iotedge deployment set module environment value per device for multidevice deployment

Question

Looking for workarounds here

I am creating a single edge deployment with target condition tags.environment = 'pilot'. This target condition results to multiple edge devices.

Requirement: I need to have unique module environment value per device.
Problem : I only have one deployment.json in this case and can only set environment value once that will apply for all devices->modules.

Straight alternative : I can use individual deployments targeting individual devices. Allowing me to have separate deployment jsons which can have unique module environment value per device. This alternative is doable; but preferring a deployment targeting multiple edge devices.

Answer 1

Hello @GopikrishnanBahuleyan-2250 ,
Want to be sure that you have looked at the following doc?:

• Understand IoT Edge automatic deployments for single devices or at scale

Specifically the section Layered deployment may be the solution for your scenario.

"Layered deployments are automatic deployments that can be combined together to reduce the number of unique deployments that need to be created. Layered deployments are useful in scenarios where the same modules are reused in different combinations in many automatic deployments."

Thank you.

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Answer 2

For this odd need, I think Docker CMD could be choice. And I am trying to use it. This would give an option to set a new value to an environment variable and module instance could use it.

Answer 3

Hi,

I'm hurting the same issue. I'm using layered deployment for multi-devices.

I need my deployment to use device specific values.

I cannot use the createOptions from the deployment since it's not device specific.

Is there a way to inject ENV variables in a device? In the /etc/iotedge/config.yaml?

Where come from those ENV variables?
IOTEDGE_DEVICEID
IOTEDGE_GATEWAYHOSTNAME
IOTEDGE_IOTHUBHOSTNAME
...

Can I add one?

Or Is it possible to use device's tags in a module?

Thanks for you help!