Questions tagged [log4net]

The Apache log4net library is a tool to help the programmer output log statements to a variety of output targets. log4net is a port of the excellent Apache log4j™ framework to the Microsoft® .NET runtime. We have kept the framework similar in spirit to the original log4j while taking advantage of new features in the .NET runtime.

Apache log4net is a tool to help the programmer output log statements to a variety of output targets. In case of problems with an application, it is helpful to enable logging so that the problem can be located. With log4net it is possible to enable logging at runtime without modifying the application binary. The log4net package is designed so that log statements can remain in shipped code without incurring a high performance cost. It follows that the speed of logging (or rather not logging) is crucial.

At the same time, log output can be so voluminous that it quickly becomes overwhelming. One of the distinctive features of log4net is the notion of hierarchical loggers. Using these loggers it is possible to selectively control which log statements are output at arbitrary granularity.

log4net is designed with two distinct goals in mind: speed and flexibility.

Features:

  • Support for multiple frameworks
  • Output to multiple logging targets
  • Hierarchical logging architecture
  • XML Configuration
  • Dynamic Configuration
  • Logging Context
  • Proven architecture
  • Modular and extensible design
  • High performance with flexibility

Support for multiple frameworks:

log4net runs on all ECMA CLI 1.0 compatible runtimes. log4net has specific builds for the following frameworks:

  • Microsoft® .NET Framework 1.0
  • Microsoft .NET Framework 1.1
  • Microsoft .NET Framework 2.0
  • Microsoft .NET Framework 3.5
  • Microsoft .NET Framework 4.0
  • Microsoft .NET Framework 3.5 Client Profile
  • Microsoft .NET Framework 4.0 Client Profile
  • Microsoft .NET Compact Framework 1.0*
  • Microsoft .NET Compact Framework 2.0
  • Mono 1.0
  • Mono 2.0
  • Microsoft Shared Source CLI 1.0*
  • CLI 1.0 Compatible
  • Microsoft .NET Core 1.0 providing .NET Standard 1.3

The "Client Profile" builds are stripped down versions of the "normal" builds that don't contain any ASP.NET releated code - which for example means the %aspnet-* patterns and the AspNetTraceAppender are not available.

* Not supported by the binary release but can be built from the source release.

Official Website: http://logging.apache.org/log4net/

Useful Links:

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Disable NHibernate logging

I have an empty app.config file, but I still get NHibernate debug logs NHibernate: SELECT this_.LogID as LogID71_0_, this_.Level as Level71_0_, this_.Message as Message71_0_, this_.EventTime as EventTime71_0_, this_.Component as ... I tried adding…
ripper234
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Unrecognized configuration section log4net

I have this code in web.config:
Shreyas Achar
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log4net one file per run

I need my application to create a log file each time it runs. My preferred format would be App.log.yyyy-MM-dd_HH-mm-ss. If that's not possible, I'd settle for App.log.yyyy-MM-dd.counter This is my current appender configuration:
Diego Mijelshon
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Tracing versus Logging and how does log4net fit in?

I am wondering about what the difference between logging and tracing is. Is the difference basically that tracing is more detailed log giving developers a tool to debug applications at runtime? I have been experimenting with log4net and doing…
Xerx
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How do you log the machine name via log4net?

I am using Log4Net with the AdoNetAppender to log messages from a simple systray application into a SQL Server 2005 database. I want to log the machine name along with the log message because this application will be running on multiple machines and…
Stephen Tolton
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List of Log4net Conversion Patterns

Is there a comprehensive list of all the conversion patterns available for log4net? I can't even find them in the source code. All I have found is this; shouldn't there be more patterns? For example, how would I get the name of the hosting…
kay.one
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Can you pull the connectionString for a log4net AdoNetAppender from elsewhere in a web.config file?

I already have a db connection string in my web.config file. I scanned the log4net docs, but can't seem to find a way to use it within the log4net section of my web.config file. Is is possible to do something like this?
MrSharps
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MoveNext instead of actual method/task name

Using log4net declared as: private readonly ILog log = LogManager.GetLogger(MethodBase.GetCurrentMethod().DeclaringType()); In an async method or task, like this one: public async void CheckSomething() { log.Info(null); …
user1307346
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Log4net Not Creating Log File

I'm getting an error on a program that has log4net configured, but no log file is being created. I'm certain the logging is set up in the program because other users have created log files from the same, using an identical config file to what I'm…
That One Guy
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Configure log4net to send errors to different appenders based on level

I want to send Info Level & above to the XML appender and Error/Fatal Level to the EventLog appender. I gather that I need to modify the root element of the config but I'm struggling with the syntax. What is the configuration syntax to direct logs…
grenade
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How to fix "No way to resolve conflict between" error?

Recently added log4net.dll to our data object. Our data object builds perfectly but when you try to build anything that references our data object you get the following error: No way to resolve conflict between "log4net, Version=1.2.10.0,…
coding4fun
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When should I use Tracing vs Logger.NET, Enterprise Library, log4net or Ukadc.Diagnostics?

How do I choose between standard tracing, Logger.NET, Enterprise Library, log4net or Ukadc.Diagnostics? Is there a situation where one is more appropriate than the other? ... what would that be? (ASP.NET, console app, Azure Cloud, SOHO,…
makerofthings7
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Having a log per day

Currently my application is using log4net to log errors, the web.config for this is as followed:
swade1987
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Writing logs to file

I have some troubles while writing logs from log4net to the file. I seem to do all as described in manual, but that does not work. Here is my logging.config file:
Yury Pogrebnyak
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How do I use a GlobalContext property in a log4net appender name?

I'm trying to customise a log4net file path to use a property I have set in the log4net.GlobalContext.Properties dictionary. log4net.GlobalContext.Properties["LogPathModifier"] = "SomeValue"; I can see that this value is set correctly when…
Long Pham
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