Running a Cascading application is the same as running any Hadoop
application. After packaging your application into a single jar (see
Building), you must use
bin/hadoop
to submit the application to the
cluster.
For example, to execute an application stuffed into
your-application.jar
, call the Hadoop shell
script:
Example 4.2. Running a Cascading Application
$HADOOP_HOME/bin/hadoop jar your-application.jar [some params]
If the configuration scripts in $HADOOP_CONF_DIR
are configured to use a cluster, the Jar is pushed into the cluster for
execution.
Cascading does not rely on any environment variables like
$HADOOP_HOME
or $HADOOP_CONF_DIR
, only
bin/hadoop
does.
It should be noted that even though
your-application.jar
is passed on the command line
to bin/hadoop
, this in no way configures Hadoop to
push this jar into the cluster. You must still call one of the property
setters mentioned above to set the proper path to the application jar.
If misconfigured, it's likely that one of the internal libraries (found
in the lib folder) will be pushed to the cluster instead, and "Class Not
Found" exceptions will be thrown.
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