@VLu,
Assuming you like the criteria being used for the persistent transaction trace, yup, that's basically it! Luckily, no development knowledge is required; here are the exact steps that I recommend following (step 3 is the only one your question didn't seem to include, and I'd say that it's the most important):
[list=1]
[*]Create an empty file: [font=Courier New]<EM_HOME>/config/PersistentTransactionTracerConfiguration.xml[font]
[*]Paste the sample XML from my post into the file.
[*]Review the [font=Courier New]TraceSession[font] and [font=Courier New]TransactionFilter[font] tags. Right now, this file will turn on transaction tracing for every agent with transactions lasting more than 5,000 milliseconds (5 seconds). In your case, you might want to select specific agents or use different transaction filtering criteria. The goal is to not add too much overhead to the Agents and to not overload the traces database. The XML schema I provided earlier shows what other kind of filter options are available (you can combine multiple filters and use basic Boolean AND/OR logic), but if you aren't sure, just post the logic you want to use in plain English and I'll see if I can convert it to working XML for this file.
[*]Save the file.
[*]Restart the Enterprise Manager.
[list] Even if you
do like the current criteria being used, I still recommend reviewing the filtering logic and XML tags being used so that get familiar with the syntax and any future updates to this file will be easier.
As for the XML schema, it may look scary, but it does contain useful information. For instance, you can specify transaction trace sessions for only transactions that encounter a specific error, contain a particular HTTP Request parameter, or exclude certain agents from an otherwise all-inclusive agent selection. In short, what the schema says is that something like the below should work just fine for the [font=Courier New]PersistentTransactionTracerConfiguration.xml[font] file contents:
<PersistentTracerConfiguration xmlns:jaxb="http://java.sun.com/xml/ns/jaxb" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="C:\cygwin\src\wailea\engineering\products\introscope\source\com\wily\introscope\server\enterprise\entity\transactiontrace\PersistentTransactionTrace0.1.xsd">
<!-- capture traces for all agents -->
<TraceSession agentExpression=".*" enabled="true">
<OrFilter>
<AndFilter>
<!-- capture traces with a duration that exceeds 5 seconds AND encouter the 404 error-->
<ThresholdFilter thresholdInMillis="5000"/>
<ErrorFilter errorString="HTTP Error Code: 404: /resources/favicon.ico"/>
<!-- but don't do this trace if the tranaction has an HTTP Request Paramter exactly matching X-Forwarded-Proto with the value https -->
<NotFilter>
<ParameterFilter parameterName="X-Forwarded-Proto" parameterValue="https" operationType="0">
</NotFilter>
</AndFilter>
<AndFilter>
<!-- capture traces for any transaction with a duration that exceeds 15 seconds and has not been flagged as a Stalled Transaction-->
<ThresholdFilter thresholdInMillis="15000"/>
<NotFilter>
<ErrorFilter errorString="Stalled Transaction"/>
</NotFilter>
</AndFilter>
</OrFilter>
</TraceSession>
<!-- capture traces for over 10 seconds for Agent A -->
<TraceSession agentExpression=".*Agent A" enabled="true">
<ThresholdFilter thresholdInMillis="10000"/>
</TraceSession>
</PersistentTracerConfiguration>