I am also having the same problem after I created directory and move the jar to the plugin folder: Here is the details:   You can see I have the .jar file in the right lib folder:       My environment variables are:   export FLUME_HOME=/opt/flume export FLUME_CONF_DIR=$FLUME_HOME/conf export FLUME_CLASSPATH=$FLUME_HOME_DIR export PATH=$FLUME_HOME/bin:$PATH and I am doing this under root user, below is the error message:   16/06/28 10:48:21 ERROR node.PollingPropertiesFileConfigurationProvider: Failed to load configuration data. Exception follows. org.apache.flume.FlumeException: Unable to load source type: com.cloudera.flume.source.TwitterSource, class: com.cloudera.flume.source.TwitterSource at org.apache.flume.source.DefaultSourceFactory.getClass(DefaultSourceFactory.java:67) at org.apache.flume.source.DefaultSourceFactory.create(DefaultSourceFactory.java:40) at org.apache.flume.node.AbstractConfigurationProvider.loadSources(AbstractConfigurationProvider.java:327) at org.apache.flume.node.AbstractConfigurationProvider.getConfiguration(AbstractConfigurationProvider.java:102) at org.apache.flume.node.PollingPropertiesFileConfigurationProvider$FileWatcherRunnable.run(PollingPropertiesFileConfigurationProvider.java:140) at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511) at java.util.concurrent.FutureTask.runAndReset(FutureTask.java:308) at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.access$301(ScheduledThreadPoolExecutor.java:180) at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:294) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617) at java.lang.Thread.run(Thread.java:745) Caused by: java.lang.ClassNotFoundException: com.cloudera.flume.source.TwitterSource at java.net.URLClassLoader.findClass(URLClassLoader.java:381) at java.lang.ClassLoader.loadClass(ClassLoader.java:424) at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:331) at java.lang.ClassLoader.loadClass(ClassLoader.java:357) at java.lang.Class.forName0(Native Method) at java.lang.Class.forName(Class.java:264) at org.apache.flume.source.DefaultSourceFactory.getClass(DefaultSourceFactory.java:65)   Can anyone shed any light on this with me? Thank you very much. ... View more