log4net , Possible to set up Log4net Notification When it Crashes?

Possible to set up Log4net Notification When it Crashes?


Tag: log4net

Log4net fails silently by design. Good. I don't want it taking down my app.

Is there a way to set up a notification when Log4net crashes and stops logging?

Is there some kind of event handler that I can hook into which will tell me that Log4net has gone silent?

I want to know when this happens so I can recycle the app pool as soon as possible.



If I'm understanding you correctly, you would like log4net to signal you when an appender fails. If we look at the logging code for the Logger implementation we see that the only point that takes into account the appenders failing is the internal logging mechanism:

// log4net.Repository.Hierarchy.Logger
public virtual void Log(Type callerStackBoundaryDeclaringType, Level level, object message, Exception exception)
        if (this.IsEnabledFor(level))
            this.ForcedLog((callerStackBoundaryDeclaringType != null) ? callerStackBoundaryDeclaringType : Logger.ThisDeclaringType, level, message, exception);
    catch (Exception exception2)
        LogLog.Error("Log: Exception while logging", exception2);
        LogLog.Error("Log: Exception while logging");

Of course this occurs only if the appender throws an exception. The LogLog component then forwards the message to the Console and Trace components:

// log4net.Util.LogLog
private static void EmitErrorLine(string message)

So, by listening messages coming from the trace you can get an idea of what happens in your appenders. To turn this into an event you can add a trace listener that triggers in some specific cases: you can take a look at what is in this answer regarding custom trace listeners in order to trigger an event from one.


AssemblyInfo.vb change Log4NetAssembly1.exe.log4net path to user's local folder

My vb.net project used for different users, I am lost in how to set the Log4NetAssembly1.exe.log4net file path to user's local folder in AssemblyInfo.vb. The Log4NetAssembly1.exe.log4net file is located in C:\Users\UserName\AppData\Local\Temp\DeskApp\DeskApp\Log4NetAssembly1.exe.log4net for each user. I have tried to use the following way but it not work: <Assembly: AssemblyTitle("DeskApp")> <Assembly: AssemblyDescription("")>...

What is the disadvantage of manually registering Log4Net Logger instance to ILog in Autofac?

Autofac has log4net Integration Module called LoggingModule. However, I register Logger to ILog manually without using LoggingModule, and it seems working fine. ILog log = LogManager.GetLogger("Logger"); builder.RegisterInstance(log).As<ILog>().SingleInstance(); My question is - what is the disadvantage/side effect of using above approach instead of using LoggingModule. web.config <?xml version="1.0" encoding="utf-8"?> <configuration> <configSections>...

log to redshift using log4net's adonetappender

I'm trying to log to my redshift server using log4net's builtin adonetappender. When the timestamp field is removed the log will successfully be saved. However, the format of the timestamp seems to be causing it to fail. I have tried many different formats that match what redshift claims to support....

Log4Net how to use both the ErrorFormat and the Error at the same time

In log4net there are 2 very nice functions: Log.Error("Message", myException); and Log.ErrorFormat("Message {0}", CustomerId); The produce log records in the output log file very nicely. The exception one is nice because it prints a stack trace and all the exception details nicely, and the Format one is nice because it...

Logging / Tracking CRUD operations in MVC application

I want to save all of the CRUD operations with the user's detail to the database and then monitor these info according to the following approach below. In my opinion, the second approach seems better so that it can be managed from one specific table and can also be used...

Raygun with log4net not logging

I have a simple console app. Downloaded log4net nuget package as well as log4net raygun nuget package: https://www.nuget.org/packages/log4net.Raygun/. I've set up my app to log exceptions and info messages and I do get those in my log file, but NOT in raygun dashboard, Nor do I get emails from raygun.io....

Possible to set up Log4net Notification When it Crashes?

Log4net fails silently by design. Good. I don't want it taking down my app. Is there a way to set up a notification when Log4net crashes and stops logging? Is there some kind of event handler that I can hook into which will tell me that Log4net has gone silent?...

Two loggers writing to same file

I configured two loggers and want them to simultaneously log to Event Log and text file, but they both logging to text. Here is my configuration file: <log4net> <appender name="RollingFile" type="log4net.Appender.RollingFileAppender"> <file value="NavRiskFileImportError.log" /> <appendToFile value="true" /> <maximumFileSize value="100KB" /> <maxSizeRollBackups value="2" /> <datePattern value="yyyyMMdd" /> <staticLogFileName value="true" /> <layout...

not able to log nihibernate sql (info,debug,error ) messages

I want to log debug ,info and error message of Nhibernate.SQL. I am not able to log all the messages. Can i use config as below? <logger name="NHibernate.SQL"> <level value="DEBUG" /> </logger> <logger name="NHibernate.SQL"> <level value="INFO" /> </logger> <logger name="NHibernate.SQL"> <level value="ERROR" /> </logger> or do I need to use...

Adding date in filename of RollingFileAppender files

Hi I am now using log4net for some time. This is my Logger: public static class LoggerSetup { private static RollingFileAppender _roller; private static PatternLayout _patternLayout; static LoggerSetup() { // root config Hierarchy hierarchy = (Hierarchy)LogManager.GetRepository(); hierarchy.Root.Level = Level.Debug; hierarchy.Configured = true; // prepare appender _roller = new RollingFileAppender(); _patternLayout...

log4net context for capturing browser capabilities

I want to use log4net to log browser capabilities in a custom property. What is the best context to be used here? log4net.GlobalContext log4net.ThreadContext log4net.ThreadLogicalContext log4net.Core.LoggingEvent ...

How do I retrieve my custom logger by class name and output the actual class name from multiple places?

The following syntax seem to be accepted for retrieveing a logger from log4net: var log = LogManager.GetLogger(System.Reflection.MethodBase.GetCurrentMethod().DeclaringType); because it avoids having to hard-code the specific type of the class logging: var log = LogManager.GetLogger(typeof(MyClass)); I do understand that point, and also that you can create your own logger and use...

Log4net - modify logging levels for individual logger and appender combinations

I have two appenders, one (InfoAppender) with a levelMin info filter and one (DebugAppender) without filter. This works great. I can also set minimum logging levels for individual loggers using the element. But now I want to have most loggers logging info (and above) to InfoAppender and debug (and above)...

Could not load file or assembly 'log4net, Version=, Culture=neutral, PublicKeyToken=1b44e1d426115821'

I have added Log4Net in my project using NuGet Package Manager and it is showing Version 2.3 installed on my system. Here is my config entry: <configSections> <section name="dataConfiguration" type="Microsoft.Practices.EnterpriseLibrary.Data.Configuration.DatabaseSettings, Microsoft.Practices.EnterpriseLibrary.Data, Version=, Culture=neutral, PublicKeyToken=31bf3856ad364e35"/> <section name="log4net" type="log4net.Config.Log4NetConfigurationSectionHandler, log4net" /> </configSections> and then reference to...

Can I redirect output from a C DLL into my c# log4net output

I have a C# application which in turn loads a C or C++ dll (which in turn loads other C/C++ dlls). Within the C# application I use a log4net logger to capture all the output into a series of log files. My application runs as a windows service so there...

log4net %property does not work

I have a small test project with the following code: class Program { static void Main(string[] args) { log4net.GlobalContext.Properties["logFileName"] = "log.txt"; log4net.Config.XmlConfigurator.Configure(new System.IO.FileInfo("log4net.xml")); log4net.ILog logger = log4net.LogManager.GetLogger("Tests"); logger.Debug("Test message"); } } My log4net.xml config file has the following content: <?xml version="1.0" encoding="utf-8" ?> <log4net> <appender name="RollingFileAppender" type="log4net.Appender.RollingFileAppender">...

Log4net not logging exception

I have log4net successfully setup for my C# application. Everything works fine, except when I do this: catch (Exception ex) { if (log.IsErrorEnabled) log.Error("test", ex); } All I get is the message "test", I do not get the exception at all. Then, when I do this: catch (Exception ex) {...

c# static object reference

I have a class like so public class FileLogger { public FileLogger(string typeOfLog) { //implementation } public void LogError(string err) { //implementation } public void LogMessage(string err) { //implementation } } Since this is a logging class for an application to log its output to a file, one would have...

Changing log level without restarting application

It is possible to change log4net logging level without restart ASP.NET application. Some possible ways to configure log4net configuration are: ASP.NET web config file. adding separate config file and referring config file inside AssemblyInfo.cs file: [assembly:log4net.Config.XmlConfigurator(ConfigFile="Log4Net.config",Watch=true)] Changing the configuration in a web.config file will restart the application. If I don't...

Using the assembly version in log4net FileAppender file name

I have a log4net logfile appender defined as follows. It works fine. I'd like to put the assembly version of the exe as the file name to better distinguish what version is in play. So, in the example below, I'd like to have ClientAppLog_v1.2.3.4.txt, if the assembly version of my...

RuntimeBinderException when trying to use dynamic type

im trying to implement log4net in my current log pattern i have setup but i ran into some problem when trying to convert my enum LogLevel to log4net's Level class. the problem lays in the ChangeLogLevelTo method: Exception: An exception of type 'Microsoft.CSharp.RuntimeBinder.RuntimeBinderException' occurred in System.Core.dll but was not handled...

Log4net rolling filenames [duplicate]

This question already has an answer here: log4net rolling file appender file name format when maximumFileSize reached 1 answer I'm using log4net in a C# application <log4net> <appender name="RollingFileAppender" type="log4net.Appender.RollingFileAppender"> <file value="..\logs\Program.log.xml" /> <appendToFile value="true" /> <rollingStyle value="Size" /> <maxSizeRollBackups value="10" /> <maximumFileSize value="10000KB" /> <staticLogFileName value="true" /> <layout...

log4net logging UnhandledException exceptions from different projects

I have several projects in my solution, most of which are windows services. I have log4net configured for each (generating a separate log file for each), as well as Raygun appender for log4net. I would like to catch UnhandledException for each of these projects and have info of where they...

Using log4net to log unhandled errors when using OWIN

Can you point me to some log4net tutorial or samples that logs all unhandled exceptions occurring on my MVC Web Api when using OWIN? I have a Startup class that configures Castle Windsor and OAuth and I'm not sure how application errors are handled for OWIN enabled applications. I have...

Log4Net with Asp.NET MVC, entity framework and dependency injection using NInject [closed]

Just started with Log4Net, read the tutorial and got up with a simple console application. But I am wondering how to get started with MVC and entity framework code first with dependency Injection using NInject. Can some one please give some pointers?

Programatically configuring log4net to write to separate log files

I am following this example to programatically configure log4net. However since I want to log information separately and errors separately I modified the setup method as below public static void Setup() { Hierarchy hierarchy = (Hierarchy)LogManager.GetRepository(); PatternLayout patternLayout = new PatternLayout(); patternLayout.ConversionPattern = "%date [%thread] %-5level %logger - %message%newline"; patternLayout.ActivateOptions();...

Log4Net error : “Failed to find configuration section log4net” AdoNetAppender

I made a new Projekt only for testing. I am trying to use LOG4Net to write into my DB. But I am still getting the Same Error. Below you can see my files and my data. I can not tell you the names of my DB and table but they...

Making a log4net appender conditionally choose between properties for a particular field

I have a common logging project that uses log4net to record logging events. Since it's a common project, it's configured in a non-standard way: almost everything is set via C# code. Now, I have an AdoNet appender configured in this manner, which includes logging the method that triggered the log...

Check whether log4net XmlConfigurator succeeded

How to check whether a call to log4net's XmlConfigurator.Configure succeeded? I want to make a web service call if the logging configuration could not be loaded properly (i.e. file not existent, file not well-formed, etc.)

How to log asynchronously with log4net in an ASP.NET MVC Web Application without using up all available threads?

Is AsyncForwardingAppender of the Log4Net.Async package safe to use in an ASP.NET MVC Web Application? I'm worried that it will clog up the available threads. It comes down to me wanting to make a call to an async method to send the logs to an HTTP API. I could use...

Log4Net AdoNetAppender- truncate table / delete old records / limit DB size

What would be a simple way to effectively limit the size of the table Log4Net logs in to? Something like deleting old records, or deleting when the total number of records reaches a predefined limit, or when the table (or DB) size reaches a size limit (edit) since we have...

What's wrong with my log4net config file

I have a config file with two appenders, one file appender and one database appender. I want to log everything to the file appender, and only log exceptions to the database appender. When setting up both appenders in the section it logs fine but all log events are sent to...

No appenders instantiated when running locally

I have a web application which uses log4net. My web application is deployed to Azure, and works there perfectly. However when I run it locally through VS2013 (update 4), log4net doesn't instantiate the AdoNetAppender. I checked for exception by breaking on all thrown exceptions, nothing was thrown, I activated the...

filter to not log logging entries of particular class

I have a adonet appender and rolling file appender configure for my application. What i want is a filter on my adonetappender via which i can omit logging on particular class. That class has multiple level of devugging which I needed for my file appender. so i can't change the...

Transitioning from log4net to log4j 2

I am working on a project in java which uses log4j2 and want to setup logging the same as I had in older project in .NET using log4net. There are some things I cant figure out, how to do in the log4j2. How can I force log4j2 appender to put...

Specific log4net-logfile for PayPal

Is it possible to specify the logfile in the App.config? I found these parameters in .NET: https://github.com/paypal/sdk-core-dotnet/wiki/SDK-Configuration-Parameters In PHP it seems to be possible (Logging): https://github.com/paypal/sdk-core-php/wiki/Configuring-the-SDK Now, the informations will be saved in the first of many stated logfiles....

AdoNetAppender get connectionstring value from another file

I have multiple web services that currently logs their info\error messages using log4net into file. I want the logging now to be done in DB. I've read about AdoNetAppender and I can see that given some parameters such as command text and connection string it can be easily done. BUT...

Differences between the usage of log4net, ETW & TraceLogging

I have used Debug.WriteLine to debug an existing legacy application to find the program flow. Now I'm studying an event (message) based application which contains multiple services which react on events. It uses many cloud (like Azure) resources. I'm trying to understand the different logging system ETW (Event Tracing For...

log4net inserting (null) into custom column

Added a custom column as suggested here. Things are working fine when ever I log something into this column using the code line log4net.GlobalContext.Properties["CustomColumn"] = "Custom value"; But if I pass null instead as below log4net.GlobalContext.Properties["CustomColumn"] = null; this is logged as (null)(a string null included in brakets). This also...

ILogger.Log method declaringType parameter

When I wanted to use the different logging levels available with log4net, I found out that I needed to use the method ILogger.Log, which looks like this: void Log(Type callerStackBoundaryDeclaringType, Level level, object message, Exception exception); We can get an ILogger reference from our usual ILog reference to call this...

log4net delete file at runtime is it possible c#

Is it possible to delete a log at runtime? What I would like to do before the application starts is deleting all logs; if that is not possible I would like to clear all logs at runtime. Any suggestion/code snippet?...

log4net cross platform XML config

I have a requirement to store my log files in a Logs sub folder. Normally you would do this my modifying the FileAppender in you App.config as follows: <file type="log4net.Util.PatternString" value="Logs\MyLog.log" /> However this is not cross platform because if you run this on linux it will create a file...

working with log4net package

I recently added the log4net package in to my WCF web application. now I have few questions I: I added the log4net package through the VS 2013 package install and it added whole package. My guess is that log4net is just the dll and I can add it to my...

Use log4net with separate config file

my AssemblyInfo.cs: [assembly: log4net.Config.XmlConfigurator(ConfigFile = "Log4Net.config", Watch = true)] i change the structure just like you said (i just change the <file value="..\Logs\\CurrentLog" /> to <file value="D:\Log\Log.txt" />): <?xml version="1.0" encoding="UTF-8"?> <log4net> <root> <level value="ALL" /> <appender-ref ref="RollingFileAppender"/> </root> <appender name="RollingLogFileAppender" type="log4net.Appender.RollingFileAppender"> <file value="D:\Log\Log.txt"...

How to intercept and replace Quartz.NET's default logging at runtime?

In order to eliminate human error and avoid the tedium of maintaining who-knows-how-many App.config files, I've decided to set all of my Quartz.NET jobs' Log4Net configurations at runtime, completely in code. No App.config files allowed. I've been successful in getting a standalone console app to do this, as demonstrated here....

How to use Log4net to log in File in Windows Application

I'm trying to use Log4net for the first time in my WinForm application, before that I thought to see if it works in my Console application which didn't even produce any log file. I have referred other posts as well to achieve logging but to no avail. To get NHibernate...

403 Forbidden with Log4Net and MVC5

So I followed this tutorial to add logging to my project. Locally everything works fine, but when I deploy it to my staging environment and try to even visit the root page of the site I get a 403.14 Forbidden error saying that I need to enable Directory Browsing. I...

log4net not working using log4net appender azure in MVC applcation

same log4net appender azure nuget code working fine for console app, but not working in MVC application. I'm using this nuget log4net.Appender.Azure 1.1.1 already added log4net.Config.XmlConfigurator.Configure(); in Global.asax web.config <log4net> <!-- Azure Table Appender, uncomment, set proper QueueName and AWS credentials (appSettings) to try it out --> <appender name="AzureAppender1" type="log4net.Appender.AzureTableAppender,...

How to configure Log4Net to Delete logs by date

<appender name="FileAppender" type="log4net.Appender.RollingFileAppender"> <file value="logs\" /> <appendToFile value="true" /> <rollingStyle value="Date" /> <maxSizeRollBackups value="30" /> <datePattern value="yyyy-MM-dd'.txt'" /> <staticLogFileName value="false" /> <layout type="log4net.Layout.PatternLayout"> <conversionPattern value="%d{yyyy-MM-dd HH:mm} %-5level %message%newline%exception" /> </layout> <lockingModel...

log4net - how to filter out exceptions which contain a specified text?

I use log4net to log exceptions, and it generally works fine. But I would like to be able to filter out exceptions which contain a specific text string. I found this example of implementing a filter, but it does the opposite of what I want; it only includes messages with...