Background

I have installed the .NET framework on Arch GNU/Linux following the ArchWiki guide.

The main packages were:

• dotnet-runtime to run .NET managed applications
• dotnet-sdk to build apps with .NET

Furthermore, I added ~/.dotnet/tools to PATH so that I can use dotnet tools from shell. I've done so by adding

export PATH="$PATH:/home/MyUserName/.dotnet/tools"

to my ~/.zshenv file.

Problem

Everything worked fine, and I was able to build a few console apps. However, when I tried to build an ASP.NET Core Web App, I encountered some problems.

First, I created a new Web App by running:

dotnet new webapp -n MyAppsName --framework net6.0

When I try to build and run, I get the following error:

Building...
You must install or update .NET to run this application.

App: /home/MyUserName/RestOfThePath/MyAppsName/bin/Debug/net6.0/MyAppsName
Architecture: x64
Framework: 'Microsoft.AspNetCore.App', version '6.0.0' (x64)
.NET location: /usr/share/dotnet

No frameworks were found.

Learn about framework resolution:
https://aka.ms/dotnet/app-launch-failed

To install missing framework, download:
https://aka.ms/dotnet-core-applaunch?framework=Microsoft.AspNetCore.App&framework_version=6.0.0&arch=x64&rid=arch-x64

It seems that the framework (or the appropriate version) is missing. However, when I run dotnet --info, it does not seem that anything I need is missing. Below is the output of the previous command.

.NET SDK (reflecting any global.json):
 Version:   6.0.109
 Commit:    58a93139d8

Runtime Environment:
 OS Name:     arch
 OS Version:
 OS Platform: Linux
 RID:         arch-x64
 Base Path:   /usr/share/dotnet/sdk/6.0.109/

global.json file:
  Not found

Host:
  Version:      6.0.9
  Architecture: x64
  Commit:       163a63591c

.NET SDKs installed:
  6.0.109 [/usr/share/dotnet/sdk]

.NET runtimes installed:
  Microsoft.NETCore.App 6.0.9 [/usr/share/dotnet/shared/Microsoft.NETCore.App]

Download .NET:
  https://aka.ms/dotnet-download

Learn about .NET Runtimes and SDKs:
  https://aka.ms/dotnet/runtimes-sdk-info

What am I missing? Any help would be appreciated.

P.S. Here is the official Microsoft's article intended to help troubleshoot this particular issue. It did not provide any new insight.

CodePudding user response：

.Net (note, as of .Net 5 it's just called ".Net", not ".Net Core" or ".Net Framework") is distributed in three different packages.

The one you're missing is aspnet-runtime.

dotnet-sdk lets you compile source code. dotnet-runtime lets you run basic applications. aspnet-runtime comes with a lot of extra stuff specific for ASP.Net, so it's distributed separately.

NORMALLY (such as on Windows), when you install the .Net Sdk, it also installs the ASP.Net runtime. It seems that on Arch the SDK package doesn't depend on aspnet-runtime.

Once you install the aspnet-runtime and run dotnet --info again, you'll see under the ".NET runtimes installed" section an entry for "Microsoft.NETCore.App" (what dotnet-runtime provides) and Microsoft.AspNetCore.App (what aspnet-runtime provides).