No log file (Java)

Problem

Your New Relic Java agent is not generating log files.

Solution

Ensure your New Relic Java agent is configured to generate newrelic_agent.log files by checking the following:

Log file directory

New Relic's Java agent stores log files in the logs directory. The Java agent creates this directory in the same location used for the newrelic.jar in the -javaagent switch. If you cannot find newrelic_agent.log, ensure the JVM process has permissions to write to the logs directory.

Permissions management varies greatly by environment, so work with your system administrator to verify that this is not an issue. If permissions are not the issue, check that you did not customize the location of the logs directory.

You can specify a different directory and name with the log_file_path and log_file_name settings.

Config file

Ensure that the YAML format in newrelic.yml is valid by using a YAML validator. This tool verifies that your YAML is valid. It also gives you an interpreted version uncluttered by comments.

If your YAML is not valid, use an editor that keeps spaces on lines, such as Sublime Text. This will help you make changes to your newrelic.yml with the correct number of spaces.

Boot log

You can start up your app server so that it prints to the console. Here are some examples of where this is stored:

  • JBoss: log/boot.log
  • Glassfish: domain-dir/logs/server.log
  • Tomcat: catalina.out (if specified in catalina.sh) or catalina.bat
  • WebLogic:server_name.log
  • WebObjects: /var/log/webobjects.log

When booting your JVM, verify that the generated logs show that the newrelic.jar file opened and that the Java agent interpreted the newrelic.yml configuration file. Failures to find either file or open them correctly will appear in the logs.

Successfully loading the agent will look something like this:

Aug 29, 2017 15:02:49 -0700 NewRelic 1 INFO: Agent is using Logback
Aug 29, 2017 15:02:49 -0700 NewRelic 1 INFO: Loading configuration file
"/path/on/your/host/newrelic/.newrelic.yml"

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