The ASP.NET Core Module generates a dynamic port to assign to the back-end process. CreateDefaultBuilder calls the UseIISIntegration method, which picks up the dynamic port and configures Kestrel to listen on http://localhost:500For more Details go through the linkhttps://docs.microsoft.com/en-us/aspnet/core/host-and-deploy/iis/?view=aspnetcore-2.1
This json file holds project specific settings associated with each debug profile, Visual Studio is configured to use to launch the application, including any environment variables that should be used. You can define framework for your project for compilation and debugging for specific profiles. This file is placed in Properties folder.
This tells ASP.NET that IIS will be working as a reverse proxy in front of Kestrel. As if you expose your application to the Internet, you must use IIS, Nginx, or Apache as a reverse proxy server. When you wish to deploy your ASP.NET Core application on windows, you need to tell ASP.NET Core Host to use IIS integration.UseKestrel and UseIISIntegration must be used in conjunction as UseKestrel creates the web server and hosts the code. UseIISIntegration specifies IIS as the reverse proxy server.
var host = new WebHostBuilder() .UseKestrel() .UseContentRoot(Directory.GetCurrentDirectory()) .UseIISIntegration() .UseStartup() .Build();
https://stackoverflow.com/questions/55673395/mvc-core-what-is-the-difference-between-useiis-and-useiisintegration
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