By default Infinispan uses JBoss Logging 3.0 as logging framework. JBoss Logging acts as a delegator to either JBoss Log Manager, Apache Log4j, Slf4j or JDK Logging. The way it chooses which logging provider to delegate to is by:
checking whether the JBoss Log Manager is configured (e.g. Infinispan is running in JBoss Application Server 7) and if it is, using it
otherwise, checking if Apache Log4j is in the classpath (JBoss Logging checks if the classes org.apache.log4j.LogManager and org.apache.log4j.Hierarchy are available) and if it is, using it
otherwise, checking if LogBack in the classpath (JBoss Logging checks if the class ch.qos.logback.classic.Logger is available) and if it is, using it
finally, if none of the above are available, using JDK logging
You can use this log4j.xml as base for any Infinispan related logging, and you can pass it to your system via system parameter (e.g., -Dlog4j.configuration=file:/path/to/log4j.xml).