[SOLVED] Managed Identity for Blob-Triggered Azure Function: "No such host is known"

Managed Identity for Blob-Triggered Azure Function: "No such host is known"

I am getting the following errors in my Blob Triggered Azure Function App:

Azure.Core: No such host is known. (examplestorage.blob.core.windows.net:443). System.Net.Http: No such host is known. (examplestorage.blob.core.windows.net:443). System.Net.Sockets: No such host is known.

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I have an Azure Function app which is Blob triggered:

[Function("ExampleFunction")]
public async Task Run([BlobTrigger("%BlobPath%", Connection = "AzureWebJobsStorage")] Stream myBlob, string name)

Previously I was using a connection string to connect to the Storage Account, however I want to update this to Managed Identity. I have followed this tutorial here:

https://learn.microsoft.com/en-us/azure/azure-functions/functions-bindings-storage-blob-trigger?tabs=python-v2%2Cisolated-process%2Cnodejs-v4%2Cextensionv5&pivots=programming-language-csharp#connections

I have added the following attributes in Environment Variables:

AzureWebJobsStorage__accountName = examplestorage
AzureWebJobsStorage__blobServiceUri = https://examplestorage.blob.core.windows.net
AzureWebJobsStorage__credential = managedidentity
AzureWebJobsStorage__queueServiceUri = https://examplestorage.queue.core.windows.net

Instead of Connection = AzureWebJobsStorage, I have also tried using something like Connection = BlobTriggerConnection, then adding the following Environment Variables:

BlobTriggerConnection__blobServiceUri = https://examplestorage.blob.core.windows.net
BlobTriggerConnection__credential = managedidentity
BlobTriggerConnection__queueServiceUri = https://examplestorage.queue.core.windows.net

However this did not work for me either.

I am using a dedicated App Service Plan (ASP): Premium v3 P2V3 (I have seen it does not work with consumption or elastic premium plans)

I am also using the following:

<PackageReference Include="Microsoft.Azure.Functions.Worker.Extensions.Storage" Version="6.6.0" />
<PackageReference Include="Microsoft.Azure.Functions.Worker.Extensions.Storage.Blobs" Version="6.6.0" />
<PackageReference Include="Microsoft.Azure.Functions.Worker.Extensions.Storage.Queues" Version="5.5.0" />

I have granted the following role assignments to the Function App to the Storage Account:

Storage Account Contributor
Storage Blob Data Owner
Storage Queue Data Contributor

I have also seen that it does not work with the connection strings:

WEBSITE_CONTENTAZUREFILECONNECTIONSTRING
WEBSITE_CONTENTSHARE

My function app did have these app settings, and according to this discussion here, once the settings have been set there isn't a way to use Managed Identity. So, I have also tried re-deploying the Function App and ensured these variables were not ever present. However I still get the same error as I am getting in the original function app. https://techcommunity.microsoft.com/t5/apps-on-azure-blog/use-managed-identity-instead-of-azurewebjobsstorage-to-connect-a/ba-p/3657606

Solution

There was a very small typo in the storage account name. This has been fixed.