Is there a log4net pattern for machineName [duplicate] - log4net

Question

This question already has answers here:
How do you log the machine name via log4net?
(2 answers)
Closed 3 years ago.
I'm having a hard time finding documentation on the various 'in the box' patterns like
%logger
%level
%timestamp
There is of course the example page but I'm not sure that's the full list of options.
I also know that it's possible to MDC parameters out of the app to the logger, but that involves a code change which is a different beast than a config change.
Is there a %machineName option, or machineIP option? The issue is that we have all our servers in the web farm log into the same database log, and we're now thinking that a disproportionate number of messages are coming from one machine.

Answer 1

%property{log4net:HostName}

Answer 2

What I did just stumble across is
<layout type="log4net.Layout.PatternLayout" value="${COMPUTERNAME}"/>
and that seems to be working --- wonder what the difference is between this and the other options suggested. like %property{log4net:HostName}

Answer 3

Create a class that gets the machine name:
using System;
using System.IO;
using log4net.Layout.Pattern;
namespace YourNameSpace.Converters
{
public class MachinePatternConverter : PatternLayoutConverter
{
protected override void Convert(TextWriter writer, log4net.Core.LoggingEvent loggingEvent)
{
writer.Write(Environment.MachineName);
}
}
}
then set your log4net configuration like this:
<layout type="log4net.Layout.PatternLayout">
<converter>
<name value="machine" />
<type value="YourNameSpace.MachinePatternConverter" />
</converter>
<conversionPattern value="%date [%thread] %level %logger %machine" />
</layout>
I like this approach as it can be reused and i can manage the information how i want. If you want to log the ip address for example, just do the same and create the converter like so:
public class IPPatternConverter : PatternLayoutConverter
{
protected override void Convert(TextWriter writer, log4net.Core.LoggingEvent loggingEvent)
{
if (HttpContext.Current == null)
return;
writer.Write(HttpContext.Current.Request.UserHostAddress);
}
}
More info on the link: http://devstuffs.wordpress.com/2012/01/12/creating-your-own-pattern-layout-converter-for-log4net/

Answer 4

Using this answer https://stackoverflow.com/a/2096452/1224858 about adding GlobalContext properties, I was able to get this to work.
I added the following code in my class file:
log4net.GlobalContext.Properties["hostname"] = Environment.MachineName;
And then in the config file I can reference hostname and it will appear
<layout type="log4net.Layout.PatternLayout">
<conversionPattern value="%date [%thread] %-5level %logger [%property{hostname}] - %message%newline" />
</layout>
Hope this helps.

Answer 5

Check out the PatternString API, it looks like you would need to use %property in your pattern. Also take a look at this article, you may need to inject the machine name into the global context on application startup.

Answer 6

Interesting, I think this is the "Compact Parameter Syntax" check out the last section over here http://logging.apache.org/log4net/release/manual/configuration.html