Camel 2.7 or better uses sfl4j which allows you to configure logging via, among others:
Camel 2.6 or lower uses commons-logging which allows you to configure logging via, among others:
Refer to the commons-logging user guide for a more complete overview of how to use and configure commons-logging.
The quick way to enable Log4j is to add log4j to your classpath or maven pom.xml. For example the following in your pom.xml should do the trick
Then to configure log4j you need to add a log4j.properties or log4j.xml to your classpath (so they go in a directory which is on your classpath).
Here's an example log4j.properties file