On Mon, Jan 07, 2008 at 08:24:36AM -0800, Lars George wrote: >Hi, > >Maybe someone here can help me with a rather noob question. Where do I >have to put my custom jar to run it as a map/reduce job? Anywhere and >then specifying the HADOOP_CLASSPATH variable in hadoop-env.sh? >
Once you have your jar and submit it for your job via the *hadoop jar* command the framework takes care of distributing the software for nodes on which your maps/reduces are scheduled: $ hadoop jar <custom_jar> <custom_args> The detail is that the framework copies your jar from the submission node to the HDFS and then copies it onto the execution node. Does http://lucene.apache.org/hadoop/docs/r0.15.1/mapred_tutorial.html#Usage help? Arun >Also, since I am using the Hadoop API already from our server code, it >seems natural to launch jobs from within our code. Are there any issue >with that? I assume I have to copy the jar files first and make them >available as per my question above, but then I am ready to start it from >my own code? > >I have read most Wiki entries and while the actual workings are >described quite nicely, I could not find an answer to the questions >above. The demos are already in place and can be started as is without >the need of making them available. > >Again, I apologize for being a noobie. > >Lars
