title: Serilog `rollOnFileSizeLimit` doesn't work with configuration file
body: <p>When configure <code>Serilog</code> by configuration file(with nuget package <code>Serilog.Settings.Configuration</code>), it doesn't create rolling log file when size limit is reached.</p>
  
  <p>As suggested in <a href="https://stackoverflow.com/questions/39821560/serilog-rollingfile-sink-does-not-roll-files-based-on-date-and-size">this question</a> and <a href="https://github.com/serilog/serilog-settings-configuration/issues/184#issue-451936680" rel="noreferrer">this issue</a>, I'm using <code>Serlog.Sinks.File</code> (version 4.0.0), but rolling file is not created.</p>
  
  <p>This is my serilog config file <code>appsettings.json</code>:</p>
  
  <pre><code>{
    "Serilog": {
      "Using": [
        "Serilog.Sinks.File",
        "Serilog.Sinks.Console"
      ],
      "MinimumLevel": {
        "Default": "Debug",
        "Override": {
          "Microsoft": "Warning",
          "System": "Warning"
        }
      },
      "WriteTo": [
        {
          "Name": "File",
          "Args": {
            "path": "%LogPath%\\Logs\\log.txt",
            "rollOnFileSizeLimit ": true,
            "retainedFileCountLimit ": 20,
            "rollingInterval": "Day",
            "fileSizeLimitBytes": 10000
          }
        },
        {
          "Name": "Console"
        }
      ],
      "Enrich": [ "FromLogContext", "WithMachineName" ],
      "Destructure": [
      ],
      "Properties": {
      }
    }
  }
  </code></pre>
  
  <p>This is the code I tell <code>Serilog</code> to read from the configuration:</p>
  
  <pre class="lang-cs prettyprint-override"><code>//previous code ommited... 
  .ConfigureAppConfiguration((hostContext, configApp) =&gt;
                  {
                      Environment.SetEnvironmentVariable("LogPath", AppDomain.CurrentDomain.BaseDirectory);
                      configApp.AddJsonFile("appsettings.json", optional: false);
  
                      configApp.AddEnvironmentVariables();
                      configApp.AddCommandLine(args);
                  })
                  .UseSerilog((hostingContext, loggerConfiguration) =&gt;
                  {
                      loggerConfiguration
                          .ReadFrom.Configuration(hostingContext.Configuration);
                           .WriteTo.Console();
                  })
  </code></pre>
  
  <p>When file size reaches 10KB, it stops growing, and no new log file is created.
  BTW, rolling by day is still working.</p>
  
  <p>I also verified by configuring <code>Serilog</code> by code, and it works, so I think it's not related to the sink...</p>
  
  <p>This is the code which works</p>
  
  <pre class="lang-cs prettyprint-override"><code> .UseSerilog((hostingContext, loggerConfiguration) =&gt;
                  {
                      loggerConfiguration.MinimumLevel.Debug()
                              .MinimumLevel.Override("Microsoft", LogEventLevel.Information)
                              .Enrich.FromLogContext()
                              .WriteTo.File(path: Path.Combine(Environment.CurrentDirectory, "Logs", "log.txt"),
                                  rollOnFileSizeLimit: true,
                                  retainedFileCountLimit: 20,
                                  rollingInterval: RollingInterval.Day,
                                  fileSizeLimitBytes: 10000
                                  )
                              .WriteTo.Console();
                  })
  </code></pre>
  
  <p>So how could I make Serilog create rolling file when file size is reached by configuration file?</p>