Selenium: running testsuite in parallel using grid - selenium

Question

I am trying to execute the same testsuite in parallel on an arbitrary number of selenium-grid nodes.
The test suite was created with the selenium IDE and exported as testng using the batch-converter
The idea is to create the test-suite once and then launch an arbitrary number of nodes that run that particular suite in parallel
Right now, I got 1 hub running + 2 remote-controls connected to that hub
My testng.xml looks like this
<suite name="mysuite1" verbose="20" annotations="JDK" parallel="tests" thread-count="20" >
<parameter name="selenium.host" value="localhost"></parameter>
<parameter name="selenium.port" value="4444"></parameter>
<parameter name="selenium.browser" value="*firefox"></parameter>
<parameter name="selenium.restartSession" value="false"></parameter>
<test name="mytest1" preserve-order="true">
<parameter name="selenium.port" value="5557"></parameter>
<parameter name="selenium.browser" value="*firefox"></parameter>
<parameter name="selenium.url" value="http://localhost:8080"></parameter>
<classes>
<class name="my.testsuite1" />
<class name="my.testsuite2" />
</classes>
</test>
The target I'm using in the build.xml looks like this
<target name="run-parallel" depends="compile" description="Run-Parallel">
<echo>${host}</echo>
<java classpathref="runtime.classpath" classname="org.testng.TestNG" failonerror="true">
<sysproperty key="java.security.policy" file="lib/testng.policy"/>
<sysproperty key="webSite" value="${webSite}" />
<sysproperty key="seleniumHost" value="${host}" />
<sysproperty key="seleniumPort" value="${port}" />
<sysproperty key="browser" value="${browser}" />
<arg value="-d" />
<arg value="${basedir}/target/reports" />
<arg value="-suitename" />
<arg value="suite1" />
<arg value="-parallel"/>
<arg value="tests"/>
<arg value="-threadcount"/>
<arg value="20"/>
<arg value="testng.xml"/>
</java>
My problem:
When I execute the testsuite above, only one remote-control executes the test while my second remote-control remains idle.
I know that I currently address the remote-controls directly using the "selenium.port", but I am searching for a way to avoid this rigid way of assigning tests to remote-controls
When I add additional elements, all the classes listed within the elements (my.testsuite1-4) are executed in a random order.
<test name="mytest2" preserve-order="true">
<parameter name="selenium.port" value="5558"></parameter>
<parameter name="selenium.browser" value="*firefox"></parameter>
<parameter name="selenium.url" value="http://localhost:8080"></parameter>
<classes>
<class name="my.testsuite3" />
<class name="my.testsuite4" />
</classes>
My question:
How can I define a testsuite properly so that it is scheduled on any number of running remote-controls?
Thanks!

Answer 1

All of your tests should access the Selenium Grid hub. The hub is responsible for dispatching to nodes based upon the requested capabilities. Once you run tests in parallel, you lose the ability to define execution order. Each test should be isolated. This includes any data you may need on your backend, such as DB modifications.