RAUC Integration

Leda integrates RAUC as a reference implementation and example configuration. It allows the evaluation of the concepts, mechanisms and involved software components in an emulated, virtual environment or on physical devices.

Checking the RAUC Status

Get the current RAUC boot status:

rauc status

Example output:

root@qemux86-64:~# rauc status
=== System Info ===
Compatible:  Eclipse Leda qemu86-64
Booted from: rootfs.1 (SDV_B)

=== Bootloader ===
Activated: rootfs.1 (SDV_B)

=== Slot States ===

o [rootfs.1] (/dev/sda5, ext4, inactive)
        bootname: SDV_B
        mounted: /
        boot status: good

x [rootfs.0] (/dev/sda4, ext4, booted)
        bootname: SDV_A
        boot status: good

Forcing to boot the other slot

To manually force the device to boot into another slot, mark the current booted slot as bad, mark the other partitions as active and perform a reboot:

rauc status mark-bad booted
rauc status mark-active other
reboot now

Testing the rescue system

By marking both root slots as bad, the bootloader is supposed to boot the rescue system:

rauc status mark-bad rootfs.0
rauc status mark-bad rootfs.1
reboot now

Example output of rauc:

o [rootfs.1] (/dev/sda5, ext4, inactive)
        bootname: B
        boot status: bad

o [rootfs.0] (/dev/sda4, ext4, booted)
        bootname: A
        mounted: /
        boot status: bad


The configurations can be customized by applying or patching the following files:

  • RAUC Configuration file: meta-leda/recipes-bsp/rauc/files/qemux86-64/system.conf
  • Bootloader Configuration file: meta-leda/recipes-bsp/grub/files/grub.cfg
  • The physical disk partition configuration: meta-leda/recipes-sdv/wic/qemux86-grub-efi.wks

RAUC System Configuration

The RAUC System Configuration is the central configuration of the RAUC Update system.


compatible=Eclipse Leda qemu86-64






GRUB Bootloader Configuration

The GRUB bootloader has a configuration file which describes which partitions are bootable, which partition they are located at and a reference to RAUC’s slot name.

The configuration also contains RAUC specific logic and variables required for a proper integration. Please see the full grub.cfg in the source repository and RAUC Documentation - Integration - GRUB for details.



menuentry "SDV Slot A (OK=$SDV_A_OK TRY=$SDV_A_TRY)" {
    linux (hd0,4)/boot/bzImage root=/dev/vda4 $CMDLINE rauc.slot=SDV_A

menuentry "SDV Slot B (OK=$SDV_B_OK TRY=$SDV_B_TRY)" {
    linux (hd0,5)/boot/bzImage root=/dev/vda5 $CMDLINE rauc.slot=SDV_B

U-Boot Bootloader Configuration

Similarly to GRUB, integration of RAUC with U-Boot requires custom boot scripting. A highly detailed explaination can, again, be found in the official RAUC Documentation - Integration - U-Boot.

Meta-Leda provides such integration recipes and scripts for all U-boot based targets, for which a Leda Quickstart image is available (qemuarm64, qemuarm and rpi4-64). For example:

Note: A custom U-Boot device defconfig might be required for some devices to be integrated with RAUC. Leda Quickstart images patch the default defconfigs for qemuarm64 and qemuarm to save the U-Boot environment in a VFAT BOOT partition.

Disk Partitioning with OpenEmbedded Image Creator (WIC)

The OpenEmbedded Image Creator is used in BitBake to actually create full disk images with multiple partitions.

These disk images are machine specific and the structure of the partitions are configured in OpenEmbedded Kickstart files (*.wks).

Excerpt qemux86-grub-efi.wks

Note: The excerpt is exemplary, please see the sources for a full representation and documentation.

bootloader --ptable gpt

part --fixed-size 50M --source rawcopy --sourceparams="file=efi-boot.vfat" --fstype=vfat --label boot --active

part --fixed-size 10M --source rawcopy --sourceparams="file=grubenv.vfat" --fstype=vfat --label grubenv

part /rescue --source rootfs --fstype=ext4 --label rescue

part / --source rootfs --fstype=ext4 --label root_a

part / --source rootfs --fstype=ext4 --label root_b

part /data --fixed-size 4G --fstype=ext4 --label data