RPi: Customized Unattended Installation

This Instructable is about modifying the Raspberry Pi Noobs Installer.

The default Raspberry Pi (Noobs/Raspbian) installation has a lot of pre-installed software. And Raspbian needs a 8 Gbyte SD-card, to install all these packages. But do you really need all this software for your Raspberry Pi project?
There are probably also several background processes which are not useful for your project. And they all take CPU power and memory from your limited resources. You can disable these processes, but uninstalling unneeded software also removes these processes.

We'll start with modifying the original Noobs-files to enable the silent installer. This will allow an unattended installation, without keyboard and monitor. This makes it very easy to install a Raspberry Zero!

Then we'll change the network setting inside the Installer-files. This will give a fixed IP address, and an automatic Wifi connection, right after installation.

Next step is to configure and minimize the installed software. My first goal is to be able to install on a 4 GByte SD-card.

And, after customizing the OS, it's time to create your own installer: Instructables + Raspbian = Instructian.

Finally, it's time to install Raspbian on a 1 Gbyte SD-card!

Download the latest Noobs installer from the RaspberryPi.org website. The current version is 1.8. (I've used the following modifications since version 1.5.)

Create a copy and open the archive-file with 7zip. Keep this file open, until all steps are completed.

Edit the recovery.cmdline-file in the root-folder. And append "silentinstall" to the end of the arguments list. Save the file and close the editor. There will be a message that the recovery.cmdline was modified. Choose "OK" to update the archive.

-------------------------------------
/recovery.cmdline (add silentinstall)
-------------------------------------
runinstaller quiet ramdisk_size=32768 root=/dev/ram0 init=/init vt.cur_default=1 elevator=deadline silentinstall

Now open the "Os" folder. This folder contains the Raspbian operating system. Opening the Raspbian folder shows the following files:

slides_vga (folder)
root.tar.xz
release_notes.txt
Raspbian.png
partition_setup.sh
partitions.json
os.json
boot.tar.xz

The root.tar.xz and the boot.tar.xz files contain compressed disk images. These are extracted to linux partitions during installation.

Both json-files contain information needed by the installer. You can change the default password (raspberry) by editing the os.json-file:

{
  "name": "Raspbian",
  "version": "jessie",
  "release_date": "2016-02-26",
  "kernel": "4.1",
  "description": "A community-created port of Debian jessie for the Raspberry Pi",
  "url": "http://www.raspbian.org/",
  "username": "pi",
  "password": "raspberry",
  "supported_models": ["Pi Model","Pi 2","Pi Zero","Pi 3"]
}

Next step is to configure a fixed IP-address and WIFI.

We need to alter two files inside the root.tar.xz-file. Open (inside 7Zip) the root.tar.xz-file. And open (also inside 7Zip) the root.tar-file. This will take a while to extract to a temporary location. Browse to the /etc/network-folder and modify the interfaces-file. Replace the wlan0 part with those settings needed for your network:

allow-hotplug wlan0
iface wlan0 inet static
address 192.168.1.11
netmask 255.255.255.0
network 192.168.1.0
broadcast 192.168.1.255
gateway 192.168.1.1
    wpa-conf /etc/wpa_supplicant/wpa_supplicant.conf

Save the changes, close the editor and update the archive. Next file to edit is the wpa_supplicant.conf inside the /etc/wpa_supplicant folder. Append your WIFI setting to the end of this file. Close the file and update the archive (again).

network={
ssid="WifiAtHome"
psk="Password"}

Browse Up (icon left to the folder name) until you get the message that the root.tar file was modified. Choose "OK" to update the archive (this will take a while). Next step is to update the root.tar.xz-file (this takes less time than the root.tar file).

Use SDformatter for formating a SD-card. And extract the modified NOOBS-file onto the SD-card. Insert the card into the Raspberry Pi and wait until the operating system is installed (the green led wil stop blinking).

Now we have an Customized Unattended Installer. And now it is time to start experimenting. Just use this, newly created installer, when something goes wrong.

The default Noobs/Raspbian installation has has much preinstalled software. But how do you determine which packages you really need?

I have used two methods to find the minimum required packages:

• Query all installed packages with "apt list". Each package has a "Priority" and a "Section".
• Raspbian is based on Debian. Installing a "minimal" Debian provides a "needed" package list.

Beware, you can't just start removing files from the SD-card. Most files and packages have dependencies with other files or packages. Use APT (Advanced Package Tool) to remove unwanted software. And there are two ways to remove packages with APT:

• Remove: Packages installed are removed (Does NOT include configuration files).
• Purge: Identical to remove except that any configuration files are deleted too.

Priority

The following bash-script returns all installed packages with their priority:

for i in `apt list --installed | sed 's/\/.*$//' | grep -v "Listing..."`
do
  j=`apt-cache show $i | grep "^Priority:"`
  echo $i": "$j
done > priority.txt

This script creates a priority.txt-file with the following content:

acl: Priority: optional
adduser: Priority: important
adwaita-icon-theme: Priority: optional
alacarte: Priority: optional
alsa-base: Priority: optional
...
xz-utils: Priority: required
zenity: Priority: optional
zenity-common: Priority: optional
zlib1g: Priority: required
zlib1g-dev: Priority: optional

There are 1147 installed packages. The Noobs 1.8 Excel file contains a list of all installed packages. I've used this file to select al unwanted packages.

After installation the following partitions are created on the SD-card:

Device         Boot   Start      End  Sectors  Size Id Type
/dev/mmcblk0p1         8192  2261718  2253527  1.1G  e W95 FAT16 (LBA)
/dev/mmcblk0p2      2261719 15523839 13262121  6.3G  5 Extended
/dev/mmcblk0p5      2269184  2334717    65534   32M 83 Linux
/dev/mmcblk0p6      2334720  2463743   129024   63M  c W95 FAT32 (LBA)
/dev/mmcblk0p7      2465792 15523839 13058048  6.2G 83 Linux

Not all partitions are used by Linux. The first partition is the recovery-partition. It is used for booting the Raspberry Pi. And also contains a recovery-copy of the Raspbian operating system. These are the files which are modified in step 1 of this Instructable.
The second partition is an extended partition. This contains the partitions which are used by Linux.

The /etc/fstab-file shows which files are mounted after booting:

proc            /proc           proc    defaults          0       0
/dev/mmcblk0p6  /boot           vfat    defaults          0       2
/dev/mmcblk0p7  /               ext4    defaults,noatime  0       1
# a swapfile is not a swap partition, no line here
#   use  dphys-swapfile swap[on|off]  for that

The mmcblk0p6 and mmcblk0p7 are partitions created by the installer and all files from boot.tar.xz and root.tar.xz are copied to these partitions.

Te root-partition (/) has a size of 6.2 Gbyte. And "df -k" shows that 58% of the file system is in use:

Filesystem     1K-blocks    Used Available Use% Mounted on
/dev/root        6295280 3423868   2528580  58% /
devtmpfs          469708       0    469708   0% /dev
tmpfs             474028       0    474028   0% /dev/shm
tmpfs             474028    6436    467592   2% /run
tmpfs               5120       4      5116   1% /run/lock
tmpfs             474028       0    474028   0% /sys/fs/cgroup
/dev/mmcblk0p6     64366   19948     44418  31% /boot
tmpfs              94808       0     94808   0% /run/user/1000
/dev/mmcblk0p5     30701     397     28011   2% /media/pi/SETTINGS

Notice partition 5 (/dev/mmcblk0p5). This partition doesn't show up in the /etc/fstab-file. It is automatically mounted after booting (just like any other USB-storage).

Summary

A default installation has the following partitions on the SD-card:

• Partition 1: Boot and recovery files (1.1 Gbyte).
• Partition 2: Extended partition which contains partition 5, 6 and 7.
• Partition 5: Configuration files
• Partition 6: Boot-partition
• Partition 7: Root-partition (6.2 Gbyte, 58% in use).

The default Noobs installation will never fit on a 4 Gbyte SD-card. This requires 58% of 6.2Gbyte = 3,6 Gbyte for the Linux files and 1.1 Gbyte for the installer.

After installing NOOBS there are about 110 active processes (ps -ef | wc -l). Some of these processes are required for the graphical interface. Because my projects don't require a graphical interface, it's time to turn this off:

sudo raspi-config

2 - Change User Password 
3 - boot options: No need for graphical interface: B1 Console 
9 - Advanced options: Hostname : chronos 

Reboot your Raspberry Pi, now there are 86 active processes.

Next step is to remove all unnecessary packages.

The first, to delete, packages are the "non-free/devel" packages. They are all optional, and are the largest section (second image).

df -h /
Filesystem      Size  Used Avail Use% Mounted on
/dev/root        6295280 3423868   2528580  58% /

sudo apt purge oracle-java8-jdk wolfram-engine

df -k /
Filesystem     1K-blocks    Used Available Use% Mounted on
/dev/root        6295280 2805012   3147436  48% /

And the used space in the root-partition went from 58% to 48%.

I've also uninstalled all GUI (and other unneeded) packages, using my Excel-file, except libx11-data and x11-common (these files still have dependencies).

sudo apt purge adwaita-icon-theme coinor-libcbc3 coinor-libcgl1 coinor-libclp1 coinor-libcoinutils3 coinor-libosi1 dbus-x11 dc desktop-base epiphany-browser epiphany-browser-data galculator gnome-desktop3-data gnome-icon-theme gnome-icon-theme-symbolic gnome-menus gnome-themes-standard gnome-themes-standard-data gpicview gsettings-desktop-schemas gtk2-engines gtk2-engines-clearlookspix gtk2-engines-pixbuf gvfs-backends gvfs-fuse libgnome-menu-3-0 libreoffice libreoffice-base libreoffice-base-drivers libreoffice-gtk libreoffice-sdbc-hsqldb lightdm lightdm-gtk-greeter lp-solve lxappearance lxappearance-obconf lxde-common lxde-icon-theme lxinput lxmenu-data lxpanel lxpanel-data lxrandr lxsession lxtask lxterminal minecraft-pi nuscratch omxplayer openbox penguinspuzzle pi-package pi-package-data pi-package-session pipanel python-minecraftpi python3-minecraftpi raspberrypi-artwork raspberrypi-ui-mods scratch scrot smartsim va-driver-all vdpau-va-driver x11-utils x11-xkb-utils x11-xserver-utils x2x xarchiver xauth xcompmgr xfonts-utils xinit xkb-data xserver-common xserver-xorg xserver-xorg-core xserver-xorg-input-all xserver-xorg-input-evdev xserver-xorg-input-synaptics xserver-xorg-video-fbdev xserver-xorg-video-fbturbo zenity zenity-common

sudo apt-get autoremove

df -k /
Filesystem     1K-blocks    Used Available Use% Mounted on
/dev/root        6295280 2340092   3612356  40% /

We saved about 1 Gbyte, and the total size of all software is now 2,3 Gbyte. The original installer used 1.1 Gbyte. Giving a total size below 4 Gbyte.

Before continuing clean up some directories in the pi-home folder.

cd /home/pi
rm -rf .asoundrc .cache .config .dbus Desktop Documents Downloads .gstreamer-0.10 .local Music Pictures Public python_games Templates .themes Videos .Xauthority .xsession-errors 

Cleaning the package listing also saves several Kbytes:

apt-get clean

At this moment we have an Raspbian Operating System which is able to run on a 4 Gbyte SD-card.

It's time to create our own installer. Shutdown the Raspberry Pi, and remove the SD card. Place a second SD-card with the Raspbian image in step 1.

After booting, connect a NTFS-formatted USB-storage (8 Gbyte) and the modified SD-card (using a SD-card reader) to the Raspberry Pi. The following partitions are automatically mounted:

/dev/sda1       7.5G  128K  7.5G   1% /media/pi/DATADISK
/dev/sdc5        30M  397K   28M   2% /media/pi/SETTINGS1
/dev/sdc6        63M   20M   44M  31% /media/pi/boot
/dev/sdc7       6.1G  2.3G  3.5G  39% /media/pi/root0

The /media/pi/root0 folder contains our modified Operating System. And the /media/pi/boot-folder contains the files needed for booting the new Operating System. We have to compress both folders, to replace the original ones (inside the Noobs installer).

Because we're using an used Linux system, we might need to clear some old log files first:

cd /media/pi/root0
> /var/log/dpkg.log
> /var/log/bootstrap.log
> /var/log/alternatives.log
> /var/log/apt/history.log
> /var/log/apt/term.log
> /var/log/apt/user.log
> /var/log/apt/kern.log
> /var/log/alternatives.log  
> /var/log/auth.log  
> /var/log/bootstrap.log  
> /var/log/daemon.log  
> /var/log/dpkg.log  
> /var/log/kern.log  
> /var/log/regen_ssh_keys.log  
> /var/log/user.log
> /var/log/messages

Now check if the following folders are empty (clean shutdown):

• proc
• sys
• dev/pts

The root.tar Linux partition contains all Linux files including all applications/software. Make a tar-archive, and compress this using maximum compression (tar -J uses the value 6)

cd /media/pi/root0
tar -cpf /media/pi/DATADISK/root.tar .
xz -9 -e /media/pi/DATADISK/root.tar

Compressing the archive takes a while on a Raspberry Pi. But it saves a lot of space:

-rw-r--r-- 1 pi pi 2170398720 Mar  9 13:43 /media/pi/DATADISK/root.tar
-rw-r--r-- 1 pi pi  665949608 Mar  9 13:43 /media/pi/DATADISK/root.tar.xz

The boot.tar partition is a FAT32 partition. This partition contains the files needed for booting the Raspberry Pi:

cd /media/pi/boot
tar -cpf /media/pi/DATADISK/boot.tar .
xz -9 -e /media/pi/DATADISK/boot.tar

The old and the new size of the tar-archive:

-rw-r--r-- 1 pi pi 20398080 Mar  9 13:33 /media/pi/DATADISK/boot.tar
-rw-r--r-- 1 pi pi 11094836 Mar  9 13:31 /media/pi/DATADISK/boot.tar.xz

Unmount the DATADISK (or shutdown the Raspberry Pi), and remove the USB-storage.

Open the Noobs installer with 7zip (just like step 1), and replace both files inside the Raspbian folder.

After replacing the boot.tar.xz and root.tar.xz files the noobs installer can be placed on a 4 Gbyte SD-card. Finally open the partitions.json-file using 7zip:

{
  "partitions": [
    {
      "label": "boot",
      "filesystem_type": "FAT",
      "partition_size_nominal": 63,
      "want_maximised": false,
      "uncompressed_tarball_size": 21
    },
    {
      "label": "root",
      "filesystem_type": "ext4",
      "partition_size_nominal": 3551,
      "want_maximised": true,
      "mkfs_options": "-O ^huge_file",
      "uncompressed_tarball_size": 3151
    }
  ]
}

Modify the values for the root-partition. (I've used the values 2653 and 2253, because we cleared 1 Gbyte). Extract all files on an empty 4Gb SD card. Insert the card in a Raspberry Pi and wait until all files are installed.

We ended with a root-file system of 2.3 Gbyte, after removing the entire GUI and some other packages.

Filesystem     1K-blocks    Used Available Use% Mounted on
/dev/root       6.1G  2.3G  3.5G  39% / 

It's time to remove entire software "sections", which are not considered "required" or "important". Else we'll never reach a 1 Gbyte install base.

java Programming python ruby

sudo apt purge bluej dh-python greenfoot idle idle-python2.7 idle-python3.4 idle3 java-common libpython-stdlib libpython2.7-minimal libpython2.7-stdlib libpython3-stdlib libpython3.4-minimal libpython3.4-stdlib libreoffice libservlet2.5-java libtcltk-ruby1.9.1 lxkeymap pypy-setuptools pypy-upstream pypy-upstream-dev python python-apt-common python-cairo python-chardet python-colorama python-dbus python-dbus-dev python-distlib python-gi python-gpiozero python-gtk2 python-html5lib python-minimal python-ndg-httpsclient python-numpy python-openssl python-picamera python-pifacecommon python-pifacedigitalio python-pil python-pip python-pkg-resources python-pyasn1 python-pygame python-requests python-rpi.gpio python-rtimulib python-sense-hat python-serial python-setuptools python-six python-spidev python-support python-talloc python-tk python-urllib3 python-wheel python-xklavier python2.7 python2.7-minimal python3 python3-apt python3-chardet python3-colorama python3-debian python3-dev python3-distlib python3-gpiozero python3-html5lib python3-minimal python3-numpy python3-pgzero python3-picamera python3-pifacecommon python3-pifacedigital-scratch-handler python3-pifacedigitalio python3-pil python3-pip python3-pkg-resources python3-pygame python3-requests python3-rpi.gpio python3-rtimulib python3-sense-hat python3-serial python3-setuptools python3-six python3-spidev python3-tk python3-uno python3-urllib3 python3-wheel python3.4 python3.4-dev python3.4-minimal ri1.9.1 ruby ruby1.9.1 ruby1.9.1-dev ruby1.9.1-examples ruby1.9.1-full ruby1.9.3 ruby2.1 rubygems-integration 

sudo apt-get autoremove

This will free 426 and 161 MByte.

Filesystem      Size  Used Avail Use% Mounted on
/dev/root       6.1G  1.5G  4.3G  26% /

debug devel fonts sound text vcs xfce

sudo apt purge alsa-base alsa-utils aspell aspell-en binutils build-essential debconf-utils desktop-file-utils dictionaries-common esound-common fontconfig fontconfig-config fonts-dejavu fonts-dejavu-core fonts-dejavu-extra fonts-freefont-ttf fonts-opensymbol fonts-roboto fonts-sil-gentium-basic freepats g++ g++-4.9 gcc gcc-4.9 gdb gdbserver git git-core gsfonts gsfonts-x11 jackd jackd2 libc6-dbg libexttextcat-data libreoffice libruby1.9.1-dbg libscsynth1 libvisual-0.4-plugins libxfce4util-bin libxfce4util-common libxfce4util6 linux-libc-dev make patch pkg-config qjackctl sgml-base squeak-plugins-scratch supercollider supercollider-common supercollider-ide supercollider-language supercollider-server supercollider-supernova timidity xfce-keyboard-shortcuts xfconf xfonts-100dpi xfonts-encodings xml-core xpdf 

sudo apt-get autoremove

This will free 350 and 152 MByte.

Filesystem      Size  Used Avail Use% Mounted on
/dev/root       6.1G  972M  4.8G  17% /

doc editors interpreters introspection metapackages mail oldlibs web

sudo apt purge claws-mail cpp cpp-4.9 curl debian-reference-common debian-reference-en dillo ed emacsen-common gir1.2-atk-1.0 gir1.2-freedesktop gir1.2-gdkpixbuf-2.0 gir1.2-glib-2.0 gir1.2-gmenu-3.0 gir1.2-gtk-3.0 gir1.2-pango-1.0 git-man javascript-common leafpad libhsqldb1.8.0-java libjs-jquery libjs-prettify libluajit-5.1-common libpango1.0-0 libpangox-1.0-0 libreoffice libreoffice-base-core libreoffice-calc libreoffice-common libreoffice-core libreoffice-draw libreoffice-impress libreoffice-java-common libreoffice-math libreoffice-style-galaxy libreoffice-writer lua5.1 luajit lxde lxde-core manpages-dev netsurf-common netsurf-gtk nodejs nodejs-legacy nodered pypy-upstream-doc python-gobject python-gobject-2 sonic-pi squeak-vm tcl8.5 tk8.5 

sudo apt-get autoremove

This will free 107 MByte.

Filesystem      Size  Used Avail Use% Mounted on
/dev/root       6.4G  853M  5.2G  14% /

Almost there, remove some large libraries

sudo apt purge gstreamer0.10-alsa gstreamer0.10-plugins-base gstreamer1.0-alsa gstreamer1.0-libav gstreamer1.0-plugins-bad gstreamer1.0-plugins-base gstreamer1.0-plugins-good gstreamer1.0-x gvfs gvfs-common gvfs-daemons gvfs-libs libaspell15 libavcodec56 libavformat56 libavresample2 libavutil54 libcairo-gobject2 libcairo2 libclucene-contribs1 libclucene-core1 libdirectfb-1.2-9 libflite1 libgl1-mesa-dri libgl1-mesa-glx libglapi-mesa libgles1-mesa libgles2-mesa libgtk-3-0 libgtk-3-bin libgtk-3-common libgtk2.0-0 libgtk2.0-bin libgtk2.0-common libmwaw-0.3-3 libopencv-calib3d2.4 libopencv-contrib2.4 libopencv-core2.4 libopencv-features2d2.4 libopencv-flann2.4 libopencv-highgui2.4 libopencv-imgproc2.4 libopencv-legacy2.4 libopencv-ml2.4 libopencv-objdetect2.4 libopencv-video2.4 libqt4-dbus sudo libqt4-network libqt4-xml libqt4-xmlpatterns libqtcore4 libqtdbus4 libqtgui4 libreoffice libruby1.9.1 libruby2.1 libwebkitgtk-3.0-0 libwebkitgtk-3.0-common

sudo apt-get autoremove

Now we're at 788 Mbyte:

Filesystem      Size  Used Avail Use% Mounted on
/dev/root       6.4G  788M  5.3G  13% /

Clean the APT-cache saves a few Mbyte.

sudo apt-get clean

Finally, the root-folder is below 700 Mbyte:

Filesystem      Size  Used Avail Use% Mounted on
/dev/root       6.4G  685M  5.4G  12% /          

Unfortunately it is not possible to install this operating system, with Noobs, using a 1 Gbyte SD-card. But the next step shows how to install this OS on a 1 GByte SD-card.

Shutdown, and boot with an other SD-card. Attach the USB storage and the SD-card from the previous step.

Check if the filesystems are mounted (df -h):

/dev/sdc7       6.4G  685M  5.4G  12% /media/pi/root0
/dev/sdc6        63M   20M   44M  31% /media/pi/boot
/dev/sdc5        30M  397K   28M   2% /media/pi/SETTINGS
/dev/sda1       7.5G  1.5G  6.1G  20% /media/pi/DATADISK

The following commands must be started as root-user:

sudo su -

Empty the logfiles:

cd /media/pi/root0
> /var/log/dpkg.log
> /var/log/bootstrap.log
> /var/log/alternatives.log
> /var/log/apt/history.log
> /var/log/apt/term.log
> /var/log/apt/user.log
> /var/log/apt/kern.log
> /var/log/alternatives.log  
> /var/log/auth.log  
> /var/log/bootstrap.log  
> /var/log/daemon.log  
> /var/log/dpkg.log  
> /var/log/kern.log  
> /var/log/regen_ssh_keys.log  
> /var/log/user.log
> /var/log/messages

Backup all Linux filesystems:

tar -cpf /media/pi/DATADISK/root1G.tar .
cd /media/pi/boot
tar -cpf /media/pi/DATADISK/boot1G.tar .
cd /media/pi/SETTINGS
tar -cpf /media/pi/DATADISK/settings1G.tar .
cd /media/pi/DATADISK

Don't forget the first recovery-partition. Remove the recovery directory for Raspbian.

mkdir /media/pi/dos
mount /dev/sdc1 /media/pi/dos
cd /media/pi/dos
tar -cpf /media/pi/DATADISK/dos1G.tar .
cd os 
rm -rf Raspbian
cd ..
tar -cpf /media/pi/DATADISK/dos1Gminimal.tar .

There is no need to compress the files, we are not going to build an installer.

-rw-r--r-- 1 pi pi  20398080 Mar  9 22:25 boot1G.tar
-rw-r--r-- 1 pi pi  29184000 Mar 10 06:48 dos1Gminimal.tar
-rw-r--r-- 1 pi pi 658565120 Mar  9 22:24 root1G.tar
-rw-r--r-- 1 pi pi     10240 Mar  9 22:25 settings1G.tar

Take a look at the partitions on the 8 Gbyte SD card. These must be made on the 1 Gbyte SD-card.

Disk /dev/sdc: 7.4 GiB, 7948206080 bytes, 15523840 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: dos
Disk identifier: 0x00031f85

Device     Boot   Start      End  Sectors   Size Id Type
/dev/sdc1          8192  1580078  1571887 767.5M  e W95 FAT16 (LBA)
/dev/sdc2       1580079 15523839 13943761   6.7G  5 Extended
/dev/sdc5       1581056  1646589    65534    32M 83 Linux
/dev/sdc6       1646592  1775615   129024    63M  c W95 FAT32 (LBA)
/dev/sdc7       1777664 15523839 13746176   6.6G 83 Linux

Remove the 8 Gbyte SD card and insert a 1 Gbyte SD card. Create the following partitions (fdisk /dev/sdb):

Disk /dev/sdb: 968.8 MiB, 1015808000 bytes, 1984000 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: dos
Disk identifier: 0x00000000

Device     Boot  Start     End Sectors   Size Id Type
/dev/sdb1         8192  137215  129024    63M  e W95 FAT16 (LBA)
/dev/sdb2       137217 1983999 1846783 901.8M  5 Extended
/dev/sdb5       139265  204799   65535    32M 83 Linux
/dev/sdb6       206848  335871  129024    63M  e W95 FAT16 (LBA)
/dev/sdb7       337920 1983999 1646080 803.8M 83 Linux

Listing with all fdisk commands used:

d (delete all partitions) 
n p 1 8192 +129024 t e 
n e 2 137217 13833999 (=default maximum)
n l 139265 +65534 t 5 83 
n l 206848 (=default) +129024 t 6 e 
n l 337920 (=default) 13833999 (=default maximum)
p w

Now create filesystems and mount them:

mkfs.msdos /dev/sdb1       
mkfs.ext4  /dev/sdb5
mkfs.msdos /dev/sdb6       
mkfs.ext4  /dev/sdb7

mkdir -p /media/pi/dos1G
mkdir -p /media/pi/settings1G
mkdir -p /media/pi/boot1G
mkdir -p /media/pi/root1G

mount /dev/sdb1 /media/pi/dos1G
mount /dev/sdb5 /media/pi/settings1G
mount /dev/sdb6 /media/pi/boot1G
mount /dev/sdb7 /media/pi/root1G

It's time to restore the files:

cd /media/pi/dos1G
tar -xpf /media/pi/DATADISK/dos1Gminimal.tar .

cd /media/pi/settings1G
tar -xpf /media/pi/DATADISK/settings1G.tar .

cd /media/pi/boot1G
tar -xpf /media/pi/DATADISK/boot1G.tar .
(ignore change owner errors)

cd /media/pi/root1G
tar -xpf /media/pi/DATADISK/root1G.tar .

With all files restored it's time to remove the SD card and use it as boot device.

Although it was very technical. I hope you liked my Instructable.