NLog: Custom target with async attribute get incorrect timestamp and order of logs

NLog version: 4.6.5

Platform: WebApi 2.1 .net47

Current NLog config

<nlog xmlns="http://www.nlog-project.org/schemas/NLog.xsd" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
  <targets async="true">
      <target name="graylogt" xsi:type="GraylogHttp" facility="WebApi" graylogServer="http://graylog" graylogPort="12201">
        <parameter name="current_user" layout="${aspnet-user-identity}" />
        <parameter name="exception_type" layout="${exception:Type}" />
        <parameter name="request" layout="${aspnet-request-method} ${aspnet-request-url}" />
        <parameter name="site" layout="${iis-site-name} ${aspnet-appbasepath}" />
        <parameter name="request_body" layout="${onexception:${aspnet-request-posted-body}:when=level>=LogLevel.Error}" />
      </target>
    </targets>
    <rules>
     <logger name="*" minlevel="debug" writeTo="graylogt" />
    </rules>
  </nlog>

Hi, I use a https://github.com/dustinchilson/NLog.Targets.GraylogHttp for graylog. In order to don’t block the thread for logging I use an async attribute. But logs have incorrect timestamps and order(compare to sync mode). I can’t use “sync” logs, because every log operation takes 0.2 sec.

What is the current result?

Incorrect order and timestamp of logs

What is the expected result?

Correct order and timestamps

About this issue

Original URL
State: closed
Created 5 years ago
Comments: 41 (22 by maintainers)

Most upvoted comments

Created PR https://github.com/farzadpanahi/NLog.GelfLayout/pull/14 for you. Introduces a new setting FixDuplicateTimestamp (Default = False)

Can handle bursts of 9 unique timestamps within the same millisecond:

If time-resolution is 16 millisecond, then it will support 500 msgs/sec. with unique timestamp.
If time-resolution is 1 millisecond (AccurateUTC), then it will support 9000 msgs/sec with unique timestamp.

snakefoot on Aug 24, 2019

So my final nlog-config is

<nlog xmlns="http://www.nlog-project.org/schemas/NLog.xsd" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
    <time type="AccurateUTC" />
    <extensions>
      <add assembly="NLog.Web" />
      <add assembly="NLog.Layouts.GelfLayout" />
    </extensions>
    <targets async="true">
      <target name="graylogt" xsi:type="network" address="tcp://graylog:12200" newLine ="true" lineEnding="Null" >
        <layout xsi:type="GelfLayout" facility="WebApi">
          <field name="current_user" layout="${aspnet-user-identity}" />
          <field name="exception_type" layout="${exception:Type}" />
          <field name="request" layout="${aspnet-request-method} ${aspnet-request-url}" />
          <field name="site" layout="${iis-site-name} ${aspnet-appbasepath}" />
          <field name="request_body" layout="${onexception:${aspnet-request-posted-body}:when=level>=LogLevel.Error}" />
        </layout>
      </target>
    </targets>
    <rules>
        <logger name="*" minlevel="debug" writeTo="graylogt" />
    </rules>
  </nlog>

and here is my graylog input

kirya522 on Dec 16, 2019

Happy the problem has been resolved. Could you post your final nlog-config for others to witness?

snakefoot on Aug 23, 2019

What happens if you configure keepConnection="True" and lineEnding="Null" ?

snakefoot on Aug 23, 2019