mender-convert

Mender is an open source over-the-air (OTA) software updater for embedded Linux devices. Mender comprises a client running at the embedded device, as well as a server that manages deployments across many devices.

This repository contains mender-convert, which is used to convert pre-built disk images (Debian, Ubuntu, Raspbian, etc) to a Mender compatible image by restructuring partition table and injecting the necessary files.

Currently official Raspberry Pi 3 and BeagleBone Black images are supported and this will be extended.

Getting started

To start using Mender, we recommend that you begin with the Getting started section in the Mender documentation.

Docker environment for mender-convert

In order to correctly set up partitions and bootloaders, mender-convert has many dependencies, and their version and name vary between Linux distributions.

To make using mender-convert easier, a reference setup using a Ubuntu 18.04 Docker container is provided.

You need to install Docker Engine to use this environment.

Build the mender-convert container image

To build a container based on Ubuntu 18.04 with all required dependencies for mender-convert, copy this directory to your workstation and change the current directory to it.

Then run

./docker-build

This will create a container image you can use to run mender-convert.

Use the mender-convert container image

Create a directory input under the directory where you copied these files (docker-build, docker-mender-convert, etc.):

mkdir input

Then put your raw disk image into input/, e.g.

mv ~/Downloads/2018-11-13-raspbian-stretch.img input/2018-11-13-raspbian-stretch.img

You can run mender-convert from inside the container with your desired options, e.g.

DEVICE_TYPE="raspberrypi3"
RAW_DISK_IMAGE="input/2018-11-13-raspbian-stretch.img"

ARTIFACT_NAME="2018-11-13-raspbian-stretch"
MENDER_DISK_IMAGE="2018-11-13-raspbian-stretch.sdimg"
TENANT_TOKEN="<INSERT-TOKEN-FROM Hosted Mender>"

./docker-mender-convert from-raw-disk-image                      \
            --raw-disk-image $RAW_DISK_IMAGE                     \
            --mender-disk-image $MENDER_DISK_IMAGE               \
            --device-type $DEVICE_TYPE                           \
            --artifact-name $ARTIFACT_NAME                       \
            --bootloader-toolchain arm-buildroot-linux-gnueabihf \
            --server-url "https://hosted.mender.io"              \
            --tenant-token $TENANT_TOKEN

By default conversion in containter uses GCC 7.3.0 bootlin toolchain tuned for ARMv6 architecture (especially for ARM1176(F)-S single-core processor). The aim of that is to provide a support for the Raspberry Pi Zero W development board.

ARMv7 is backward compatible with ARMv6, so binaries compiled for ARMv6 should also work on ARMv7.

Note that the default Mender client is the latest stable and cross-compiled for generic ARM boards, which should work well in most cases. If you would like to use a different Mender client, place it in input/ and adjust the --mender-client argument.

Conversion will take 10-15 minutes, depending on your storage and resources available. You can watch output/build.log for progress and diagnostics information.

After it finishes, you can find your images in the output directory on your host machine!

Known issues

• An issue for Raspberry Pi Zero W has been spotted with the mender-convert tool version 1.1.0. After an initial boot, having last partition resized to the end of the SD card, the correct device tree cannot be found. As a result the boot cannot succeed. For more information and current status, see issue tracker.
• If building U-boot fails with:

     D	scripts/Kconfig
     input in flex scanner failed
     ....
     include/linux/kconfig.h:4:32: fatal error: generated/autoconf.h: No such file or directory
     #include <generated/autoconf.h>

you might be using a case-sensitive filesystem which is not supported. Case-sensitive filesystems are typically used on OSX (Mac) and Windows but you can also run in to this on Linux if running on a NTFS formatted partition.

For details see this discussion

Contributing

We welcome and ask for your contribution. If you would like to contribute to Mender, please read our guide on how to best get started contributing code or documentation.

License

Mender is licensed under the Apache License, Version 2.0. See LICENSE for the full license text.

Security disclosure

We take security very seriously. If you come across any issue regarding security, please disclose the information by sending an email to security@mender.io. Please do not create a new public issue. We thank you in advance for your cooperation.

Connect with us

• Join the Mender Hub discussion forum
• Follow us on Twitter. Please feel free to tweet us questions.
• Fork us on Github
• Create an issue in the bugtracker
• Email us at contact@mender.io
• Connect to the #mender IRC channel on Freenode