Error Solr dedup Error with output 255

Question

I am browsing some data from the internet using apache nutch 2.3. My version of solr is 4.10.3. Data is successfully scanned in hbase and indexed also in solr, but at the end (release stage) a Follwoing error appears in the console;

IndexingJob: done. SOLR dedup -> http://solr:8983/solr /home/crawler/nutch-2.3/bin/nutch solrdedup -D mapred.reduce.tasks=2 -D mapred.child.java.opts=-Xmx1000m -D mapred.reduce.tasks.speculative.execution=false -D mapred.map.tasks.speculative.execution=false -D mapred.compress.map.output=true http://solr:8983/solr Error running: /home/crawler/nutch-2.3/bin/nutch solrdedup -D mapred.reduce.tasks=2 -D mapred.child.java.opts=-Xmx1000m -D mapred.reduce.tasks.speculative.execution=false -D mapred.map.tasks.speculative.execution=false -D mapred.compress.map.output=true http://solr:8983/solr Failed with exit value 255. 

Where solr is the IP machine working with apache solr. In apache nutch log file the corresponding error (the following is in detail)

 2015-01-28 10:39:47,830 WARN mapred.FileOutputCommitter - Output path is null in cleanup 2015-01-28 10:39:47,830 WARN mapred.LocalJobRunner - job_local345700287_0001 java.lang.Exception: java.lang.NullPointerException at org.apache.hadoop.mapred.LocalJobRunner$Job.run(LocalJobRunner.java:354) Caused by: java.lang.NullPointerException at org.apache.hadoop.io.Text.encode(Text.java:388) at org.apache.hadoop.io.Text.set(Text.java:178) at org.apache.nutch.indexer.solr.SolrDeleteDuplicates$SolrRecordReader.nextKeyValue(SolrDeleteDuplicates.java:233) at org.apache.hadoop.mapred.MapTask$NewTrackingRecordReader.nextKeyValue(MapTask.java:531) at org.apache.hadoop.mapreduce.MapContext.nextKeyValue(MapContext.java:67) at org.apache.hadoop.mapreduce.Mapper.run(Mapper.java:144) at org.apache.hadoop.mapred.MapTask.runNewMapper(MapTask.java:764) at org.apache.hadoop.mapred.MapTask.run(MapTask.java:364) at org.apache.hadoop.mapred.LocalJobRunner$Job$MapTaskRunnable.run(LocalJobRunner.java:223) at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511) at java.util.concurrent.FutureTask.run(FutureTask.java:266) 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) 

What is the problem with nutch or solr? How to do it?