There is a variety of client-only solutions for installing update artifacts to embedded Linux devices, such as SWupdate or RAUC which do not offer a remote management solution. Those can be wrapped in an Update Module to enable OTA deployments, while keeping known good working integrations intact.

Example use-cases:

  • Brownfield migration of existing device fleets using a client-only update solution
  • Wrapping a custom flashing solution, as sometimes required for special hardware

This Update Module provides a sample implementation to deploy SWUpdate artifacts using Mender, but it can be easily adapted to other client solutions.


Module name swu
Supports rollback no
Requires reboot configurable
Artifact generation script no
Full operating system updater no
Source code https://github.com/mendersoftware/mender-update-modules/master/swu
Maintainer josef.holzmayr@northern.tech

Please be aware that Mender Update modules are meant to update parts of the operating system and if not configured properly they could potentially delete parts or even the full operating system. Always inspect the code carefully and only test modules on device that you can recover easily.

It is not recommended to install a Mender Artifact on your workstation

Prepare the device

This section describes how to setup your target device, i.e. the device to be updated. This will also be referred to as the device environment.

All commands outlined in this section should be run in the device environment.


This update module has the following prerequisites for the device environment:

This Update Module has the following prerequisites for the development environment:

Install the Update Module

Download the latest version of this Update Module by running:

mkdir -p /usr/share/mender/modules/v3 && wget -P /usr/share/mender/modules/v3 https://raw.githubusercontent.com/mendersoftware/mender-update-modules/master/swu/module/swu && chmod +x /usr/share/mender/modules/v3/swu

Prepare the development environment on your workstation

This section describes how to set up your development environment on your workstation.

All commands outlined in this section should be run in the development environment.

Create artifact

To download swu-artifact-gen, run the following:

wget https://raw.githubusercontent.com/mendersoftware/mender-update-modules/master/install_snap/module-artifact-gen/install_snap-artifact-gen && chmod +x swu-artifact-gen

Generate Mender Artifacts using the following command:

./swu-artifact-gen \
    --artifact-name ${ARTIFACT_NAME} \
    --device-type ${DEVICE_TYPE} \
    <name of swu file(s)> ...

Optional reboot

The SWU Update Module supports rebooting after artifact installation. If this is required for the packaged SWU file(s), add the --reboot flag to the swu-artifact-gen invocation.

Possible future improvements

  • rollback support
  • automatic determination of metadata from SWU file(s)
  • enforced ordering of multiple SWUs
  • streaming support

You can either deploy this Artifact in managed mode with the Mender server (upload it under Releases in the server UI) or by using the Mender client only in Standalone deployments.

Artifact technical details

  • The artifact can include an arbitrary number of *.swu files, but does not explicitly guarantee an installation order. The swupdate invocation uses a *.swu wildcard.

Creating a sample .swu file

In order to test this Update Module, having a device independent swu artifact is useful. To create one, you need the following:

A payload file. We will use this swu-demo.txt as an example:

Demo payload for the Mender SWU Update Module!

The sw-description file:

software =
    description = "Demo for Mender SWU Update Module"

    hardware-compatibility: ["1.0"];

    files: (
            filename = "swu-demo.txt";
            path = "/opt/swu-demo.txt";
			properties = {
				create-destination = "true";

An swu file is at its heart a cpio archive, with the sw-description file coming first. You can create one using the following script:



echo "creating SWU artifact ${OUTFILE}"

if [ -f "$OUTFILE" ]; then
    echo "$OUTFILE already exists, moving to $OUTFILE.bak"

FILES="sw-description swu-demo.txt"

for i in $FILES;do
    echo $i;done | cpio -ov -H crc > ${OUTFILE}

The resulting swu-demo_1.0.swu can be used for the swu-artifact-gen script as described above.

@TheYoctoJester thanks for sharing this, I think this could be super useful.


Full operating system updater no

Is there a limitation which means this couldn’t be used to update the full operating system if the .swu is capable of this? I’m wondering about making a small wrapper for this around the demo at GitHub - OE4T/tegra-demo-distro: Reference/demonstration distro for meta-tegra for Jetpack 5 and later mender support instead of the more complicated integration at fix: Tegra, Jetpack 5: add Jetson as working target by mwest90 · Pull Request #19 · OE4T/meta-mender-community · GitHub

Hi @dwalkes,

Thanks for the heads up! The “full operating system updater: no” indicates that the flow of update-reboot-commit which involves SWUpdate along the way has not been tested. Technically it is certainly possible, but as root filesystem streaming is also not supported in this incarnation, I would not consider it a good strategy for new products.

The idea of this Update Module is being able to augment and retrofit existing products that are already using SWUpdate, for actively developed solutions I would not consider it a recommended choice.