👀 Views: 3 💬 Answers: 1 📅 Created: 2025-06-02

azure azure-functions managed-identity sql-database C#

I'm relatively new to this, so bear with me. I'm having trouble with I've been banging my head against this for hours..... I'm currently working on an Azure Function that needs to connect to an Azure SQL Database using Managed Identity, but I'm running into authentication issues. I have configured my Function to use a system-assigned managed identity, and I've granted it the necessary permissions in the SQL Database by adding it as a user with `db_datareader` and `db_datawriter` roles. However, I keep getting the following behavior when trying to query the database: ``` System.Data.SqlClient.SqlException: Login failed for user 'AzureAD\<YourManagedIdentityName>'. ``` Here's the relevant snippet of my Azure Function code: ```csharp using System; using System.Data.SqlClient; using System.Threading.Tasks; using Microsoft.AspNetCore.Mvc; using Microsoft.Azure.WebJobs; using Microsoft.Azure.WebJobs.Extensions.Http; using Microsoft.AspNetCore.Http; using Microsoft.Extensions.Logging; public static class MyFunction { [FunctionName("GetData")] public static async Task<IActionResult> Run( [HttpTrigger(AuthorizationLevel.Function, "get", Route = null)] HttpRequest req, ILogger log) { string connectionString = "Server=tcp:<YourServer>.database.windows.net;Database=<YourDatabase>;Authentication=Active Directory Managed Identity;"; using (SqlConnection conn = new SqlConnection(connectionString)) { await conn.OpenAsync(); // Your database query logic } return new OkResult(); } } ``` I've double-checked that the connection string is correctly set up and matches the Azure SQL Database's server and database names. I also confirmed that the identity is indeed assigned and has the correct roles. I've tried adding `AzureAD\` prefix to the connection string but it didn't help. Additionally, I verified that the Function App's identity is set up correctly in the Azure portal. Is there something I'm missing in the setup, or any specific configurations for .NET Core 3.1 that I should be aware of when using Managed Identity for Azure SQL Database? Any insights would be greatly appreciated! What's the best practice here? For context: I'm using C# on Ubuntu. What's the best practice here? Thanks, I really appreciate it! This is part of a larger desktop app I'm building.