How can I create a new unique name jmeter.log file each time a CLI command is run?

Whenever I run a new jmeter command from the CLI a new jmeter.log file is generated and I lose the contents written by the previous test run.

Example:

First I run the test script with :

jmeter -n -p .\config.properties -t .\path\to\jmeterScripFile.jmx -l .\path\to\jmeterScriptOutputFile.jtl

This generates a fresh jmeter.log file.

Then I run this command to generate a HTML Dashboard report:

jmeter -g  .\path\to\jmeterScriptOutputFile.jtl  -o .\path\to\TestResults\ReportHTML

This 2nd command overrides the previous jmeter.log file's contents.

I would like each jmeter CLI command to generate a unique .log file. Something like jmeter-yyyymmdd-hhMMss

How could I achieve this?

Solution

Several ideas: Either provide a fresh filename as a startup option manually or edit logging config to do this for you automatically.

Manually

You can override the default jmeter.log file name using the -j command-line argument and add the timestamp via your operating system shell.

For example on Linux:

jmeter -j "jmeter.$(date +%s).log" -n -t .....

Automatically

If you want to make the change permanent and don't want to provide the new log file name via -j command-line argument then you can amend the log file prefix via the log4j2.xml file like so:

Change this line...

<File name="jmeter-log" fileName="${sys:jmeter.logfile:-jmeter.log}" append="false">

...to something like this:

<File name="jmeter-log" fileName="jmeter-${date:yyyyMMdd-hh-mm-ss}.log" append="false">

How can I create a new unique name jmeter.log file each time a CLI command is run?

Manually

Automatically

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