Introduction to SUSE Linux Enterprise Server for the Raspberry Pi

SUSE Linux Enterprise Server

Fabian Vogt, SUSE

This guide contains an overview of SUSE Linux Enterprise Server on the Raspberry Pi platform and will guide you through the setup procedure.

1.0 Platform Overview

To be able to use SUSE Linux Enterprise Server on Raspberry Pi, an ARM AArch64 compatible Raspberry Pi is required. SUSE Linux Enterprise Server is tested to work on a Raspberry Pi 3 Model B board.

1.1 Technical Details of the Raspberry Pi 3 Model B

The Raspberry Pi is a series of small single-board computers based on a System on a Chip (SoC) by Broadcom*, featuring various peripherals on the board.

Figure 1 Overview of the Raspberry Pi 3 Model B Connectors, © Efa / English Wikipedia / CC BY-SA 3.0

Overview of the Raspberry Pi 3 Model B connectors © Efa / English Wikipedia / CC BY-SA 3.0

Figure 2 Photo of the Raspberry Pi 3 Model B Connectors, © Evan-Amos / Own work / Public Domain

Photo of the Raspberry Pi 3 Model B connectors © Evan-Amos / Own work / Public Domain
Selected Features of the Raspberry Pi 3 Model B
CPU

The Broadcom SoC includes a quad-core ARM* Cortex*-A53 cores supporting the ARMv8 32-bit and 64-bit instruction sets. With the default configuration, it is clocked up to 1.2 GHz.

RAM

1024 MiB DDR2 memory mounted on the back of the board.

Graphics

Broadcom* VideoCore* IV providing OpenGL ES 2.0 support. Displays can be connected over HDMI or composite (TRRS jack).

Ethernet

A USB Ethernet adapter on the board provides 10/100MBit/s Ethernet.

WLAN

The BCM43438 chip supports IEEE-802.11g, IEEE-802.11b and IEEE-802.11n in the 2,4 GHz band. It also provides Bluetooth 2.0-4.1 (Low Energy).

Storage

MicroSDHC card slot

Power

The Raspberry Pi's main power source is the Micro USB connector. It is recommended to use the bundled power supply only.

USB

A total of four USB 2.0 ports is available.

Connectors

A 0.1 inch multi-function pin header is also available. Note that not all functionality of this header is exposed in SUSE Linux Enterprise Server for the Raspberry Pi.

1.2 SUSE Linux Enterprise Server 12 SP2

SUSE Linux Enterprise Server 12 SP2 is the first enterprise-class Linux operating system available free-of-charge for the Raspberry Pi. During its lifetime, customers running a registered SUSE Linux Enterprise Server for the Raspberry Pi system, will receive all released bug and security fixes, as well as feature updates.

NOTE: No commercial support available

SUSE will not provide commercial support offers via SUSE Technical Support for SUSE Linux Enterprise Server for the Raspberry Pi.

Differences Compared to Raspbian

Raspbian is the de-facto default distribution for the Raspberry Pi. The following paragraphs provide a short overview of differences between SUSE Linux Enterprise Server for the Raspberry Pi and Raspbian.

Based on Upstream Kernel

While Raspbian uses a kernel with modifications especially for the Raspberry Pi, SUSE Linux Enterprise Server for the Raspberry Pi uses the default SUSE Linux Enterprise kernel for AArch64.

AArch64 Instruction Set

SUSE Linux Enterprise Server for the Raspberry Pi is the first distribution for the Raspberry Pi using the AArch64 instruction set.

Boot Process

In Raspbian, the kernel is loaded directly. This is not supported by SUSE Linux Enterprise Server for the Raspberry Pi, where the U-Boot boot loader is used to provide an EFI boot environment. A GRUB2 EFI binary is chainloaded to provide a graphical boot screen.

Root Filesystem

SUSE Linux Enterprise Server for the Raspberry Pi uses Btrfs as file system for the root partition. compression is enabled by default for better SD-Card performance.

YaST

YaST is the installation and configuration framework for SUSE Linux Enterprise. It is popular for its easy use, flexible graphical interfaces and the capability to customize your system quickly during and after the installation. YaST can be used to configure your entire system: you can configure hardware, set up networking, manage system services and tune your security settings. All these tasks can be reached from the YaST Control Center. To start it, choose YaST in the menu or run the command xdg-su -c yast2. You will be prompted to enter the password of the root user.

Figure 3 The YaST Control Center

The YaST control center

When started, YaST shows an overview of available modules (Figure 3). Simply click an icon to open a module.

Zypper

Zypper is the package manager for SUSE Linux Enterprise. It is the tool for installing, updating and removing packages as well as managing repositories.

The general syntax for Zypper invocations is:

zypper [global-options]command[command-options][arguments] ...

NOTE: Short Command Form

For most commands, there is both a short and a long form. An overview is available with zypper --help.

Installing a package
zypper install mplayer
Removing a package
zypper remove mplayer
List available patches
zypper list-patches
Install available patches
zypper patch

NOTE: Installing Software Updates

The recommended way to install available software updates is using the YaST Online Updater. To start it, choose Online Update in Settings under Desktop Apps in the IceWM menu.

Limitations

Graphics not hardware-accelerated

X.Org hardware acceleration is disabled to improve system stability and reliability.

To enable it, comment out the following line in /etc/X11/xorg.conf.d/20-kms.conf: Option "AccelMethod" "none" by prefixing it with #.

2.0 Installation

SUSE Linux Enterprise Server for Raspberry Pi is distributed as XZ-compressed image file for MicroSD cards. This section will guide you through the process of preparing the card to the first boot. If you already have a MicroSD card containing the image, you can skip this section and go straight to Section 3.0, Booting for the First Time.

NOTE: SD Card Space Requirements

It is recommended to use a card with a capacity of at least 8 GB.

WARNING: All Data on the Card will be Lost!

By following the procedure below, all data on the SD card will be overwritten and therefore irrevocably lost! Be very careful when choosing the destination device of the image writing process!

2.1 Preparing the Card on Linux

Before and after you plug in the SD card, run the lsblk command. Between the two runs of lsblk, there should be a difference of one or more lines. The first column and first row is the name of the node representing the SD card in your system. To write the image to the card, use the dd command:

xz -cd IMAGE | dd of=/dev/SDCARDDEV bs=4096

Example 1 Writing the Image to the Card using dd

This command decompresses the image SLES-12-SP2-ARM-JeOS-raspberrypi3_aarch64-Build2.62.raw.xz to the SD card mmcblk0.

xz -cd SLES-12-SP2-ARM-JeOS-raspberrypi3_aarch64-Build2.62.raw.xz | sudo dd of=/dev/mmcblk0 bs=4096

2.2 Preparing the Card on Windows*

The following steps will guide you through the installation of the image onto the SD card on Windows. You need to meet these prerequisites:

  1. Open the downloaded image using Easy-7-Zip. Extract the file content into a folder with sufficient free space.

    7zip extraction dialog
  2. Run Win32 Disk Imager and select the extraced file as Image File. Then, choose the correct drive letter as Device. Click on Write to start the procedure.

    Win32 Disk Imager Writing Process

    NOTE: Finding the correct device

    If you are unsure which drive letter to choose from in the list, just remove the SD card and run Win32 Disk Imager again. The option that disappeared is the right target device.

2.3 Preparing the Card on macOS*

The following steps will guide you through the installation of the image onto the SD card on macOS. You need to meet these prerequisites:

  1. Open Finder at the location where the downloaded image is stored. Use the Open With selection to choose The Unarchiver instead of the default Archive utility and extract the content into a folder with sufficient free space.

    Open the Image with The Unarchiver
  2. Open a Terminal window and change into the destination directory of the uncompressed image. Enter diskutil list before and after the SD card is inserted to find out which device to use.

  3. Run diskutil unmountDisk /dev/diskX, where X is the disk number from the previous step.

  4. Run sudo dd bs=4096 if=imageFile.raw of=/dev/diskX, where X is the disk number and imageFile.raw is the name of the uncompressed image.

    sudo dd bs=4096 if=SLES-12-SP2-ARM-JeOS-raspberrypi3_aarch64-Build2.62.raw of=/dev/disk4
    Password:
    5550+0 records in
    5550+0 records out
    5819596800 bytes transferred in 1131.796649 secs (5141910 bytes/sec)
              
  5. Now unmount the disk (which is now labelled EFI) as usual.

3.0 Booting for the First Time

After insertion of the prepared MicroSD card, connect a display, ethernet and USB keyboard and mouse first, then provide power over Micro USB. After a few seconds you should be able to see a few lines of text on the screen. If that is not the case, recheck the connection to the display.

NOTE: Operation Without Mouse

YaST can be used without a mouse by only using the keyboard. Every GUI element has an accelerator configured, visible as underlined letter. To activate such an accelerator, press the letter together with Alt.

On the first boot, the system will expand to fill the entire SD card, so be patient.

3.1 Initial System Setup with YaST

After a few minutes, YaST will lead you through the initial system setup.

  1. First, the system language and keyboard layout needs to be configured. Use the drop-down boxes and click Next.

    YaST showing keyboard and language configuration on first boot
  2. Select Next on this screen.

    YaST showing a Welcome message
  3. Read the License Agreement. You need to accept the license by selecting I Agree to the License Terms and choosing Next.

    YaST displaying the license text
  4. Select the time zone either by clicking the area in the map or selecting region and zone in the drop-down boxes.

    YaST asking for the time zone

    If the time and date shown at the bottom on the screen are incorrect, setup the Network Time Protocol client by following these steps:

    1. Click Other Settings to open the NTPD configuration.

    2. Click Other Settings to synchronize date and time with NTPD.

    3. After the synchronization completed, click Accept to return to the Time and Date overview.

  5. Click Next to proceed.

  6. On this page, you can configure a default user account.

    YaST showing basic user configuration

    NOTE: Automatic Login not supported

    Automatic Login is not supported by xdm, the default display manager. Install gdm after the installation to make it work.

  7. If you chose to skip the previous step or not to set a root password, you will be asked to provide one now. Do not forget what you enter here, you will need it for administration!

    YaST asking you to set a password for the root user
  8. On this screen you need to enter your E-mail address and the registration code you received. You can also choose to Skip Registration.

    YaST asking for registration information

    NOTE: Skipping the Registration

    If you choose to skip the registration here, you will not receive updates or patches until you registered manually using YaST

  9. Click Finish to exit the setup wizard and continue the system startup.

    YaST congratulating you for finishing the initial configuration

3.2 The Desktop Environment

When the system finished booting, you will see the following login screen:

Figure 4 XDM Login Screen

XDM login screen after the system has booted

Type in the user name and password you chose during the initial configuration. The default IceWM desktop starts. By using the menu, you can start an XTerm terminal:

Figure 5 IceWM desktop

IceWM desktop after login

4.0 General System Usage

After the initial configuration procedure and the first boot of the system, you can now use various components of the system.

4.1 Bluetooth*

The Raspberry Pi has a Bluetooth* controller on-board that can be used for various purposes, like wireless keyboards, mice or audio devices.

To enable the Bluetooth* controller for use with bluetoothctl and related applications, run:

hciattach /dev/ttyAMA0 bcm43xx 921600
bcm43xx_init
Flash firmware /lib/firmware/BCM43430A1.hcd
Set Controller UART speed to 921600 bit/s
Device setup complete

You can then use hciconfig hci0 up to bring the device up and use hcitool scan to scan the environment for discoverable devices.

4.2 Compiler

It is strongly advised to use the version 6 of the GNU Compiler Collection for compiling software. It is already installed as part of the Software Development Kit. To use it, gcc-6 has to be invoked instead of gcc.

5.0 Product Documentation

This introduction only covered the most basic tasks.

5.1 Product Documentation

You can find the complete documentation for SUSE Linux Enterprise Server 12 SP2 on https://www.suse.com/documentation/sles-12/.

NOTE: Applicability of Product Documentation

Due to the Raspberry Pi being a vastly different hardware platform, not all content in the product documentation applies also to SUSE Linux Enterprise Server for the Raspberry Pi.

5.2 Self-Help Forum

SUSE has provided a self help forum where you can get answers to questions. Go to https://forums.suse.com/ and select the SLES for the Raspberry Pi forum.

7.0 GNU Free Documentation License

Copyright (C) 2000, 2001, 2002 Free Software Foundation, Inc. 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. Everyone is permitted to copy and distribute verbatim copies of this license document, but changing it is not allowed.

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ADDENDUM: How to use this License for your documents
Copyright (c) YEAR YOUR NAME.
Permission is granted to copy, distribute and/or modify this document
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with no Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts.
A copy of the license is included in the section entitled "GNU
 Free Documentation License".

If you have Invariant Sections, Front-Cover Texts and Back-Cover Texts, replace the "with...Texts". line with this:

with the Invariant Sections being LIST THEIR TITLES, with the
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If you have Invariant Sections without Cover Texts, or some other combination of the three, merge those two alternatives to suit the situation.

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