Failed to use .NET SDK agent in Azure DevOps Build Pipeline

Question

I have a ASP.NET Core 2.1 and added a nuget package of Microsoft.WindowsAzure.Storage , But after pushing the code to repo, the build pipeline occurs package error while running the build agent and is it necessary to add any other agents in build pipeline other than BUILD, RESTORE, TEST and PUBLISH.

[error]Error: The process 'C:\hostedtoolcache\windows\dotnet\dotnet.exe' failed with exit code 1

Info: Azure Pipelines hosted agents have been updated to contain .Net Core 3.x SDK/Runtime along with 2.2 & 2.1. Unless you have locked down a SDK version for your project(s), 3.x SDK might be picked up which might have breaking behavior as compared to previous versions.

This is the error it shows while running the pipeline.

Answer 1

As the error info indicates, it's not recommended to call latest 3.x sdk to restore,build,test,publish your project that targets asp .net core 2.1.

Though in most of time the build can pass, but the Publish step(task) may encounter this issue:

To resolve the issue:

We should specify the .net core sdk version we want to use before running tasks like restore,build,test,publish...

We could add a use .net core sdk task before other .net core tasks like this to pick up the .net core 2.1.x related version to do the following tasks instead of using .net core 3.x sdk:

Classic UI:

Specify 2.1.x+Include Preview Versions will pick up the latest version of 2.1 sdk.

Yaml:

In case you're using yaml format instead of classic UI format to configure the pipeline, its yaml format looks similar to this:

steps:
- task: UseDotNet@2
  displayName: 'Use .Net Core sdk 2.1.x'
  inputs:
    packageType: sdk
    version: 2.1.x
    installationPath: $(Agent.ToolsDirectory)/dotnet
    includePreviewVersions: true

Hope it helps and feel free to correct me if I misunderstand anything:)

Answer 2

I encountered the same issue with version 2.1.505 and now I am using the following configuration for variables and installer step for .NET Core in my yaml pipeline while using version 3.1.101 and it fixed my issue.

variables:
  buildConfiguration: 'Release'
  dotnetSdkVersion: '3.1.101'

steps:
- task: DotNetCoreInstaller@0
  displayName: 'Use .NET Core SDK $(dotnetSdkVersion)'
  inputs:
    version: '$(dotnetSdkVersion)'

Answer 3

The following steps worked for me:

• Add a task before restore task named "Use .Net Core"
• Specify intended sdk version ending with 'x'. For example 2.x
• Check "Include Preview Versions" option