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Execute hadoop job remotely and programmatically

+1 vote
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My project required to execute a hadoop job remotely and the job requires some third-part libraries (jar files). I tried:
1. Copy these jar files to hdfs.
2. Copy them into the distributed cache using DistributedCache.addFileToClassPath so that hadoop can spread these jar files to each of the slave nodes.

However, my program still throws ClassNotFoundException. Indicating that some of the classes cannot be found when the job is running.

So I am lookinh:
1. What is the correct way to run a job remotely and programmatically while the job requires some third-party jar files.
2. I found DistributedCache is deprecated (Im using hadoop 1.2.0), what is the alternative class?

posted Dec 9, 2013 by Meenal Mishra

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out them in  a lib directory in the jar you pass to Hadoop and they will be found...
commented Dec 9, 2013 by Ahmed Patel

1 Answer

+1 vote

Please have a look at the -libjars option of the hadoop cmd. It tells the system what additional libs have to be sent to the cluster before the job can start. Each time you submit the job, this kind of distribution happens again. So its not a good idea for really large libs, those you should deploy on all nodes and than you have to configure the classpath of the JVMs running the tasks.

answer Dec 10, 2013 by Sonu Jindal
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