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Nlog logs location overwritten by code still logging happening at config location

NLog version - 4.4.3
Platform - .Net 4.5.2
Current NLog config -
<nlog autoReload="true" xmlns="http://www.nlog-project.org/schemas/NLog.xsd" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<variable name="layout" value="${longdate}|${level:uppercase=true}|${threadid}|${logger}|${message}" />
<variable name="logLocation" value="logs" />
<targets async="true">
<target name="debugger" xsi:type="Debugger" layout="${layout}" />
<target name="console" xsi:type="Console" layout="${layout}" />
<target name="logfile"
xsi:type="File"
fileName="${logLocation}\${processname}.log"
archiveFileName="${logLocation}\\${processname}.{###}.log"
archiveEvery="Day"
archiveAboveSize="2048000"
archiveNumbering="Rolling"
maxArchiveFiles="10"
concurrentWrites="false"
keepFileOpen="false"
layout="${layout}" />
</targets>
<rules>
<logger name="*" minlevel="Info" writeTo="logfile" />
<logger name="*" minlevel="Debug" writeTo="debugger" />
<logger name="*" minlevel="Info" writeTo="console" />
</rules>
</nlog>
Code to override location
LogManager.ReconfigExistingLoggers();
var target = (FileTarget)LogManager.Configuration.FindTargetByName<AsyncTargetWrapper>("logfile").WrappedTarget;
target.FileName = $#"..\..\..\..\logs\Foobar.log";
What is the current result?
When application/service starts it writes to overwritten location, but sometimes (not sure of scenario - maybe rollover) it start writing to config location.
What is the expected result?
Logs should always be written to overwritten location.
Did you checked the Internal log?
No
Please post full exception details (message, stacktrace, inner exceptions)
No Exception
Are there any workarounds? yes/no
Restart service/application.
Is there a version in which it did work?
No idea. This is the version we started with and sticking to.
Can you help us by writing an unit test?
Unit tests won't help as it is an intermittent scenario.

You have auto reload (<nlog autoReload="true”) enabled, so if it needs to reload (after sleep or change in config), you will lose the changes made in code.
The solution it so disable autoreload, or set the change after reload again. See code example:
static void Main(string[] args)
{
UpdateNLogConfig();
LogManager.ConfigurationReloaded += LogManager_ConfigurationReloaded;
log.Info("Entering Application.");
Console.WriteLine("Press any key to exit ...");
Console.Read();
}
private static void LogManager_ConfigurationReloaded(object sender, LoggingConfigurationReloadedEventArgs e)
{
UpdateNLogConfig();
}
private static void UpdateNLogConfig()
{
//note: don't set LogManager.Configuration because that will overwrite the nlog.config settings
var target = (FileTarget)LogManager.Configuration.FindTargetByName<AsyncTargetWrapper>("logfile").WrappedTarget;
target.FileName = $#"..\..\..\..\logs\Foobar.log";
LogManager.ReconfigExistingLoggers();
}
See also Combine XML config with C# config · NLog/NLog Wiki

Instead of doing target lookup, and modifying target properties directly. Then I suggest making use of the NLog Layout Logic.
<nlog autoReload="true" xmlns="http://www.nlog-project.org/schemas/NLog.xsd" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<targets async="true">
<target name="logfile"
xsi:type="File"
fileName="${gdc:item=logFile:whenEmpty=log/${processname}.log}" />
</targets>
<rules>
<logger name="*" minlevel="Info" writeTo="logfile" />
</rules>
</nlog>
And then just assign the logLocation:
NLog.GlobalDiagnosticsContext.Set("logFile", $#"..\..\..\..\logs\Foobar.log");
Using GDC will also works very well with autoReload=true and no need to call LogManager.ReconfigExistingLoggers().

How to programmatically configure nLog targets

I am trying to figure out how to programatically configure a NLog FallbackGroup target that has two email type sub-targets. Based on some things that happen during the start of the application, I would like to override the "to" part of the two sub-targets of the FallbackGroup target.
Currently, the app has a NLog.config file that has these targets in it. But, the values are hard-coded in it. Any change will require a redeploy of the app... That's not what we want... What we really need is the ability to modify the "to" setting in the two targets in some logic called on startup.
Here's the NLog.config file:
<?xml version="1.0" encoding="utf-8" ?>
<nlog xmlns="http://www.nlog-project.org/schemas/NLog.xsd"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://www.nlog-project.org/schemas/NLog.xsd NLog.xsd"
autoReload="true"
throwExceptions="false"
internalLogLevel="Off" internalLogFile="c:\temp\nlog-internal.log">
<targets>
<target name="logfile" xsi:type="File" fileName="BAM_logfile.txt" />
<target xsi:type="FallbackGroup"
name="email-error"
returnToFirstOnSuccess="true">
<target xsi:type="Mail"
name="mailserver1"
to="kevin.orcutt#acme.com"
from="noreply#acme.com"
subject="Exception Message from: ${processname} v:${assembly-version} on ${machinename}"
smtpServer="smtp.acme.com"
smtpPort="25"
layout="${longdate}${newline}${windows-identity} running ${processname} v:${assembly-version} on ${machinename}${newline}At: ${callsite}${newline}Message: ${message}${newline}Exception:${newline}${exception:format=toString,Data:maxInnerExceptionLevel=10}${newline}" />
<target xsi:type="Mail"
name="mailserver2"
to="kevin.orcutt#acme.com"
from="noreply#acme.com"
subject="Exception Message from: ${processname} v:${assembly-version} on ${machinename}"
smtpServer="mail.acme.com"
smtpPort="25"
layout="${longdate}${newline}${windows-identity} running ${processname} v:${assembly-version} on ${machinename}${newline}At: ${callsite}${newline}Message: ${message}${newline}Exception:${newline}${exception:format=toString,Data:maxInnerExceptionLevel=10}${newline}" />
</target>
</targets>
<rules>
<logger name="*" minlevel="Info" maxlevel="Warn" writeTo="logfile" />
<logger name="*" level="Error" writeTo="email-error" />
</rules>
<extensions>
<add assembly="NLog.MailKit"/>
</extensions>
</nlog>
So my question is... Is there a way of overriding the "to" part of the sub-targets in the NLog.config file programatically, or is it best to configure the entire FallbackGroup target on application start? A second and less obvious question is I'm looking for some examples of either solution... I haven't quite figured out the code to do either... :-(

It works something like this:
Load the configuration from the appropriate XML file. This can be your app.config or a separate XML file. Then find the target by name, and cast it to the appropriate type. From there you can modify its properties however you see fit.
var xmlConfig = new XmlLoggingConfiguration("nlog.config");
var target = xmlConfig.FindTargetByName("mailserver1") as MailTarget;
target.To = "...";
You can do this with any target: load it by name, then cast it to the appropriate type. When you're done making changes, apply the configuration:
LogManager.Configuration = xmlConfig;
This should be done at startup, before you get any loggers. I think any loggers you get before applying these changes will not be affected.

NLog: Where is NLog Config?

I coded this:
private static readonly ILogger Logger = LogManager.GetCurrentClassLogger();
public MyClass()
{
Console.Write("lol");
Logger.Debug("Debug test...");
Logger.Error("Debug test...");
Logger.Fatal("Debug test...");
Logger.Info("Debug test...");
Logger.Trace("Debug test...");
Logger.Warn("Debug test...");
}
And nothing displays.. so I was told to go and add <targets> to the config file, thing is.. where is the config file? Nothing on google, the documentation, or anything like that helps me...

From NLog Wiki:
The following locations will be searched when executing a stand-alone *.exe application:
standard application configuration file (usually applicationname.exe.config)
applicationname.exe.nlog in application’s directory
NLog.config in application’s directory
NLog.dll.nlog in a directory where NLog.dll is located (only if NLog isn't installed in the GAC)
So, the easiest would be to add a NLog.config file in the application’s directory

Sample Nlog.config File for your reference:
<?xml version="1.0" encoding="utf-8" ?>
<nlog xmlns="http://www.nlog-project.org/schemas/NLog.xsd"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
throwConfigExceptions="true">
<targets>
<target name="logfile" xsi:type="File" fileName="file.txt" />
<target name="logconsole" xsi:type="Console" />
</targets>
<rules>
<logger name="*" minlevel="Info" writeTo="logconsole" />
<logger name="*" minlevel="Debug" writeTo="logfile" />
</rules>
</nlog>
See also: https://github.com/NLog/NLog/wiki/Tutorial

Alternatively you can define the config programmatically in C# as explained in the blog docs here:
https://github.com/NLog/NLog/wiki/Configure-from-code

Nlog log file is not created

I am trying to log exceptions in console application. I have done everything as always (and then it worked for me...):
NLog.config:
<?xml version="1.0" encoding="utf-8" ?>
<nlog xmlns="http://www.nlog-project.org/schemas/NLog.xsd"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://www.nlog-project.org/schemas/NLog.xsd NLog.xsd"
autoReload="true"
throwExceptions="false"
internalLogLevel="Off" internalLogFile="c:\temp\nlog-internal.log">
<targets>
<target name="LogFile" xsi:type="File"
fileName="${basedir}/Log/${date:format=yyyyMMdd} myLog.txt"
layout="${longdate}|${level:uppercase=true}|${message}|${exception}" />
</targets>
<rules>
<logger name="*" minlevel="Debug" writeTo="LogFile" />
</rules>
</nlog>
class Program
{
private static Logger _log = LogManager.GetCurrentClassLogger();
static void Main(string[] args)
{
_log.Error("test");
}
}
For some mysterious reason file is never created nowhere on my computer. Any ideas why

Your config looks valid, so that shouldn't be the issue.
Some things to check:
Is you nlog.config in the correct directory? The best way to test is to copy the nlog.config to the directory with your .dll or .exe.
Enable exceptions to be sure that errors are not captured by Nlog: throwExceptions="true"
Check the internal log by setting internalLogLevel="Info" and check "c:\temp\nlog-internal.log"
A full tutorial to troubleshoot could be found on the NLog documentation.

In Visual Studio, check if your NLog.config file has this properties:
Build Action: Content.
Copy to Output Directory = Copy if newer
I am attaching a screen shot where you can see how it should appear. Sorry, it is in Spanish.

Edit your NLog config, change your log file path like this,use ${shortdate} instead {date:format=yyyyMMdd}. Set name in rules and call it like in this sample.
<?xml version="1.0" encoding="utf-8"?>
<nlog xmlns="http://www.nlog-project.org/schemas/NLog.xsd"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<targets async="true">
<targets>
<target name="LogFile" xsi:type="File"
fileName="${basedir}/Log/${shortdate}myLog.txt"
layout="${longdate}|${level:uppercase=true}|${message}|${exception}" />
</targets>
<rules>
<logger name="ErrorLog" minlevel="Trace" writeTo="LogFile" />
</rules>
</nlog>
And your .cs
class Program
{
private Logger ErrorLogger = NLog.LogManager.GetLogger("ErrorLog");
static void Main(string[] args)
{
ErrorLogger.Error("test");
}
}

Nlog logging methods

I am in the very alpha stage of a small website development project I am doing, and have decided to use NLog as my logging solution.
My solution is developed so far without logging. I am adding in the logging now.
An example:
private static Logger logger = LogManager.GetCurrentClassLogger();
public int SaveProject(ProjectDto project)
{
logger.Trace("SaveProject ({0}) : {1}", project.Id, _userId);
return _pb.SaveProject(project);
}
The 'GetCurrentClassLogger' method is great in that it now knows which class I am in.
But is there a way to report the Method name, instead of how I am doing it? In the example above, you can see I need to add "SaveProject" to the message. Is there a way to automatically get this? Or do I need to add this to every method logging call?

Yes, see the callsite layout renderer. You put it in your layout configuration. eg:
<?xml version="1.0" encoding="utf-8" ?>
<nlog xmlns="http://www.nlog-project.org/schemas/NLog.xsd" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<targets>
<target name="console" xsi:type="ColoredConsole" layout="${callsite:className=false:includeSourcePath=false:methodName=true} ${message}"/>
</targets>
<rules>
<logger name="*" minlevel="Trace" writeTo="console" />
</rules>
</nlog>