.net – Maximum Filesize of LogFileAppender in Log4Net


I am using Log4net for a while now and it's an amazing logging framework, especially when hooked into Castle.Windsor. However…

I usually use the rolling file appender, but this has resulted in too many log files than I actually want, so instead, for my latest project, have used the basic LogFileAppender instead, but the problem is the log file keeps growing (seemingly forever).

How can I tell the appender to not go over a fixed size (and start removing old logs and appending the new ones to the file?

My current configuration looks like:

<appender name="LogFileAppender" type="log4net.Appender.FileAppender">
  <file value="E:\Logs\iWater\Schedule-Dispatch-API.log"/>
  <param name="AppendToFile" value="true"/>
  <maximumFileSize value="2048KB"/>
  <layout type="log4net.Layout.PatternLayout">
    <conversionPattern value="%-16date{dd MMM HH:mm:ss} %-7level %-25.35logger{1} %message%newline"/>

Its seems like the maximumFileSize attribute is not being respected. Any solutions?

Alternatively, how can I configure the rolling file appender to only create 1 file (ever)?

Best Answer

The FileAppender class does not have the MaxFileSize/MaximumFileSize properties. You only get those if you use a RollingFileAppender. Here's an example that will limit your file to a fixed maximum size, with no backups (set maxSizeRollBackups to 0). Note that when the file reaches its max size, it truncates (basically deletes all existing logging and starts over):

<appender name="RollingFileAppender" type="log4net.Appender.RollingFileAppender">
    <file value="log.txt" />
    <appendToFile value="true" />
    <rollingStyle value="Size" />
    <maxSizeRollBackups value="0" />
    <maximumFileSize value="10MB" />
    <staticLogFileName value="true" />
    <layout type="log4net.Layout.PatternLayout">
        <conversionPattern value="%date [%thread] %-5level %logger [%property{NDC}] - %message%newline" />