Raspberry Pi 3 (64 bit) on RPI4 application

Product support
1

Hi,

We’ve an app, created for the Raspberry Pi 4 (64 bit), but we’d like to support older Raspberry Pi’s that are already running in the field. So I downloaded the Raspberry Pi 3 (64-bit) image, configured it so that it’s connected to the RPI4 application, and (with some small changes) all went well!

However, I created a production image where I added the os.ssh-keys option to the config.json, and there the deviceType changed to raspberrypi4-64, because the application is configured for that device type.

So far, everything runs well on both the RPI4 as the RPI3, but I just wanted to know if this can cause any problems? We’ll test our releases on both devices, so the application itself won’t be a problem.

Thanks!

4

Hi @bversluijs, can you clarify how you got there? For reference I tried to replicate following this steps:

  1. Create an application with default device type: Raspberry Pi 4
  2. Add a new device to the app with device type Raspberry Pi 3 (using 64bit OS)
  3. Download balenaOS

Upon inspecting the contents of config.json I see: "deviceType":"raspberrypi3-64"

Is this not the case for you? I suspect your workflow is slightly different but not sure how it differs, please let me know!

6

Hi Tomas,

I’m using openBalena, so I’m using the Balena CLI as follows:

balena configure os <path-to-image> --app <app>

The config.json file had raspberrypi3-64 in it before I configured it via the CLI, but after configuring it, it changed to raspberrypi4-64. The device-type.json stayed raspberrypi3-64.

I’m using Balena CLI version 12.38.4 (haven’t updated my production environment of openBalena yet)

Edited, because my first response was short, not detailed (was on my phone)

7

Thank you for clarifying your steps, that’s very helpful!

From what I can understand the CLI is using details from the provided app (--app <app>) to populate config.json so it’s inheriting the default application type of the app, which is raspberrypi4-64 in this case.

Fortunately the real source of truth for a device type is device-type.json which is unchanged from raspberrypi3-64 as you noticed so the behaviour of your device and application should be unaffected.

That being said, I find this behaviour a little odd so I’m going to bring it up for discussion internally to confirm it’s expected and what the plans are going forward regarding config.json vs device-type.json.

Thank you for bringing this to our attention!

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