended)'''
* '''kernel sources (gentoo-sources recommended)'''
* '''kernel sources '''


= Editing the fstab =
= Editing the fstab =
Fire up your favorite text editor to edit <code>/etc/fstab</code>. You want to put the following in the file:
Fire up your favorite text editor to edit <code>/etc/fstab</code>. You want to put the following in the file:
<pre>
 
{{file|name=/etc/fstab|desc= |body=
# <fs>                  <mountpoint>  <type>    <opts>                          <dump/pass>
# <fs>                  <mountpoint>  <type>    <opts>                          <dump/pass>
/dev/sda1              /boot        ext2      noauto,noatime                  1 2
/dev/sda1              /boot        ext2      noauto,noatime                  1 2
Line 73: Line 94:
/dev/mapper/vg-portage  /usr/portage  ext4      noatime,nodiratime              0 0
/dev/mapper/vg-portage  /usr/portage  ext4      noatime,nodiratime              0 0
/dev/mapper/vg-home    /home        ext4      noatime,nodiratime              0 0
/dev/mapper/vg-home    /home        ext4      noatime,nodiratime              0 0
</pre>
}}


= Kernel options =
== Kernel options ==
{{Note}}This part is particularly important: pay close attention.
{{fancynote| This part is particularly important: pay close attention. }}<br>
{{kernelop
{{kernelop
|'''General setup --->'''
|title=
|'''[*] Initial RAM filesystem and RAM disk (initramfs/initrd) support'''
|desc=
General setup --->
      [*] Initial RAM filesystem and RAM disk (initramfs/initrd) support
}}
}}
{{kernelop
{{kernelop
|'''Device Drivers --->''' <br> '''Generic Driver Options --->'''
|title=
|'''[*] Maintain a devtmpfs filesystem to mount at /dev''' <br>
|desc=
Device Drivers --->
      Generic Driver Options --->  
      [*] Maintain a devtmpfs filesystem to mount at /dev
}}
}}
{{kernelop
{{kernelop
|'''Device Drivers --->''' <br> '''[*] Multiple devices driver support --->'''
|title=
|'''<*>Device Mapper Support''' <br> '''<*> Crypt target support'''
|desc=
Device Drivers --->
      [*] Multiple devices driver support --->
      <*>Device Mapper Support
        <*> Crypt target support
}}
}}
{{kernelop
{{kernelop
|'''Cryptographic API --->'''
|title=
|'''-*-AES cipher algorithms''' <br> '''<*> XTS support'''
|desc=
Cryptographic API --->
      <*> XTS support
      -*-AES cipher algorithms
}}
}}


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'''Build your initramfs with [https://bitbucket.org/piotrkarbowski/better-initramfs better-initramfs] project.'''
'''Build your initramfs with [https://bitbucket.org/piotrkarbowski/better-initramfs better-initramfs] project.'''


{{note}}better-initramfs supports neither dynamic modules nor udev, so you should compile your kernel with built-in support for your block devices.
{{fancynote| better-initramfs supports neither dynamic modules nor udev, so you should compile your kernel with built-in support for your block devices and file system support.}}


<console>
<console>
Line 131: Line 161:
# ##i##less ChangeLog
# ##i##less ChangeLog
</console>
</console>
{{Note}}Please read the ChangeLog carefuly and perform necessary updates to <code>/etc/boot.conf</code>. Also, please backup the working <code>/boot/initramfs.cpio.gz</code> and <code>/etc/boot.conf</code> before updating better-initramfs.
{{fancynote| Please read the ChangeLog carefuly and perform necessary updates to <code>/etc/boot.conf</code>. Also, please backup the working <code>/boot/initramfs.cpio.gz</code> and <code>/etc/boot.conf</code> before updating better-initramfs.}}
Alternatively and much faster is to install better-initramfs-bin package, recently added to Funtoo's portage tree:
<console>
# ##i##emerge better-initramfs-bin
</console>


== Genkernel ==
== Genkernel ==
Line 137: Line 171:
<console>
<console>
# ##i##genkernel --kernel-config=/path/to/your/custom-kernel-config --no-mrproper --makeopts=-j5 --install --lvm --luks all </console>
# ##i##genkernel --kernel-config=/path/to/your/custom-kernel-config --no-mrproper --makeopts=-j5 --install --lvm --luks all </console>
Configure the bootloader as described above, with correct kernel and initramfs images names. An example for genkernel and grub2:


{{code|/etc/boot.conf|<pre>
== Bootloader Configuration ==
=== Grub2 configuration ===
Emerge Grub2 with device-mapper support
<console>
# ##i##echo 'sys-boot/grub device-mapper' >> /etc/portage/package.use/grub
# ##i##emerge grub
</console>
 
==== better-initramfs ====
An example <code>/etc/boot.conf</code> for better-initramfs:
 
<pre>
boot {
boot {
   generate grub
   generate grub
Line 146: Line 190:
}
}
"Funtoo Linux" {
"Funtoo Linux" {
   kernel kernel-genkernel-x86_64-2.6.39
   kernel vmlinuz[-v]
   initrd initramfs-genkernel-x86_64-2.6.39
   initrd /initramfs.cpio.gz
   params += crypt_root=/dev/sda3 dolvm real_root=/dev/mapper/vg-root  rootfstype=ext4 resume=swap:/dev/mapper/vg-swap quiet
   params += enc_root=/dev/sda3 lvm luks root=/dev/mapper/vg-root  rootfstype=ext4 resume=swap:/dev/mapper/vg-swap quiet
}</pre>}}
}
</pre>
 
Now, run <code>boot-update</code> to write the configuration files to <code>/boot/grub/grub.cfg</code>
 
==== genkernel ====
Configure the bootloader as described above, with correct kernel and initramfs images names. An example for genkernel and grub2. You will be editing <code>/etc/boot.conf</code>:


<pre>
= Bootloader Configuration =
== Grub2 configuration ==
An example of <code>/etc/boot.conf</code> for better-initramfs
{{code|/etc/boot.conf|<pre>
boot {
boot {
   generate grub
   generate grub
Line 162: Line 208:
}
}
"Funtoo Linux" {
"Funtoo Linux" {
   kernel bzImage[-v]
   kernel kernel-genkernel-x86_64-3.13.0
   initrd /initramfs.cpio.gz
   initrd initramfs-genkernel-x86_64-3.13.0
   params += enc_root=/dev/sda3 lvm luks root=/dev/mapper/vg-root  rootfstype=ext4 resume=swap:/dev/mapper/vg-swap quiet
   params += crypt_root=/dev/sda3 dolvm real_root=/dev/mapper/vg-root  rootfstype=ext4 resume=swap:/dev/mapper/vg-swap quiet
}</pre>}}
}
 
</pre>
Now, run <code>boot-update</code> to write the configuration files to <code>/boot/grub/grub.cfg</code>


== Lilo configuration ==
=== Lilo configuration ===
For oldschool geeks, an example for lilo bootloader. Emerge lilo with device-mapper support
For oldschool geeks, an example for lilo bootloader. Emerge lilo with device-mapper support
<console>
<console>
Line 176: Line 221:
</console>
</console>


{{code|/etc/lilo.conf|<pre>append="init=/linuxrc dolvm crypt_root=/dev/sda2 real_root=/dev/mapper/vg-root"
Example <code>/etc/lilo.conf</code> for genkernel:
 
<pre>
append="init=/linuxrc dolvm crypt_root=/dev/sda2 real_root=/dev/mapper/vg-root"
boot=/dev/sda
boot=/dev/sda
compact
compact
Line 184: Line 232:
read-only
read-only
timeout=50
timeout=50
image=/boot/kernel-genkernel-x86_64-2.6.39
image=/boot/kernel-genkernel-x86_64-3.13.0
initrd=/boot/initramfs-genkernel-x86_64-2.6.39
initrd=/boot/initramfs-genkernel-x86_64-3.13.0
label=funtoo
label=funtoo
</pre>}}
</pre>


== Syslinux bootloader setup ==
=== Syslinux bootloader setup ===
Syslinux is another advanced bootloader which you can find on all live CD's. Syslinux bootloader does not require additional BIOS boot partition. /dev/sda2 is the root partition.
Syslinux is another advanced bootloader which you can find on all live CD's. Syslinux bootloader does not require additional BIOS boot partition. /dev/sda2 is the root partition.
<console>
# ##i##emerge syslinux
# ##i##mkdir /boot/extlinux
# ##i##extlinux --install /boot/extlinux
# ##i##dd bs=440 conv=notrunc count=1 if=/usr/share/syslinux/mbr.bin of=/dev/sda
- or -
# ##i##sgdisk /dev/sda --attributes=1:set:2
# ##i##dd bs=440 conv=notrunc count=1 if=/usr/share/syslinux/gptmbr.bin of=/dev/sda, for GPT partition
</console>
Example <code>/boot/extlinux/extlinux.conf</code> for better-initramfs:
<pre>
<pre>
# emerge syslinux
LABEL kernel1_bzImage-3.2.1
# mkdir /boot/extlinux
# extlinux --install /boot/extlinux
# dd bs=440 conv=notrunc count=1 if=/usr/share/syslinux/mbr.bin of=/dev/sda
- or -
# sgdisk /dev/sda --attributes=1:set:2
# dd bs=440 conv=notrunc count=1 if=/usr/share/syslinux/gptmbr.bin of=/dev/sda, for GPT partition</pre>
{{code|/boot/extlinux/extlinux.conf|<pre>LABEL kernel1_bzImage-3.2.1
MENU LABEL Funtoo Linux bzImage-3.2.1
MENU LABEL Funtoo Linux bzImage-3.2.1
LINUX /bzImage-3.2.1
LINUX /bzImage-3.2.1
INITRD /initramfs.cpio.gz
INITRD /initramfs.cpio.gz
APPEND rootfstype=ext4 luks enc_root=/dev/sda2 lvm root=/dev/mapper/vg-root
APPEND rootfstype=ext4 luks enc_root=/dev/sda2 lvm root=/dev/mapper/vg-root
</pre>}}
</pre>


= Final steps =
== Final steps ==
Umount everything, close encrypted drive and reboot
Umount everything, close encrypted drive and reboot
<console>
<console>
Line 214: Line 267:
</console>
</console>
After reboot you will get the following:
After reboot you will get the following:
<pre>>>> better-initramfs started. Kernel version 2.6.35-gentoo-r10
<console>
>>> better-initramfs started. Kernel version 2.6.35-gentoo-r10
>>> Create all the symlinks to /bin/busybox.
>>> Create all the symlinks to /bin/busybox.
>>> Initiating /dev/dir
>>> Initiating /dev/dir
Line 222: Line 276:
No volume group found
No volume group found
>>> Opening encrypted partition and mapping to /dev/mapper/dmcrypt_root
>>> Opening encrypted partition and mapping to /dev/mapper/dmcrypt_root
Enter passphrase fore /dev/sda2:</pre>
Enter passphrase fore /dev/sda2:
</console>
Type your password
Type your password


<pre>>>> Again, getting LVM volumes up (if any, after map dmcrypt).
<console>
>>> Again, getting LVM volumes up (if any, after map dmcrypt).
   Reading all physical volumes.  This may take a while...
   Reading all physical volumes.  This may take a while...
   Found volume group "vg" using metadata type lvm2
   Found volume group "vg" using metadata type lvm2
Line 240: Line 296:
Password:
Password:
Last login: Thu Oct 14 20:49:21 EEST 2010 on tty1
Last login: Thu Oct 14 20:49:21 EEST 2010 on tty1
oleg@orion ~ %</pre>
oleg@orion ~ %
</console>


= Additional links =
== Additional links and information ==
* [[gentoo-wiki:Root filesystem over LVM2, DM-Crypt and RAID|Root filesystem over LVM2, DM-Crypt, and RAID]]
* [[gentoo-wiki:Root filesystem over LVM2, DM-Crypt and RAID|Root filesystem over LVM2, DM-Crypt, and RAID]]
* [http://wiki.archlinux.org/index.php/System_Encryption_with_LUKS_for_dm-crypt System Encryption with LUKS for dm-crypt]
* [http://wiki.archlinux.org/index.php/System_Encryption_with_LUKS_for_dm-crypt System Encryption with LUKS for dm-crypt]

Revision as of 17:34, May 10, 2015

This howto describes how to setup LVM and rootfs with cryptoLUKS-encrypted drive. It is not meant to be a standalone installation guide, rather, it is meant to be read alongside the Funtoo Linux Installation Guide.

Prepare the hard drive and partitions

This is an example partition scheme, you may want to choose differently. /dev/sda1 used as /boot. /dev/sda2 will be encrypted drive with LVM.

  • /dev/sda1 -- /boot partition.
  • /dev/sda2 -- BIOS boot partition (not needed for MBR - only needed if you are using GPT) This step required for GRUB2. For more info, see: [1] for more information on GPT and MBR.
  • /dev/sda3 -- / partition, will be the drive with LUKS and LVM.

With UEFI:

  • /dev/sda1 -- /boot
  • /dev/sda2 -- / partition

Wipe the hard drive

root # 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 action will destroy all data on the disk.

Encrypting the drive

Read more about different cipher options here: [2]

root # cryptsetup --cipher aes-xts-plain64 luksFormat /dev/sda3

Or use SHA512 for increase security. Do NOT use SHA-1: LUKS disk encryption. As the cryptography expert Bruce Schneier already told in year 2005, do not use SHA-1 because its broken. See his article here: [3]

root # cryptsetup --cipher twofish-xts-plain64 --hash sha512 --key-size 256 luksFormat /dev/sda3

Initializes the volume

Initializes the volume, and sets an initial key or passphrase:

root # cryptsetup luksOpen /dev/sda3 dmcrypt_root

There you'll be prompted to enter your password phrase for encrypted drive, type your paranoid password there.

   Warning

The default keymap at boot time is us. If you enter your passphrase using a different keymap, you won't be able to unlock your crypt volume if the passphrase contains any characters that are located elsewere on your keyboard layout that with the us layout.

Create logical volumes

root # pvcreate /dev/mapper/dmcrypt_root
root # vgcreate vg /dev/mapper/dmcrypt_root
root # lvcreate -L10G --name root vg           
root # lvcreate -L2G --name swap vg
root # lvcreate -L5G --name portage vg
root # lvcreate -l 100%FREE -nhome vg

Feel free to specify your desired size by altering the numbers after the -L flag. For example, to make your portage dataset 20GB's, use the flag -L20G instead of -L5G.

   Note
Please, notice that above mentioned partitioning scheme is an example and not a default recommendation, change it accordingly to desired scheme.

Create a filesystem on volumes

root # mkfs.ext2 /dev/sda1
root # mkswap /dev/mapper/vg-swap
root # mkfs.ext4 /dev/mapper/vg-root
root # mkfs.ext4 /dev/mapper/vg-portage
root # mkfs.ext4 /dev/mapper/vg-home

Basic system setup

root # swapon /dev/mapper/vg-swap
root # mkdir /mnt/funtoo
root # mount /dev/mapper/vg-root /mnt/funtoo
root # mkdir -p /mnt/funtoo/{boot,usr/portage,home}
root # mount /dev/sda1 /mnt/funtoo/boot
root # mount /dev/mapper/vg-portage /mnt/funtoo/usr/portage
root # mount /dev/mapper/vg-home /mnt/funtoo/home

Now perform all the steps required for basic system install, please follow [4] don't forget to emerge the following before your install is finished:

  • cryptsetup
  • lvm2
  • a bootloader (grub recommended)
  • kernel sources

Editing the fstab

Fire up your favorite text editor to edit /etc/fstab. You want to put the following in the file:

   /etc/fstab
# <fs>                  <mountpoint>  <type>    <opts>                          <dump/pass>
/dev/sda1               /boot         ext2      noauto,noatime                  1 2
/dev/mapper/vg-swap     none          swap      sw                              0 0
/dev/mapper/vg-root     /             ext4      noatime,nodiratime,defaults     0 1
/dev/sr0                /mnt/cdrom    auto      noauto,ro                       0 0
/dev/mapper/vg-portage  /usr/portage  ext4      noatime,nodiratime              0 0
/dev/mapper/vg-home     /home         ext4      noatime,nodiratime              0 0

Kernel options

   Note
This part is particularly important: pay close attention. 


General setup --->
      [*] Initial RAM filesystem and RAM disk (initramfs/initrd) support
Device Drivers --->
      Generic Driver Options ---> 
      [*] Maintain a devtmpfs filesystem to mount at /dev
Device Drivers --->
      [*] Multiple devices driver support --->
      <*>Device Mapper Support
        <*> Crypt target support
Cryptographic API --->
      <*> XTS support
      -*-AES cipher algorithms

Initramfs setup and configuration

Better-initramfs

Build your initramfs with better-initramfs project.

   Note
better-initramfs supports neither dynamic modules nor udev, so you should compile your kernel with built-in support for your block devices and file system support.
root # cd /opt
root # git clone git://github.com/slashbeast/better-initramfs.git
root # cd better-initramfs
root # less README.rst
root # bootstrap/bootstrap-all
root # make prepare
root # make image

Copy resulting initramfs.cpio.gz to /boot:

root # cp output/initramfs.cpio.gz /boot

Alternatively, a pre-compiled binary initramfs is available at https://bitbucket.org/piotrkarbowski/better-initramfs/downloads

root # wget https://bitbucket.org/piotrkarbowski/better-initramfs/downloads/release-x86_64-v0.7.2.tar.bz2
root # tar xf release-x86_64-v0.5.tar.bz2
root # cd release*
root # gzip initramfs.cpio
root # cp initramfs.cpio.gz /boot

Remember, better-initramfs project is a work in progress, so you need to update from time to time. It can be done easily with git. Go to the better-initramfs source dir and follow:

root # cd /opt/better-initramfs
root # git pull
root # less ChangeLog
   Note
Please read the ChangeLog carefuly and perform necessary updates to /etc/boot.conf. Also, please backup the working /boot/initramfs.cpio.gz and /etc/boot.conf before updating better-initramfs.

Alternatively and much faster is to install better-initramfs-bin package, recently added to Funtoo's portage tree:

root # emerge better-initramfs-bin

Genkernel

Funtoo's genkernel capable to create initramfs for encrypted drive. Compile and install kernel and initramfs of your favorite kernel sources:

root # genkernel --kernel-config=/path/to/your/custom-kernel-config --no-mrproper --makeopts=-j5 --install --lvm --luks all 

Bootloader Configuration

Grub2 configuration

Emerge Grub2 with device-mapper support

root # echo 'sys-boot/grub device-mapper' >> /etc/portage/package.use/grub
root # emerge grub

better-initramfs

An example /etc/boot.conf for better-initramfs:

boot {
  generate grub
  default "Funtoo Linux"
  timeout 3
}
"Funtoo Linux" {
  kernel vmlinuz[-v]
  initrd /initramfs.cpio.gz
  params += enc_root=/dev/sda3 lvm luks root=/dev/mapper/vg-root  rootfstype=ext4 resume=swap:/dev/mapper/vg-swap quiet
}

Now, run boot-update to write the configuration files to /boot/grub/grub.cfg

genkernel

Configure the bootloader as described above, with correct kernel and initramfs images names. An example for genkernel and grub2. You will be editing /etc/boot.conf:

boot {
  generate grub
  default "Funtoo Linux"
  timeout 3
}
"Funtoo Linux" {
  kernel kernel-genkernel-x86_64-3.13.0
  initrd initramfs-genkernel-x86_64-3.13.0
  params += crypt_root=/dev/sda3 dolvm real_root=/dev/mapper/vg-root  rootfstype=ext4 resume=swap:/dev/mapper/vg-swap quiet
}

Lilo configuration

For oldschool geeks, an example for lilo bootloader. Emerge lilo with device-mapper support

root # echo 'sys-boot/lilo device-mapper' >> /etc/portage/package.use/lilo
root # emerge lilo

Example /etc/lilo.conf for genkernel:

append="init=/linuxrc dolvm crypt_root=/dev/sda2 real_root=/dev/mapper/vg-root"
boot=/dev/sda
compact
default=funtoo
lba32
prompt
read-only
timeout=50
image=/boot/kernel-genkernel-x86_64-3.13.0
initrd=/boot/initramfs-genkernel-x86_64-3.13.0
label=funtoo

Syslinux bootloader setup

Syslinux is another advanced bootloader which you can find on all live CD's. Syslinux bootloader does not require additional BIOS boot partition. /dev/sda2 is the root partition.

root # emerge syslinux
root # mkdir /boot/extlinux
root # extlinux --install /boot/extlinux
root # dd bs=440 conv=notrunc count=1 if=/usr/share/syslinux/mbr.bin of=/dev/sda
- or -
root # sgdisk /dev/sda --attributes=1:set:2
root # dd bs=440 conv=notrunc count=1 if=/usr/share/syslinux/gptmbr.bin of=/dev/sda, for GPT partition

Example /boot/extlinux/extlinux.conf for better-initramfs:

LABEL kernel1_bzImage-3.2.1
MENU LABEL Funtoo Linux bzImage-3.2.1
LINUX /bzImage-3.2.1
INITRD /initramfs.cpio.gz
APPEND rootfstype=ext4 luks enc_root=/dev/sda2 lvm root=/dev/mapper/vg-root

Final steps

Umount everything, close encrypted drive and reboot

root # umount -l -v /mnt/funtoo/{dev, proc, home, usr/portage, boot} 
root # vgchange -a n
root # cryptsetup luksClose /dev/sda2 dmcrypt_root

After reboot you will get the following:

>>> better-initramfs started. Kernel version 2.6.35-gentoo-r10
>>> Create all the symlinks to /bin/busybox.
>>> Initiating /dev/dir
>>> Getting LVM volumes up (if any)
Reding all physical volumes. This make take awhile...
No volume group found
No volume group found
>>> Opening encrypted partition and mapping to /dev/mapper/dmcrypt_root
Enter passphrase fore /dev/sda2:

Type your password

>>> Again, getting LVM volumes up (if any, after map dmcrypt).
  Reading all physical volumes.  This may take a while...
  Found volume group "vg" using metadata type lvm2
  4 logical volume(s) in volume group "vg" now active
>>> Mounting rootfs to /newroot
>>> Umounting /sys and /proc.
>>> Switching root to /newroot and executing /sbin/init.
INIT: version 2.88 booting
Loading /libexec/rc/console/keymap
  OpenRC 0.6.1 is starting up Funtoo Linux (x86_64)
...boot messages omitted for clarity
   
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Last login: Thu Oct 14 20:49:21 EEST 2010 on tty1
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