You are trying to run on Hadoop 2 and Mahout only works with Hadoop 1 and related branches. This wont work.
However the CDH distributions also come in an 'mr1' flavor that stands a much better chance of working with something that is built for Hadoop 1. Use 2.0.0-mr1-4.3.1 instead. (PS 4.3.2 and 4.4.0 are available now) You will likely still have to compile Mahout again with this different dependency to get it to work but with any luck that's it. Sean On Sep 10, 2013 6:34 PM, "Parimi Rohit" <rohit.par...@gmail.com> wrote: > Hi All, > > I am used to running mahout (mahout-core-0.9-SNAPSHOT-job.jar) in the > Apache Hadoop environment, however, we had to switch to Cloudera > distribution. > > When I try to run the item based collaborative filtering job > (org.apache.mahout.cf.taste.hadoop.item.RecommenderJob) in the Cloudera > distribution, I get the following error, > > Exception in thread "main" java.lang.IncompatibleClassChangeError: Found > interface org.apache.hadoop.mapreduce.JobContext, but class was expected > at > org.apache.mahout.common.HadoopUtil.getCustomJobName(HadoopUtil.java:174) > at > org.apache.mahout.common.AbstractJob.prepareJob(AbstractJob.java:614) > at > > org.apache.mahout.cf.taste.hadoop.preparation.PreparePreferenceMatrixJob.run(PreparePreferenceMatrixJob.java:75) > at org.apache.hadoop.util.ToolRunner.run(ToolRunner.java:70) > at > > org.apache.mahout.cf.taste.hadoop.item.RecommenderJob.run(RecommenderJob.java:158) > at org.apache.hadoop.util.ToolRunner.run(ToolRunner.java:70) > at > > org.apache.mahout.cf.taste.hadoop.item.RecommenderJob.main(RecommenderJob.java:312) > at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) > at > > sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57) > at > > sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) > at java.lang.reflect.Method.invoke(Method.java:606) > at org.apache.hadoop.util.RunJar.main(RunJar.java:208) > > Is there a way to run Mahout in the Cloudera environment? I mean, a > download specific to Cloudera distribution of Hadoop? > > Thanks in advance, > Rohit >
