Log Stream of App Service stopped working

Question

I used the Log Stream feature quite often and it worked very well. But some time ago it stopped working at all.

I turn on "Application Logging (File System)" and set the Level to "Information" as always, but I don't see any of my log messages in the stream.

It is an ASP.net Core App.

No new logfile is created in D:\home\LogFiles\Application

It seems like the content of D:\home\LogFiles\SiteExtensions\DaaS\some-guid.txt is written to the log stream instead...??

Answer 1

I fixed the problem by adding the AzureWebAppDiagnostics Logging provider.
A few months ago this was not needed, so it seems the defaults have been changed at some time.

public static IHostBuilder CreateHostBuilder(string[] args) =>  
    Host.CreateDefaultBuilder(args)  
        .ConfigureLogging(logging =>  
        {  
            logging.AddAzureWebAppDiagnostics();     
        })  
        .ConfigureWebHostDefaults(webBuilder =>  
        {  
            webBuilder.UseStartup();  
        });  

See https://learn.microsoft.com/en-us/aspnet/core/fundamentals/logging/?view=aspnetcore-3.1

Answer 2

@Alexander Großauer Thanks for the reply! To add to this the Filesystem option is for temporary debugging purposes and turns itself off in 12 hours. So, could you try changing it to blob option which is for long-term logging and require blob storage container. Let me know how it goes.

Reference: https://learn.microsoft.com/en-us/azure/app-service/troubleshoot-diagnostic-logs#enable-application-logging-windows