1. From server side:
In the services-config.xml, set the logging level to debug, and set filters to include the service you need:

<target class=”flex.messaging.log.ConsoleTarget” level=”debug”>
<properties>
<prefix>[Flex hotfix2] </prefix>
<includeDate>true</includeDate>
<includeTime>true</includeTime>
<includeLevel>true</includeLevel>
<includeCategory>true</includeCategory>
</properties>
<filters>
<pattern>Endpoint.*</pattern>
<pattern>Service.*</pattern>
<pattern>Protocol.*</pattern>
<pattern>Message.*</pattern>
<pattern>DataService.*</pattern>
<pattern>Configuration</pattern>
</filters>
</target>

See available pattern in doc:

http://livedocs.adobe.com/livecycle/8.2/programLC/programmer/lcds/help.html?content=services_logging_3.html

2. To turn on trace in JGroup:
in jgroups-tcp.xml, add <TRACE/> tag just before the </config> line :

<config>
….
<TRACE/>
</config>

3. To turn on from client-side:
Make sure flashlog.txt is enabled, i.e, have the following setting in mm.cfg
TraceOutputFileEnable=1
ErrorReportingEnable=1
See more details in the doc here
There is a good blog regarding mm.cfg here as well.
Then in your flex app, add the following tag:
<mx:TraceTarget/>

4. To turn on the flash player policy logging
see http://www.adobe.com/devnet/flashplayer/articles/fplayer9_security_05.html

Original post

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