如何将外部域绑定到 .NET Core 3.1 Kestrel 自托管应用程序？

Question

I have a simple .NET Core 3.1 self-hosted Kestrel application. After publishing to my server, it runs correctly at http://localhost:5000 .

I want to access this application via a remote browser, so I changed the Program.cs as below:

public class Program
{
    public static void Main(string[] args)
    {
        CreateHostBuilder(args).Build().Run();
    }

    public static IHostBuilder CreateHostBuilder(string[] args) =>
    {
        Host.CreateDefaultBuilder(args).ConfigureWebHostDefaults(webBuilder =>
        {
            webBuilder.ConfigureKestrel(so =>
            {
                so.Listen(IPAddress.Any, 5000); //==> This is OK
            });
            webBuilder.UseStartup<Startup>();
        });
    }   
}

Now the application is reachable from any remote browser via http://IP:port address. Instead of using IP:Port, however, I want to bind a domain URL (for example www.XXXX.com ) to my application.

I use Cloudflare as my DNS and proxy server. Keep in mind that Cloudflare does not support port forwarding. Also, the Portzilla App in Cloudflare had no use for me.

What I have done so far is I've added a new IP (let's say 112.250.22.33 ) to the server, and tried to configure the application to listen on port 80 of this specific IP address:

webBuilder.ConfigureKestrel(so =>
{
    so.Listen(IPAddress.Parse("112.250.22.33"), 80); //==> NOT OK
});

With this configuration, however, the application does not run at all—even if I run it in Run as administrator mode. Instead, it returns with this error:

Microsoft.AspNetCore.Server.Kestrel[0] Unable to start Kestrel. System.Net.Sockets.SocketException (10013): An attempt was made to access a socket in a way forbidden by its access permissions.

Any help will be appreciated.

Answer 1

I am not sure, but looks like 80 port is holding by IIS. I disabled DefaultWebSite and could bind domain name to local Kestrel run.