Plan for Change - Part 3: Azure Sphere February Release
Published Jan 22 2020 04:30 PM 2,337 Views
Steel Contributor

This is the third in a series of posts about changes coming in the February release of Azure Sphere.  

As we mentioned earlier, we are making a number of enhancements to our OS and SDK to further strengthen the defense-in-depth for devices at customer sites and ensure supportability from GA onward. Although our goal is to avoid the introduction of breaking changes and incompatibility between releases, our transition from Public Preview to the General Availability (GA) release requires several important updates. In a few situations, you will need to make changes to ensure your devices and applications continue to work as intended. Thank you very much for your support in Public Preview and for helping us deliver a great GA product.  


You can find a summary of Upcoming Changes in the Azure Sphere documentation. 


TLS versions 

Libcurl on Azure Sphere supports TLS 1.2 and has deprecated TLS 1.0 and TLS 1.1 in alignment with the broader Microsoft TLS security strategy. 


Update your apps to use CMake 

Since the 19.10 SDK release, all new Azure Sphere apps are built using CMake by default. CMake is a cross-platform build system that you can use for all your development: for high-level apps and real-time capable apps; for Windows and Linux; and for development in Visual Studio, Visual Studio Code, or the command line. 


The February SDK release will no longer support the use of Visual Studio projects (.vcxproj and msbuild). You will need to convert any existing apps to build with CMake 


Return to earlier Public Preview versions unavailable 

As part of our defense-in-depth against rollback attacks, recovery and rollback to earlier Public Preview versions of the Azure Sphere OS will be unavailable on devices that have already updated to the February release. 


This means that you will be unable to recover device to an earlier Public Preview release after it has received the February update. The February release will become the earliest release that can be installed on the device 


The updated OS will be available on the Retail Evaluation OS feed for 14 days before its release on the Retail OS feed. The effect on your devices depends on their device group and the OS feed they receive:  

  • Devices that receive the Retail Evaluation OS Feed: Devices in their product’s Field Test OS Evaluation group, Production OS Evaluation groupor any other group that receives the Retail Evaluation OS Feed will receive the February OS release 14 days before its Retail release. Devices in these groupwill be unable to recover to any earlier release after the February release is installed. However, such devices will continue to receive application updates if their device group enables application updates.  

 If you move a device that has the February Retail Evaluation OS to a device group that receives the Retail OS feed, the OS on the device will not revert to the 19.11 release. Once the device has the February release, it cannot recover to or cloud-load an earlier release. In addition, the device will not be able to receive application updates until the retail evaluation period has ended and the February OS update is available on the Retail OS feed. 

  • Devices in the Development device group: The default feed for the Development device group has been changed to Retail OS instead of Retail Evaluation OS 

To ensure that your devices receive the updated OS at the appropriate time, and to avoid any disruptions in your work flow, we strongly urge you to take the following steps now: 

  1. Verify that your Development device group receives the Retail OS feed, as described in Default device groups and OS feeds. 
  2. Set up additional devices for Retail Evaluation. 
  3. Plan to verify your applications with the Retail Evaluation OS feed as soon as it is available. 

February SDK release required with OS 

The February OS release requires the February SDK release; earlier SDKs will not work with the February OS release. The February SDK is required to unlock a device that is running the February OS release and to recover the device to the February OS release, among other features 

When we release the Retail Evaluation OS, we will also make available an evaluation version of the new SDK to enable verification of the Retail Evaluation OS. You can also use this early version of the February SDK with the 19.11 OS release. When we release the Retail OS, we will release the final February SDK and the documentation, so that you can develop applications that use the new February features.  


Verify your apps with the Retail Evaluation OS feed 

Please plan to verify your scenarios against the February OS release as soon as it is available on the Retail Evaluation OS feed. Set up devices for OS evaluation in the online documentation provides additional information on how to assign devices to an evaluation group. This is the best way to ensure compatibility with the forthcoming OS before its Retail release. Be aware that you might need to modify your procedures or applications. We will provide additional information about upcoming changes through the IoT blog and in the Azure Sphere online documentation as GA nears. 

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‎Jan 22 2020 04:29 PM
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