# Update device\_type for Yocto rootfs-image **URL:** \ **Category:** General Discussions\ **Tags:** yocto, beaglebone\ **Created:** [March 20, 2023, 3:08pm UTC](https://hub.mender.io/t/update-device-type-for-yocto-rootfs-image/5697 "2023-03-20T15:08:32Z")\ **Posts on this page:** 3\ **Page:** 1
**Author:** ![BGSD](https://avatars.discourse-cdn.com/v4/letter/b/aca169/32.png) [@BGSD](https://hub.mender.io/u/BGSD)\ **Post date:** [March 20, 2023, 3:08pm UTC](https://hub.mender.io/t/update-device-type-for-yocto-rootfs-image/5697/1 "2023-03-20T15:08:33Z")
# Problem Previously, we were using the `beaglebone-yocto` machine type in our Yocto build for both BeagleBone Green and BeagleBoneGreen Gateway boards. At some point we were forced to override the machine type and instead create a separate machine configuration for each of these boards. This was done using the `MACHINE_OVERRIDES` configuration variable so now we have `bbg-beaglebone-yocto` and `bbgg-beaglebone-yocto` machine types. We then build our images using bitbake ```auto bitbake mc:bbg-beaglebone-yocto:core-image-base bitbake mc:bbgg-beaglebone-yocto:core-image-base ``` Then artifacts are generated for each ```auto mender-artifact write rootfs-image \ --artifact-name bbg-os \ --device-type bbg-beaglebone-yocto \ --file tmp/deploy/images/bbg-beaglebone-yocto/out.ext4 mender-artifact write rootfs-image \ --artifact-name bbgg-os \ --device-type bbgg-beaglebone-yocto \ --file tmp/deploy/images/bbgg-beaglebone-yocto/out.ext4 ``` The problem is that our artifacts were previously generated with the `device-type` of `beaglebone-yocto` but we want to update our devices with their machine-specific artifact. # Expected Outcome What we need is some way to generate these new artifacts such that we can deploy `bbg-beaglebone-yocto` to a device that currently has the device type of `beaglebone-yocto`. This deployment should also update the device’s `Device Type` in Mender to reflect the device type of the artifact. We have attempted to solve this problem by adding `beaglebone-yocto` as an additional `--device-type` when generating our new artifacts (see command below). This allows us to install the new rootfs-image to our device however it does not actually update the `device-type` of the device in Mender. ```auto mender-artifact write rootfs-image \ --artifact-name bbgg-os \ --device-type bbgg-beaglebone-yocto \ --device-type beaglebone-yocto \ --file tmp/deploy/images/bbgg-beaglebone-yocto/out.ext4 ``` The `MENDER_DEVICE_TYPE` variable in our Yocto configuration is reporting the correct new value so that shouldn’t be the issue. (Found this using `bitbake -e`) `/var/lib/mender/device_type` on the device itself is also still reporting `beaglebone-yocto` instead of the new device type. Is there any way to solve this problem without having to manually update `/var/lib/mender/device_type` on the boards after deploying the new rootfs-image artifact? ---
**Author:** ![TheYoctoJester](https://yyz2.discourse-cdn.com/flex036/user_avatar/hub.mender.io/theyoctojester/32/1444_2.png) [@TheYoctoJester](https://hub.mender.io/u/TheYoctoJester)\ **Post date:** [March 22, 2023, 3:08pm UTC](https://hub.mender.io/t/update-device-type-for-yocto-rootfs-image/5697/2 "2023-03-22T15:08:57Z")
Hi @BGSD, this is in fact a use case that I had on my personal wish list for some time, so took the opportunity to dig into it 🙂 The easiest and most robust way is using the `script` update module. This is present by default on the device if you are using the generic Mender client installation. To be certain, check the device inventory, item `update_modules`. In a nutshell, this enables you to run a mostly arbitrary script upon installation. I used this as the script file named `change_device_type`: ```auto #!/bin/sh echo -n "device_type=fancy_new_rpi4" > /data/mender/device_type ``` and created an artifact like this: ```auto mender-artifact write module-image \ --type script \ --device-type raspberrypi4 \ -n fancy-new-rpi4 \ -f change_device_type \ -o change_device_type2.mender ``` After deployment, the device changed its type in the dashboard from `raspberrypi4` to `fancy_new_rpi4` 🎉 Take with a pinch of salt and test properly for your use case, but should be a neat solution. Greetz, Josef ---
**Author:** ![BGSD](https://avatars.discourse-cdn.com/v4/letter/b/aca169/32.png) [@BGSD](https://hub.mender.io/u/BGSD)\ **Post date:** [March 27, 2023, 8:10pm UTC](https://hub.mender.io/t/update-device-type-for-yocto-rootfs-image/5697/3 "2023-03-27T20:10:50Z")
I had to use a slightly different approach to your solution to get this to work for my use case. Since we currently have a `rootfs-image` deployed to our board with the `device_type=beaglebone-yocto`, I needed to generate two different artifacts to get this to work. So first off I have a recipe in my Yocto build for Mender update modules. The recipe looks like this: ```auto recipes-update-modules └── update-modules ├── files │ └── update-module └── update-modules_0.1.bb ``` `update-modules_0.1.bb` ```auto RDEPENDS_${PN}_append = " bash" SRC_URI = "file://update-module" S = "${WORKDIR}" FILES_${PN} += "\ ${datadir}/mender/modules/v3/update-module \ " do_install() { install -d ${D}${datadir}/mender/modules/v3 install -m 0755 update-module ${D}${datadir}/mender/modules/v3 } ``` `files/update-module` handles updating our application files and does not change anything else in our OS. So then I tried adding a new update module like you described named `update-device-type` then updated the `update-modules_0.1.bb` file to include this new script in the `SRC_URI`, the `FILES_${PN}` and the `do_install()` sections. I then generated an artifact using this new update module as follows: ```bash mender-artifact write module-image \ --type update-device-type \ -n test_update_device_type \ -t beaglebone-yocto \ -f bbgg.ext4 \ -o test_update_device_type.mender ``` However when I went to deploy this module-image artifact to my device, it failed to deploy due to the `/usr/share/mender/modules/v3/update-module` file not existing on the current image. So to work around this issue, I had to take the following approach. 1. Created three scripts in the `recipes-update-modules` recipe. - `device-type-bbg-beaglebone-yocto` - `device-type-bbgg-beaglebone-yocto` - `device-type-beaglebone-yocto` > These scripts just echo their respective `device_type` into `/data/mender/device_type`. 2. Changed permissions on each of the scripts to make them executable. ```bash chmod +x recipes-update-modules/update-modules/files/device-type* ``` 3. Added each of these scripts to the `update-modules_0.1.bb` file as described previously. ```auto RDEPENDS_${PN}_append = " bash" SRC_URI = "\ file://update-module \ file://device-type-bbg-beaglebone-yocto \ file://device-type-bbgg-beaglebone-yocto \ file://device-type-beaglebone-yocto \ " S = "${WORKDIR}" FILES_${PN} += "\ ${datadir}/mender/modules/v3/update-module \ ${datadir}/mender/modules/v3/device-type-bbg-beaglebone-yocto \ ${datadir}/mender/modules/v3/device-type-bbgg-beaglebone-yocto \ ${datadir}/mender/modules/v3/device-type-beaglebone-yocto \ " do_install() { install -d ${D}${datadir}/mender/modules/v3 install -m 0755 update-module ${D}${datadir}/mender/modules/v3 install -m 0755 device-type-bbg-beaglebone-yocto ${D}${datadir}/mender/modules/v3 install -m 0755 device-type-bbgg-beaglebone-yocto ${D}${datadir}/mender/modules/v3 install -m 0755 device-type-beaglebone-yocto ${D}${datadir}/mender/modules/v3 ``` > Looking back, I wonder if I even needed to do step #2 since I am installing these files with `0755` in the `do_install()` section here. Not really sure… 4. Build my base images. ```bash bitbake mc:bbg-beaglebone-yocto:core-image-base bitbake mc:bbgg-beaglebone-yocto:core-image-base ``` 5. Generate the `rootfs-image` artifacts for each device. ```bash mender-artifact write rootfs-image \ -n device-type-upgrade:bbg-part-1-of-2 \ -t beaglebone-yocto \ -t bbg-beaglebone-yocto \ -f core-image-base-bbg-beaglebone-yocto.ext4 \ -o device-type-upgrade-bbg-part-1-of-2.mender \ ``` > Same command repeated but replaced `bbg` with `bbgg` 6. Generate the `module-image` artifacts for each device. ```bash mender-artifact write module-image \ -T device-type-bbg-beaglebone-yocto \ -n device-type-upgrade:bbg-part-2-of-2 \ -t beaglebone-yocto \ -f core-image-base-bbg-beaglebone-yocto.ext4 \ -o device-type-upgrade-bbg-part-2-of-2.mender ``` > Same command repeated but replaced `bbg` with `bbgg` 7. Upload artifacts to Mender. 8. Deploy part 1 of artifacts to respective boards. - Board will now have the Mender module update scripts in `/usr/share/mender/modules/v3` - At this point `/data/mender/device_type` is still `beaglebone-yocto`. 9. Deploy part 2 of artifacts to respective boards. - This update actually runs the module update scripts to change `/data/mender/device_type`. At this point I can now deploy the new `rootfs-image` artifacts using the new device types. I feel like I may have overcomplicated much of this process so if there is anything that you think I did wrong then let me know. I also notice that `mender-artifact write rootfs-image` has a parameter `--script` used to specify a “state script” however I haven’t looked into those at all so I don’t know how they differ from module update scripts.