Using Kestrel with .NET 7: Why can't I access ASP.NET Core app from another computer on the same network without IIS.

Question

Greetings everyone!

Using .NET 7, I created a simple ASP NET CORE app.
I am attempting to use only Kestrel without IIS to run this app. in appsettings.json:

{
  "Kestrel": {
    "Endpoints": {
      "Http": {
        "Url": "http://localhost:5000"
      },
      "Https": {
        "Url": "https://localhost:5001"
      }
    }
  }
}

I have tried every other configuration imaginable but nothing works.
In code, I attempted to configure Kestrel but nothing works.

Firewall turned off and the app works on the same machine but not the other computers on the same network.

Answer 1

if the apps works on the local machine, then it is configured correctly. to access from another machine, the firewall needs to be open on both machine. if you opened on the server, then its probably the client firewall.

note: 5000 and 5001 are not well know ports (0 to1023), nor are they in the dynamic range (49152 to 65535) that is typically open by default.

Answer 2

Hi @Orion-8602, Thanks for your patience. I took the test today and now I will share my results. We should use

builder.WebHost.UseUrls("http://0.0.0.0:5000"); 

Instead of builder.WebHost.UseUrls("http://*:5000"); ,then we can solve this problem. Here is my test code, I use 5031 port, when I double click .exe , file, then we can find the application start with 5031 port.

Summary

1. This kind of format with * , like [http://*:5000], used for launchSettings.json file.
2. No need to run netsh http add urlacl command, you can refer the document and delete it

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Best regards,

Jason Pan