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:

4014 questions
27
votes
3 answers

log4net - configure using multiple configuration files

I have an application consisting of a host and pluggable modules (plugins). I want to be able to configure log4net for the host and for each of the other modules. Each of them should have its own configuration file and each will log to a different…
Gai
  • 325
  • 1
  • 5
  • 8
27
votes
2 answers

Log4Net and .NET 4.0 RC

I tried to compile a project dependent on the Log4Net logging framework using .NET 4.0 RC and ran into some problems. Out of the box (just changing the target to .NET 4.0), it no longer works, a security exception is thrown. Inheritance security…
vzczc
  • 9,270
  • 5
  • 52
  • 61
26
votes
5 answers

Enterprise Logging Block vs NLog vs log4net

I need to use a logging library in my project and considering between Enterprise Logging Block vs NLog vs log4net. I found some links on the comparison but most of those are quite old and complaint about things like no new versions of log4net for…
imak
  • 6,489
  • 7
  • 50
  • 73
26
votes
4 answers

How do I configure a RollingFileAppender to roll by date and size with log4net?

I am configure log4net to use a composite RollingFileAppender so that the current file is always named logfile.log and all subsequent files are named logfile-YYYY.MM.dd.seq.log where seq is the sequence number if a log exceeds a certain size within…
Ryan Taylor
  • 8,740
  • 15
  • 65
  • 98
26
votes
4 answers

log4net unique request id in ASP.NET

log4net 1.2.11.0 I am trying to get anything that will allow me to log with a unique value for each ASP.NET request. I tried %thread, but threads appear to be reused. I've tried %aspnet-request and %aspnet-session which don't have anything…
LiteWait
  • 584
  • 4
  • 21
  • 42
25
votes
7 answers

Using Ninject to fill Log4Net Dependency

I use Ninject as a DI Container in my application. In order to loosely couple to my logging library, I use an interface like this: public interface ILogger { void Debug(string message); void Debug(string message, Exception…
Brook
  • 5,949
  • 3
  • 31
  • 45
25
votes
5 answers

How can I include SessionID in log files using log4net in ASP.NET?

I'm new to log4net, so hopefully this is a really easy question for someone?! I've got log4net working with the RollingLogFileAppender for my web application. I'm using logging to try and find where some performance issues are coming from. In…
Chris Roberts
  • 18,622
  • 12
  • 60
  • 67
25
votes
1 answer

Log4net RollingFileAppender Size rollingStyle file extension

I am using the RollingFileAppender and the Size rollingStyle. By default it creates backup files with a numbered extension, this drives me nuts. Is it possible to change it so it always uses a defined extension (say .txt or .log) and inserts the…
BrettRobi
  • 3,793
  • 7
  • 40
  • 64
25
votes
2 answers

Best practice to include log4Net external config file in ASP.NET

I have seen at least two ways to include an external log4net config file in an ASP.NET web application: Having the following attribute in your AssemblyInfo.cs file: [assembly: log4net.Config.XmlConfigurator(ConfigFile = "Log.config", Watch =…
Martin Buberl
  • 45,844
  • 25
  • 100
  • 144
24
votes
9 answers

C# private, static, and readonly

I was reviewing some code for log4net and I came across this. private static readonly ILog logger = LogManager.GetLogger(typeof(AdminClient)); I am wondering why would you need to have private static readonly. From my understanding private would…
ant2009
  • 27,094
  • 154
  • 411
  • 609
24
votes
2 answers

Log4Net - Logging out the Exception stacktrace only for certain files

I currently have multiple log files in my application using log4net. I have a top level log file which contains every type of message. I also have an error log file which contains only error information. I am trying to configure it so the specific…
Rob
  • 1,407
  • 2
  • 15
  • 22
24
votes
3 answers

Why is log4net not recognized in configuration file?

I wrote a test console application in C# using log4net: using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Threading.Tasks; using log4net; using log4net.Config; [assembly:…
John Threepwood
  • 15,593
  • 27
  • 93
  • 149
24
votes
3 answers

Is log4net dead?

I'm looking for a logging framework and it seems log4net is or was very popular. The last release was over 2 years ago. It has not been updated for .net 3.0 or 3.5 or even visual studio 2008. Is there something more recent (other then entlib) I…
Chip
  • 262
  • 2
  • 6
24
votes
4 answers

Programmatically adding and removing log appenders in log4net

I have a component that uses log4net. I want to create unit tests, that validate that certain error conditions result in the correct logging. I was thinking that the best way to do this is to create an ILogAppender implementation, for example a…
Pete
  • 12,206
  • 8
  • 54
  • 70
24
votes
8 answers

Failed obtaining configuration for Common.Logging from configuration section 'common/logging'

I'm trying to configure a console application with the following logging assemblies: Common.Logging.dll (2.1.0.0) Common.Logging.Log4Net1211.dll (2.1.0.0) log4net.dll (1.2.11.0) If the logger gets configured programmatically then everything…
jdecuyper
  • 3,934
  • 9
  • 39
  • 51