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log4net is not logging to log file or console (external log4net.config file)

I created a a file called log4net.config in my project and added the following configuration:
<?xml version="1.0" encoding="utf-8" ?>
<configuration>
<configSections>
<section name="log4net" type="log4net.Config.Log4NetConfigurationSectionHandler,log4net" />
</configSections>
<log4net>
<root>
<level value="ALL" />
<appender-ref ref="console" />
<appender-ref ref="RollingFileAppender" />
</root>
<appender name="console" type="log4net.Appender.ConsoleAppender">
<layout type="log4net.Layout.PatternLayout">
<conversionPattern value="%date %level %logger - %message%newline" />
</layout>
</appender>
<appender name="RollingFileAppender" type="log4net.Appender.RollingFileAppender">
<param name="File" value="${LOCALAPPDATA}\MyApp\LogFile.log" />
<param name="AppendToFile" value="true" />
<rollingStyle value="Size" />
<maxSizeRollBackups value="10" />
<maximumFileSize value="10MB" />
<staticLogFileName value="true" />
<layout type="log4net.Layout.PatternLayout">
<param name="ConversionPattern" value="%-5level [%d{yyyy-MM-dd hh:mm:ss}] [%thread] (Line:%line) %M: - %m%n" />
</layout>
</appender>
</log4net>
</configuration>
After that, I added the line below to my AssemblyInfo.cs file:
[assembly: log4net.Config.XmlConfigurator(ConfigFile = "log4net.config", Watch = true)]
In the application, I have the following static class:
public static class Logger
{
private static readonly ILog log = LogManager.GetLogger(System.Reflection.MethodBase.GetCurrentMethod().DeclaringType);
public static void LogInfo(string msg)
{
log.Info(msg);
}
public static void LogDebug(string msg)
{
log.Debug(msg);
}
public static void LogWarn(string msg, Exception e)
{
log.Warn(msg, e);
}
public static void LogError(string msg, Exception e)
{
log.Error(msg, e);
}
}
Then I'm trying to log somewhere in the application in another class using Logger.LogDebug("Error logger working.");
However, I can't see any log file being created or written to it. What am I doing wrong?
UPDATE:
I also added the following in my app.config file but I see nothing at all on my Output console...
<appSettings>
<add key="log4net.Internal.Debug" value="true"/>
</appSettings>

If you have the log4net configuration in a log4net logging configuration file, you do not have to add the configuration of the web.config (configuration tag and sections). Just add the log4net tags:
<log4net>
<root>
<level value="ALL" />
<appender-ref ref="console" />
<appender-ref ref="RollingFileAppender" />
</root>
<appender name="console" type="log4net.Appender.ConsoleAppender">
<layout type="log4net.Layout.PatternLayout">
<conversionPattern value="%date %level %logger - %message%newline" />
</layout>
</appender>
<appender name="RollingFileAppender" type="log4net.Appender.RollingFileAppender">
<param name="File" value="${LOCALAPPDATA}\MyApp\LogFile.log" />
<param name="AppendToFile" value="true" />
<rollingStyle value="Size" />
<maxSizeRollBackups value="10" />
<maximumFileSize value="10MB" />
<staticLogFileName value="true" />
<layout type="log4net.Layout.PatternLayout">
<param name="ConversionPattern" value="%-5level [%d{yyyy-MM-dd hh:mm:ss}] [%thread] (Line:%line) %M: - %m%n" />
</layout>
</appender>
</log4net>

I could not reproduce your mistake. Configure log4net in AssemblyInfo works fine. maybe the problem in configuration. let me show you another implementation
private static readonly ILog log = LogManager.GetLogger("myLogger");
private static string configFile = "log4net.config";
static Logger()
{
XmlConfigurator.Configure(new FileInfo(configFile));
}
log4net.config:
<log4net>
<logger name="myLogger">
<level value="ALL" />
<appender-ref ref="console" />
<appender-ref ref="RollingFileAppender" />
</logger>
<appender name="console" type="log4net.Appender.ConsoleAppender">
<layout type="log4net.Layout.PatternLayout">
<conversionPattern value="%date %level %logger - %message%newline" />
</layout>
</appender>
<appender name="RollingFileAppender" type="log4net.Appender.RollingFileAppender">
<param name="File" value="${LOCALAPPDATA}\MyApp\LogFile.log" />
<param name="AppendToFile" value="true" />
<rollingStyle value="Size" />
<maxSizeRollBackups value="10" />
<maximumFileSize value="10MB" />
<staticLogFileName value="true" />
<layout type="log4net.Layout.PatternLayout">
<param name="ConversionPattern" value="%-5level [%d{yyyy-MM-dd hh:mm:ss}] [%thread] (Line:%line) %M: - %m%n" />
</layout>
</appender>
</log4net>

Managed to find out the issue thanks to stuartd's comment. My problem was, my full solution had 2 projects. I had only configured one project (which is not the start-up project) for log4net.
My original log4net configuration did not have any mistake. I simply added log4net reference to my start up project and added log4net configuration to that project as well and it started logging.
Many thanks to everyone who tested my config.

How do I keep a log file per day in log4net? [duplicate]

This question already has answers here:
Having a log per day
(3 answers)
Closed 5 years ago.
I've inherited an application that I need to keep more than a single days of logs.
It is using log4net for it's logging, and I have the log4net.config file contents below:
<?xml version="1.0"?>
<log4net>
<appender name="Console" type="log4net.Appender.ConsoleAppender">
<layout type="log4net.Layout.PatternLayout">
<conversionPattern value="%date [%thread] %-5level %logger [%property{NDC}] - %message%newline" />
</layout>
</appender>
<appender name="RollingFileAppender" type="log4net.Appender.RollingFileAppender">
<file value="logs\connector.log" />
<appendToFile value="true" />
<rollingStyle value="Date" />
<datePattern value="yyyyMMdd" />
<maxSizeRollBackups value="10" />
<maximumFileSize value="5MB" />
<layout type="log4net.Layout.PatternLayout">
<conversionPattern value="%date [%thread] %-5level %logger [%property{NDC}] - %message%newline" />
</layout>
</appender>
<root>
<level value="INFO" />
<appender-ref ref="Console" />
<appender-ref ref="RollingFileAppender" />
</root>
</log4net>
The file in the log directory never has a date in it and is always called connector.log.
It's created date is from a long time ago, so I think it is simply emptying the file when it ticks over to a new day (and the timestamp of logs in that file prove that).
How would I change this so that it keeps a log file per day.

<appender name="SysAppender" type="log4net.Appender.RollingFileAppender,log4net">
<param name="File" value="App_Data/" />
<param name="AppendToFile" value="true" />
<param name="RollingStyle" value="Date" />
<param name="DatePattern" value=""Logs_"yyyyMMdd".htm"" />
<param name="StaticLogFileName" value="false" />
<layout type="log4net.Layout.PatternLayout">
<param name="ConversionPattern" value="<HR COLOR=red>%n异常时间：%d [%t] <BR>%n异常级别：%-5p <BR>%n异 常 类：%c [%x] <BR>%n%m <BR>%n <HR Size=1>" />
<!--<conversionPattern value="%newline %n记录时间：%date %newline %n 线程ID:[%thread] %n日志级别： %-5level %n跟踪描述：%message%newline %n"/>-->
</layout>
</appender>
needn't define log file's name

Load only one appender instead of all

I'm currently working on a console C# app and I have to log two type of data :
All steps of the app in general (AppLog)
All information that I get from a service (MachineLog)
MachineLog needs 2 propeties, but when I start the app I do not define them I have some work to do before. But I need to log from start whith AppLog so at le beginning I use :
log4net.Config.XmlConfigurator.Configure();
And it create me the C:\DNC\Suivi\Logs.txt but also C:\DNC\Suivi\(null)\(null)-logs.txt
Is there any way to only load/configure AppLog and later MachineLog ?
I tried to add parameters to Configure() and all failed.
My App.config is :
<?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="AppLog" />
</root>
<logger name="Machine" additivity="false">
<level value="ALL" />
<appender-ref ref="MachineLog" />
</logger>
<appender name="AppLog" type="log4net.Appender.RollingFileAppender">
<file value="C:\DNC\Suivi\Logs.txt" />
<appendToFile value="true" />
<rollingStyle value="Size" />
<maxSizeRollBackups value="10" />
<maximumFileSize value="10MB" />
<staticLogFileName value="true" />
<layout type="log4net.Layout.PatternLayout">
<conversionPattern value="%date [%thread] %-5level %logger [%property{NDC}] - %message%newline" />
</layout>
</appender>
<appender name="MachineLog" type="log4net.Appender.RollingFileAppender" >
<file type="log4net.Util.PatternString" value="C:\DNC\Suivi\%property{Machine}\%property{ID}-logs.txt" />
<appendToFile value="true" />
<rollingStyle value="Size" />
<maxSizeRollBackups value="10" />
<maximumFileSize value="10MB" />
<staticLogFileName value="true" />
<layout type="log4net.Layout.PatternLayout">
<param name="ConversionPattern" value="%date [%thread] %-5level %logger [%property{NDC}] - %message%newline" />
</layout>
</appender>
</log4net>
</configuration>

With your current configuration, you can't do it. As you have seen, log4net will create the log files when XmlConfigurator.Configure() is called.
In order to this, you will have to do at least some work programmatically, once you know where the file will be - it's quite easy to set the file name at runtime so you can have a placeholder file name in the config, then set the correct name at runtime when the values are known. This does mean that the empty placeholder file will exist - the only way around that would be to create the whole appender at runtime.

Emailing a log4net log as a System.Net.Mail.Attachment throws IOException (process locked)

I wanted to send the current log4net log as an email attachment using System.Net.Mail.Attachment but when I pass in the file path an IOException is thrown.
Attachment mailAttachment = new Attachment(logPath);
The process cannot access the file 'C:\Log\log4net.log' because it is being used by another process
The appender configuration looks like this:
<appender name="RootRollingLogFileAppender" type="log4net.Appender.RollingFileAppender">
<param name="File" value="C:\Log\log4net.log" />
<param name="AppendToFile" value="true" />
<param name="MaxSizeRollBackups" value="10" />
<param name="MaximumFileSize" value="10024KB" />
<param name="RollingStyle" value="Size" />
<param name="StaticLogFileName" value="true" />
<layout type="log4net.Layout.PatternLayout">
<param name="ConversionPattern" value="%date [%username|%thread] %-5level %logger: %message%newline" />
</layout>
</appender>
Is there any way to get around this? Can I copy out the log file or somehow release it from the locking process?

<appender name="FileAppender" type="log4net.Appender.FileAppender">
<file value="${TMP}\log-file.txt" />
<appendToFile value="true" />
<lockingModel type="log4net.Appender.FileAppender+MinimalLock" />
<layout type="log4net.Layout.PatternLayout">
<conversionPattern value="%date [%thread] %-5level %logger [%property{NDC}] - %message%newline" />
</layout>
</appender>
using <lockingModel type="log4net.Appender.FileAppender+MinimalLock" /> will tell log4net to only lock the file for a brief moment while it is doing the actual writing. There is a slight performance penalty, but allows you to do things such as add it as an attachment a lot easier.
Otherwise log4net will lock the file indefiniately while the process is running.

current date in app.config

Im trying to create a log file using log4net.
I have it create a log file. But i can't get the name of the log file to be the current date.
I have tried this:
<file value="log\\$date.txt"/>
But this just leans me with a file called "$date.txt" in the log folder.
I would like the file to be named "25-04-2012.txt"
Anyone know the little trick to make this work?

From the documentation, you should use a RollingFileAppender
This example show how to configure the RollingFileAppender to roll log
files on a date period. This example will roll the log file every
minute! To change the rolling period adjust the DatePattern value. For
example, a date pattern of "yyyyMMdd" will roll every day. See
System.Globalization.DateTimeFormatInfo for a list of available
patterns.
<appender name="RollingLogFileAppender" type="log4net.Appender.RollingFileAppender">
<file value="logfile" />
<appendToFile value="true" />
<rollingStyle value="Date" />
<datePattern value="yyyyMMdd-HHmm" />
<layout type="log4net.Layout.PatternLayout">
<conversionPattern value="%date [%thread] %-5level %logger [%property{NDC}] - %message%newline" />
</layout>
</appender>
Documentation (search for rollingFileappender)

<appender name="LogFileAppender" type="log4net.Appender.RollingFileAppender" >
<param name="File" value="C:\Akhila\logger\logger\bin\Debug\log-" />
<param name="AppendToFile" value="true" />
<rollingStyle value="Date" />
<datePattern value="yyyy-MM-dd" />
<staticLogFileName value="false" />
<layout type="log4net.Layout.PatternLayout">
<param name="ConversionPattern" value="%-5p%d{yyyy-MM-dd hh:mm:ss} – %m%n" />
</layout>
</appender>