AWARENESS: AIB VHD Output Change

We are making a small breaking to the VHD Output, where we will not return a SAS URI, but a BLOB URI. **We are planning to roll this change out in phases starting on May 25, 2021, and continuing into the first week of June.** Some parts of the service will return SAS and others will return SAS-less URI, so your automation/code needs to be able to handle both cases.

**Existing behavior:**

When you specify a VHD output the VHD is placed in the staging resource group, you then query the runOutput:

```
az resource show \

--ids "/subscriptions/$subscriptionID/resourcegroups/$imageResourceGroup/providers/Microsoft.VirtualMachineImages/imageTemplates/$imageTemplateName/runOutputs/$runOutputName" \

--api-version=2020-02-14 | grep artifactUri
```

This then would return a SAS URI, for example:

https://kqqtojmjy3fid5w2u3zukw1j.blob.core.windows.net/vhds/Tmp1_20210312111014.vhd?se=2021-04-11T19%3A10%3A15Z\u0026sig=xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx\u0026sp=r\u0026spr=https\u0026sr=b\u0026sv=2018-03-28

You could immediately download this.

**New behavior:**

Instead of returning the SAS URI, we will just return the BLOB URI:

https://kqqtojmjy3fid5w2u3zukw1j.blob.core.windows.net/vhds/Tmp1_20210312111014.vhd

If you wish to download them, you will need to either:

- Generate a SAS URI as a post-build step
- Use an Azure storage client to download the VHD.

Documentation for how to generate a SAS URI as a post-build step: https://github.com/Azure/azvmimagebuilder/blob/main/vhdUpdate2021.md#accomodating-the-change-example-steps-to-generate-a-sas-token-as-a-post-build-step

Please let us know if you have any questions or concerns.