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HBase >> mail # user >> MapReduce vs hosts (Cannot resolve the host name)


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MapReduce vs hosts (Cannot resolve the host name)
Hi,

I'm facing a small issue, most probably configuration related, that
I'm not able to solve.

I'm trying to run the rowcounter.

Here is the command line:
export HADOOP_HOME=/home/hadoop/hadoop-1.0.3/; export
HBASE_HOME=/home/hbase/hbase-0.94.0/;
HADOOP_CLASSPATH=`${HBASE_HOME}/bin/hbase classpath`
${HADOOP_HOME}/bin/hadoop jar ${HBASE_HOME}/hbase-0.94.0.jar
rowcounter work_proposed -Dhbase.client.scanner.cachi=10

I'm getting errors for each of my regions:
12/10/11 09:10:45 ERROR mapreduce.TableInputFormatBase: Cannot resolve
the host name for /192.168.23.9 because of
javax.naming.NameNotFoundException: DNS name not found [response code
3]; remaining name '9.23.168.192.in-addr.arpa'

I have 25 regions for this table, so I have 25 lines like that.

And then it's blocking at:
12/10/11 09:10:45 INFO mapred.JobClient: Running job: job_201209151131_0005
12/10/11 09:10:46 INFO mapred.JobClient:  map 0% reduce 0%

Here is an extract of my host file:
192.168.23.9    node5
192.168.23.8    node4
192.168.23.7    node3
192.168.23.6    node2
192.168.23.5    node1

Hadoop is working fine.
HBase is working fine.

If I try the shell and do a count, it's working fine.

If I try with bin/hbase org.apache.hadoop.hbase.mapreduce.RowCounter
work_proposed it's working fine, but it's doing the regions one by
one, and not in parallel. So it's very slow.

I can ping the nodes, by name or IPs, I can ssh them too.

Any idea where I can start to look at?

Thanks,

JM