[bug] error NU1301 (Unable to load the service index for source https://api.nuget.org/v3/index.json.) when I am trying to create any .NET Application in Ubuntu 20.04

[sevens7xix]

NuGet Product Used

dotnet.exe

Product Version

dotnet-sdk-7.0.202

Worked before?

No response

Impact

None

Repro Steps & Context

1. Step one keep Ubuntu 20.04 with all its dependencies updated
2. Try to create any project that needs additional dependencies like https://learn.microsoft.com/en-us/aspnet/core/tutorials/first-web-api?view=aspnetcore-3.1&tabs=visual-studio-code#create-a-web-project-3 or https://learn.microsoft.com/en-us/azure/azure-functions/create-first-function-vs-code-csharp?tabs=in-process#create-an-azure-functions-project
3. That it, when omnisharp or the dotnet sdk try to restore/build/run the project the following exception its handled error NU1301: Unable to load the service index for source https://api.nuget.org/v3/index.json.

Verbose Logs

(in) RestoreGraphItems Count '7' (TaskId:39)
                     (in) RestoreDisableParallel 'False' (TaskId:39)
                     (in) RestoreNoCache 'False' (TaskId:39)
                     (in) RestoreIgnoreFailedSources 'False' (TaskId:39)
                     (in) RestoreRecursive 'True' (TaskId:39)
                     (in) RestoreForce 'False' (TaskId:39)
                     (in) HideWarningsAndErrors 'False' (TaskId:39)
                     (in) RestoreForceEvaluate 'False' (TaskId:39)
                     (in) RestorePackagesConfig 'False' (TaskId:39)
                     X.509 certificate chain validation will use the fallback certificate bundle at '/usr/share/dotnet/sdk/7.0.202/trustedroots/codesignctl.pem'. (TaskId:39)
                     X.509 certificate chain validation will use the fallback certificate bundle at '/usr/share/dotnet/sdk/7.0.202/trustedroots/timestampctl.pem'. (TaskId:39)
                     Running restore with 4 concurrent jobs. (TaskId:39)
                     Reading project file /home/saroui/Documents/sample-app/TodoApi/TodoApi.csproj. (TaskId:39)
                     The restore inputs for 'TodoApi' have changed. Continuing restore. (TaskId:39)
                     Restoring packages for /home/saroui/Documents/sample-app/TodoApi/TodoApi.csproj... (TaskId:39)
                     Restoring packages for .NETCoreApp,Version=v7.0... (TaskId:39)
11:06:51.525     1>/home/saroui/Documents/sample-app/TodoApi/TodoApi.csproj : error NU1301: Unable to load the service index for source https://api.nuget.org/v3/index.json.
11:06:51.533     1>/home/saroui/Documents/sample-app/TodoApi/TodoApi.csproj : error NU1301: Unable to load the service index for source https://api.nuget.org/v3/index.json.
                     Checking compatibility of packages on net7.0. (TaskId:39)
                     All packages and projects are compatible with net7.0. (TaskId:39)
                     Committing restore... (TaskId:39)
                     Writing assets file to disk. Path: /home/saroui/Documents/sample-app/TodoApi/obj/project.assets.json (TaskId:39)
                     Writing cache file to disk. Path: /home/saroui/Documents/sample-app/TodoApi/obj/project.nuget.cache (TaskId:39)
                     Persisting dg to /home/saroui/Documents/sample-app/TodoApi/obj/TodoApi.csproj.nuget.dgspec.json (TaskId:39)
                     Failed to restore /home/saroui/Documents/sample-app/TodoApi/TodoApi.csproj (in 326 ms). (TaskId:39)
                      (TaskId:39)
                     NuGet Config files used: (TaskId:39)
                         /home/saroui/.nuget/NuGet/NuGet.Config (TaskId:39)
                      (TaskId:39)
                     Feeds used: (TaskId:39)
                         https://api.nuget.org/v3/index.json (TaskId:39)
                   Done executing task "RestoreTask" -- FAILED. (TaskId:39)
11:06:51.652     1>Done building target "Restore" in project "TodoApi.csproj" -- FAILED.: (TargetId:42)
11:06:51.658     1>Done Building Project "/home/saroui/Documents/sample-app/TodoApi/TodoApi.csproj" (Restore target(s)) -- FAILED.
Deferred Messages
11:06:51.659     0>
Detailed Build Summary
======================
     (TaskId:0)
                     
                     ============================== Build Hierarchy (IDs represent configurations) =====================================================
                     Id                  : Exclusive Time   Total Time   Path (Targets)
                     ----------------------------------------------------------------------------------------------------------------------------------- (TaskId:0)
                     0                   : 1.627s           1.932s       /home/saroui/Documents/sample-app/TodoApi/TodoApi.csproj (Restore)  (TaskId:0)
                     | 1                 : 0.077s           0.077s       /home/saroui/Documents/sample-app/TodoApi/TodoApi.csproj (_IsProjectRestoreSupported)  (TaskId:0)
                     | 2                 : 0.009s           0.009s       /home/saroui/Documents/sample-app/TodoApi/TodoApi.csproj (_GenerateRestoreProjectPathWalk)  (TaskId:0)
                     | 3                 : 0.196s           0.196s       /home/saroui/Documents/sample-app/TodoApi/TodoApi.csproj (_GenerateRestoreGraphProjectEntry)  (TaskId:0)
                     . 4                 : 0.021s           0.021s       /home/saroui/Documents/sample-app/TodoApi/TodoApi.csproj (_GenerateProjectRestoreGraph)  (TaskId:0)
                     
                     ============================== Node Utilization (IDs represent configurations) ====================================================
                     Timestamp:            1        Duration   Cumulative
                     ----------------------------------------------------------------------------------------------------------------------------------- (TaskId:0)
                     638168260097250049:   0        0.905s     0.905s .................. (TaskId:0)
                     638168260106301983:   1        0.078s     0.983s . (TaskId:0)
                     638168260107081071:   0        0.041s     1.024s  (TaskId:0)
                     638168260107492220:   2        0.010s     1.034s  (TaskId:0)
                     638168260107587607:   0        0.019s     1.053s  (TaskId:0)
                     638168260107776373:   3        0.196s     1.249s ... (TaskId:0)
                     638168260109739325:   0        0.003s     1.252s  (TaskId:0)
                     638168260109766418:   4        0.021s     1.273s  (TaskId:0)
                     638168260109978266:   0        0.662s     1.935s ............. (TaskId:0)
                     -----------------------------------------------------------------------------------------------------------------------------------
                     Utilization:          100.0    Average Utilization: 100.0 (TaskId:0)

Project Evaluation Performance Summary:
      837 ms  /home/saroui/Documents/sample-app/TodoApi/TodoApi.csproj   2 calls

Project Performance Summary:
     1333 ms  /home/saroui/Documents/sample-app/TodoApi/TodoApi.csproj   6 calls
               1107 ms  Restore                                    1 calls
                  2 ms  _IsProjectRestoreSupported                 2 calls
                  8 ms  _GenerateRestoreProjectPathWalk            1 calls
                195 ms  _GenerateRestoreGraphProjectEntry          1 calls
                 21 ms  _GenerateProjectRestoreGraph               1 calls

Target Performance Summary:
        0 ms  _GenerateRestoreProjectPathItemsCurrentProject   1 calls
        0 ms  _GenerateProjectRestoreGraph               1 calls
        0 ms  _GetRestoreSettingsCurrentProject          1 calls
        0 ms  _GenerateRestoreDependencies               1 calls
        0 ms  _GenerateProjectRestoreGraphCurrentProject   1 calls
        0 ms  _GenerateRestoreGraphProjectEntry          1 calls
        0 ms  _CheckForObsoleteDotNetCliToolReferences   1 calls
        0 ms  _GetRestoreTargetFrameworkOverride         1 calls
        0 ms  _CheckForUnsupportedCppNETCoreVersion      2 calls
        0 ms  _CheckForLanguageAndFeatureCombinationSupport   1 calls
        0 ms  _GetProjectJsonPath                        1 calls
        0 ms  _GetRestoreSettingsPerFramework            1 calls
        0 ms  _CheckForUnsupportedNETCoreVersion         2 calls
        0 ms  _GetRestoreSettingsOverrides               1 calls
        0 ms  _IsProjectRestoreSupported                 1 calls
        1 ms  CollectFrameworkReferences                 1 calls
        1 ms  _GenerateRestoreSpecs                      1 calls
        1 ms  _GenerateRestoreProjectPathItems           1 calls
        1 ms  CollectCentralPackageVersions              1 calls
        1 ms  _CollectTargetFrameworkForTelemetry        1 calls
        2 ms  _GenerateRestoreProjectPathItemsPerFramework   1 calls
        3 ms  ApplyImplicitVersions                      1 calls
        3 ms  _GenerateDotnetCliToolReferenceSpecs       1 calls
        3 ms  _GetRestoreTargetFrameworksOutput          1 calls
        3 ms  _GenerateRestoreProjectSpec                1 calls
        3 ms  CollectPackageReferences                   1 calls
        3 ms  CheckForImplicitPackageReferenceOverrides   1 calls
        4 ms  _GenerateRestoreProjectPathWalk            1 calls
        5 ms  CollectPackageDownloads                    1 calls
        7 ms  _GenerateProjectRestoreGraphPerFramework   1 calls
        8 ms  _GetRestoreProjectStyle                    1 calls
       11 ms  UpdateAspNetToFrameworkReference           1 calls
       25 ms  _LoadRestoreGraphEntryPoints               1 calls
       30 ms  _GetAllRestoreProjectPathItems             1 calls
       34 ms  _GetRestoreSettings                        1 calls
      125 ms  ProcessFrameworkReferences                 1 calls
      153 ms  _FilterRestoreGraphProjectInputItems       1 calls
      227 ms  _GenerateRestoreGraph                      1 calls
      652 ms  Restore                                    1 calls

Task Performance Summary:
        1 ms  GetRestorePackageDownloadsTask             1 calls
        1 ms  AllowEmptyTelemetry                        1 calls
        1 ms  GetRestoreFrameworkReferencesTask          1 calls
        1 ms  ApplyImplicitVersions                      1 calls
        1 ms  GetRestoreProjectReferencesTask            1 calls
        1 ms  CheckForDuplicateFrameworkReferences       1 calls
        1 ms  GetRestorePackageReferencesTask            1 calls
        2 ms  GetRestoreDotnetCliToolsTask               1 calls
        2 ms  GetProjectTargetFrameworksTask             1 calls
        2 ms  NuGetMessageTask                           1 calls
        2 ms  ConvertToAbsolutePath                      2 calls
        2 ms  CheckForImplicitPackageReferenceOverrides   1 calls
        3 ms  Message                                    3 calls
        4 ms  GetRestoreProjectStyleTask                 1 calls
        5 ms  CheckIfPackageReferenceShouldBeFrameworkReference   2 calls
        5 ms  WarnForInvalidProjectsTask                 1 calls
        7 ms  RemoveDuplicates                           5 calls
        8 ms  CheckForDuplicateNuGetItemsTask            3 calls
       31 ms  ResolveAppHosts                            1 calls
       33 ms  GetRestoreSettingsTask                     1 calls
       89 ms  ProcessFrameworkReferences                 1 calls
      366 ms  MSBuild                                    6 calls
      651 ms  RestoreTask                                1 calls

Build FAILED.

                   "/home/saroui/Documents/sample-app/TodoApi/TodoApi.csproj" (Restore target) (1) ->
                   (Restore target) -> 
                     /home/saroui/Documents/sample-app/TodoApi/TodoApi.csproj : error NU1301: Unable to load the service index for source https://api.nuget.org/v3/index.json.
                     /home/saroui/Documents/sample-app/TodoApi/TodoApi.csproj : error NU1301: Unable to load the service index for source https://api.nuget.org/v3/index.json.

    0 Warning(s)
    2 Error(s)

[kartheekp-ms]

May be related to #5358. Is there any proxy configured in the environment?

Bing AI Chat suggests, you can check the proxy settings via the command line using the following steps:

- Open the Terminal application.
- Type the command "env | grep -i proxy" and press Enter. This will display the proxy settings for your system.
- If you see any proxy-related environment variables such as http_proxy, https_proxy, ftp_proxy, etc., it means a proxy is configured for your system.
- You can also check the contents of the /etc/environment file and the /etc/apt/apt.conf.d/proxy file to view the proxy settings in Ubuntu.

[sevens7xix]

Hey there, Thanks to answer to this issue, actually I check issue #5358 before and try everything suggested there but nothing solved the problem. Besides I checked "env | grep -i proxy" and "/etc/apt/apt.conf.d/proxy " and there isn't any proxy configured on my enviroment.

If it helps to unfog this problem, curl https://api.nuget.org/v3/index.json works perfectly and also I can access to the URL from multiple browsers without any problem.

I am going to stay tuned, Thank you very much beforehand!.

[zivkan]

Unfortunately NuGet isn't showing inner exceptions on these "unable to get service index" errors, making it hard to guess what the root cause was: #12530

From my own testing, dotnet add package does show the inner exception. So, can you please try dotnet add package NuGet.Protocol (or any other package you like), and you should see what the cause of the connection failure is.

[sevens7xix]

Thank you very much, now I can see what is the cause of the connection issue and its looks like some incompatibility with the kernel of my environment

info : X.509 certificate chain validation will use the fallback certificate bundle at '/usr/share/dotnet/sdk/7.0.202/trustedroots/codesignctl.pem'.
info : X.509 certificate chain validation will use the fallback certificate bundle at '/usr/share/dotnet/sdk/7.0.202/trustedroots/timestampctl.pem'.
info : Adding PackageReference for package 'NuGet.Protocol' into project '/home/saroui/Documents/sample-app/TodoApi/TodoApi.csproj'.
error: Unable to load the service index for source https://api.nuget.org/v3/index.json.
error:   The format of value '(Linux 6.2.10-1-liquorix-amd64 #1 ZEN SMP PREEMPT_DYNAMIC liquorix 6.2-13ubuntu1~focal (2023-04)' is invalid.

In theory its the last update of the kernel, and I just followed the steps on MS Docs to install de .NET SDK present on my environment. I would be glad to know if there is something I can do to fix the issue locally.

[zivkan]

This was a known issue, first reported a few months ago, but has been fixed in the main branch

• [Bug]: Custom kernel breaks nuget #11995

The fix will be part of NuGet 6.6, which isn't out yet. But if you can use a preview .NET SDK 7.0.3xx, it should work. If you're using a version of the .NET SDK that is available as part of Ubuntu's package repository, that's using what .NET calls "source build", and for reasons I don't understand they limit to the 1xx versions of the SDK, which means it won't contain NuGet's fix until version 8.0.1xx. But if you can use the Microsoft package feed, then you can get newer versions of the .NET SDK (but possibly not previews): https://learn.microsoft.com/en-us/dotnet/core/install/linux-ubuntu

[sevens7xix]

Thank you, could you please show me how to get the .NET SDN 7.0.3xx because the latest release of .NET 7.0.5 includes .NET SDK 7.0.203, but I don't see any trace of the nightly builds.

Thank you beforehand!

[kartheekp-ms]

I don't see any trace of the nightly builds.

https://github.com/dotnet/installer/blob/main/README.md#table

I am closing this as a duplicate of #11995 that is already fixed.

[0xRaReddy]

Seeing this issue now in docker build.
It looks like both docker images mcr.microsoft.com/dotnet/sdk:7.0 and mcr.microsoft.com/dotnet/nightly/sdk:7.0 have dotnet sdk 7.0.203