log4net doesn't create log file when deployed on IIS7

Question

Good morning everybody,

I have a log4net issue that didn't exist when I was developing on my local machine, but once I deployed the application to a server, log4net stopped working.

This is the server configuration : -Windows XP SP3 -IIS 7 -framework .Net v4

This is the log4net configuration in the web.config of the website:

<configuration>
      <log4net>
        <root>
          <level value="DEBUG" />
          <appender-ref ref="LogFileAppender" />
        </root>
        <appender name="LogFileAppender" type="log4net.Appender.RollingFileAppender">
          <param name="File" value="log.txt" />
          <param name="AppendToFile" value="true" />
          <rollingStyle value="Size" />
          <maxSizeRollBackups value="10" />
          <maximumFileSize value="30MB" />
          <staticLogFileName value="false" />
          <layout type="log4net.Layout.PatternLayout">
            <param name="ConversionPattern" value="%-5p%d{yyyy-MM-dd hh:mm:ss} – %m%n" />
          </layout>
        </appender>
      </log4net>
    </configuration>

I also have a class library and this is its App.config file:

<?xml version="1.0" encoding="utf-8" ?>
<configuration>
  <configSections>
    <section name="log4net" type="log4net.Config.Log4NetConfigurationSectionHandler,Log4net"/>
  </configSections>
  <log4net>
    <root>
      <level value="DEBUG" />
      <appender-ref ref="LogFileAppender" />
    </root>
    <appender name="LogFileAppender" type="log4net.Appender.RollingFileAppender" >
      <param name="File" value="log.txt" />
      <param name="AppendToFile" value="true" />
      <rollingStyle value="Size" />
      <maxSizeRollBackups value="10" />
      <maximumFileSize value="30MB" />
      <staticLogFileName value="true" />
      <layout type="log4net.Layout.PatternLayout">
        <param name="ConversionPattern" value="%-5p%d{yyyy-MM-dd hh:mm:ss} – %m%n" />
      </layout>
    </appender>
  </log4net>
</configuration>

This is how I call the log function on every class:

private static readonly ILog log = LogManager.GetLogger(typeof(AppDomain));

...and this is how i call it :

log.Error("\n\t=>" + ex.GetBaseException().Message + "\n\r" + " @ " + Environment.StackTrace);

Answer 1

I had the same problem myself and it turned out that I had forgot to set the "Build Action" for the configuration file. Therefore the log4net.config file was not deployed, and this is of course needed to make the application write the log file.

Answer 2

It could be that you do not have permissions to write to the file 'log.txt'.

I don't know what the current directory would be but it's unlikely to be somewhere IIS can write to.

You need to create a folder somewhere and grant access for IIS to write to it, I understand you need to grant access to the IIS_IUSRS group and then specify the absolute path to that file. e.g.

<param name="File" value="D:\Logs\log.txt" />

..using the path to your preferred location.