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org.apache.hadoop.hbase.client.NoServerForRegionException (ROOT region in transition)
I'm trying to import some data from mysql into hbase by using sqoop.
When the process running, i got the following error

13/07/23 12:38:58 INFO manager.MySQLManager: Preparing to use a MySQL streaming resultset.
13/07/23 12:38:58 INFO tool.CodeGenTool: Beginning code generation
13/07/23 12:38:59 INFO manager.SqlManager: Executing SQL statement: SELECT t.* FROM `pop` AS t LIMIT 1
13/07/23 12:38:59 INFO manager.SqlManager: Executing SQL statement: SELECT t.* FROM `pop` AS t LIMIT 1
13/07/23 12:38:59 INFO orm.CompilationManager: HADOOP_MAPRED_HOME is /usr/local/hadoops
Note: /tmp/sqoop-hduser/compile/61f2e4f1d24e82a26240a5f1d4872baf/pop.java

uses or overrides a deprecated API.
      Note: Recompile with -Xlint:deprecation for details.
      13/07/23 12:39:00 INFO orm.CompilationManager: Writing jar file: /tmp/sqoop-hduser/compile/61f2e4f1d24e82a26240a5f1d4872baf/pop.jar
      13/07/23 12:39:00 WARN manager.MySQLManager: It looks like you are importing from mysql.
      13/07/23 12:39:00 WARN manager.MySQLManager: This transfer can be faster! Use the --direct
      13/07/23 12:39:00 WARN manager.MySQLManager: option to exercise a MySQL-specific fast path.
      13/07/23 12:39:00 INFO manager.MySQLManager: Setting zero DATETIME behavior to convertToNull (mysql)
      13/07/23 12:39:00 INFO mapreduce.ImportJobBase: Beginning import of pop
      13/07/23 12:39:00 INFO zookeeper.ZooKeeper: Client environment:zookeeper.version=3.4.5-1392090, built on 09/30/2012 17:52
  GMT
      13/07/23 12:39:00 INFO zookeeper.ZooKeeper: Client environment:host.name=master
      13/07/23 12:39:00 INFO zookeeper.ZooKeeper: Client environment:java.version=1.7.0_15
      13/07/23 12:39:00 INFO zookeeper.ZooKeeper: Client environment:java.vendor=Oracle Corporation
      13/07/23 12:39:00 INFO zookeeper.ZooKeeper: Client environment:java.home=/usr/lib/jvm/jdk1.7.0/jre
      13/07/23 12:39:00 INFO zookeeper.ZooKeeper: Client environment:java.class.path=/usr/local/hadoops/libexec/../conf:/usr/lib/jvm/jdk1.7.0/lib/tools.jar:/usr/local/hadoops/libexec/..:/usr/local/hadoops/libexec/../hadoop-core-1.0.4.jar:/usr/local/hadoops/libexec/../lib/asm-3.2.jar:/usr/local/hadoops/libexec/../lib/aspectjrt-1.6.5.jar:/usr/local/hadoops/libexec/../lib/aspectjtools-1.6.5.jar:/usr/local/hadoops/libexec/../lib/commons-beanutils-1.7.0.jar:/usr/local/hadoops/libexec/../lib/commons-beanutils-core-1.8.0.jar:/usr/local/hadoops/libexec/../lib/commons-cli-1.2.jar:/usr/local/hadoops/libexec/../lib/commons-codec-1.4.jar:/usr/local/hadoops/libexec/../lib/commons-collections-3.2.1.jar:/usr/local/hadoops/libexec/../lib/commons-configuration-1.6.jar:/usr/local/hadoops/libexec/../lib/commons-daemon-1.0.1.jar:/usr/local/hadoops/libexec/../lib/commons-digester-1.8.jar:/usr/local/hadoops/libexec/../lib/commons-el-1.0.jar:/usr/local/hadoops/libexec/../lib/commons-httpclient-3.0.1.jar:/usr/local/hadoops/libexec/../lib/commons-io-2.1.jar:/usr/local/hadoops/libexec/../lib/commons-lang-2.4.jar:/usr/local/hadoops/libexec/../lib/commons-logging-1.1.1.jar:/usr/local/hadoops/libexec/../lib/commons-logging-api-1.0.4.jar:/usr/local/hadoops/libexec/../lib/commons-math-2.1.jar:/usr/local/hadoops/libexec/../lib/commons-net-1.4.1.jar:/usr/local/hadoops/libexec/../lib/core-3.1.1.jar:/usr/local/hadoops/libexec/../lib/hadoop-capacity-scheduler-1.0.4.jar:/usr/local/hadoops/libexec/../lib/hadoop-fairscheduler-1.0.4.jar:/usr/local/hadoops/libexec/../lib/hadoop-thriftfs-1.0.4.jar:/usr/local/hadoops/libexec/../lib/hsqldb-1.8.0.10.jar:/usr/local/hadoops/libexec/../lib/jackson-core-asl-1.8.8.jar:/usr/local/hadoops/libexec/../lib/jackson-mapper-asl-1.8.8.jar:/usr/local/hadoops/libexec/../lib/jasper-compiler-5.5.12.jar:/usr/local/hadoops/libexec/../lib/jasper-runtime-5.5.12.jar:/usr/local/hadoops/libexec/../lib/jdeb-0.8.jar:/usr/local/hadoops/libexec/../lib/jersey-core-1.8.jar:/usr/local/hadoops/libexec/../lib/jersey-json-1.8.jar:/usr/local/hadoops/libexec/../lib/jersey-server-1.8.jar:/usr/local/hadoops/libexec/../lib/jets3t-0.6.1.jar:/usr/local/hadoops/libexec/../lib/jetty-6.1.26.jar:/usr/local/hadoops/libexec/../lib/jetty-util-6.1.26.jar:/usr/local/hadoops/libexec/../lib/jsch-0.1.42.jar:/usr/local/hadoops/libexec/../lib/junit-4.5.jar:/usr/local/hadoops/libexec/../lib/kfs-0.2.2.jar:/usr/local/hadoops/libexec/../lib/log4j-1.2.15.jar:/usr/local/hadoops/libexec/../lib/mockito-all-1.8.5.jar:/usr/local/hadoops/libexec/../lib/oro-2.0.8.jar:/usr/local/hadoops/libexec/../lib/servlet-api-2.5-20081211.jar:/usr/local/hadoops/libexec/../lib/slf4j-api-1.4.3.jar:/usr/local/hadoops/libexec/../lib/slf4j-log4j12-1.4.3.jar:/usr/local/hadoops/libexec/../lib/xmlenc-0.52.jar:/usr/local/hadoops/libexec/../lib/jsp-2.1/jsp-2.1.jar:/usr/local/hadoops/libexec/../lib/jsp-2.1/jsp-api-2.1.jar:/usr/local/sqoops/bin/../conf::/usr/local/sqoops/bin/../lib/activation-1.1.jar:/usr/local/sqoops/bin/../lib/ant-contrib-1.0b3.jar:/usr/local/sqoops/bin/../lib/ant-eclipse-1.0-jvm1.2.jar:/usr/local/sqoops/bin/../lib/asm-3.1.jar:/usr/local/sqoops/bin/../lib/avro-1.5.3.jar:/usr/local/sqoops/bin/../lib/avro-ipc-1.5.3.jar:/usr/local/sqoops/bin/../lib/avro-mapred-1.5.3.jar:/usr/local/sqoops/bin/../lib/commons-beanutils-1.7.0.jar:/usr/local/sqoops/bin/../lib/commons-beanutils-core-1.8.0.jar:/usr/local/sqoops/bin/../lib/commons-cli-1.2.jar:/usr/local/sqoops/bin/../lib/commons-codec-1.4.jar:/usr/local/sqoops/bin/../lib/commons-collections-3.2.1.jar:/usr/local/sqoops/bin/../lib/commons-configuration-1.6.jar:/usr/local/sqoops/bin/../lib/commons-digester-1.8.jar:/usr/local/sqoops/bin/../lib/commons-el-1.0.jar:/usr/local/sqoops/bin/../lib/commons-httpclient-3.1.jar:/usr/local/sqoops/bin/../lib/commons-io-1.4.jar:/usr/local/sqoops/bin/../lib/commons-io-2.1.jar:/usr/local/sqoops/bin/../lib/commons-lang-2.5.jar:/usr/local/sqoops/bin/../lib/commons-logging-1.1.1.jar:/usr/local/sqoops/bin/../lib/commons-math-2.1.jar:/usr/local/sqoops/bin/../lib/commons-net-1.4.1.jar:/usr/local/sqoops/bin/../lib/core-3.1.1.jar:/usr/local/sqoops/bin/../lib/guava-11.0.2.jar:/usr/local/sqoops/bin/../lib/hadoop-core-1.0.4.jar:/usr/local/sqoops/bin/../lib/hbase-0.94.8.jar:/usr/local/sqoops/bin/../lib/high-scale-lib-1.1.1.jar:/usr/local/sqoops/bin/../lib/hsqldb-1.8.0.10.jar:/usr/local/sqoops/bin/../lib/httpclient-4.1.2.jar:/usr/local/sqoops/bin/../lib/httpcore-4.1.3.jar:/usr/local/sqoops/bin/../lib/jackson-core-asl-1.7.3.jar:/usr/local/sqoops/bin/../lib/jackson-core-asl-1.8.8.jar:/usr/local/sqoops/bin/../lib/jackson-jaxrs-1.8.8.jar:/usr/local/sqoops/bin/../lib/jackson-mapper-asl-1.7.3.jar:/usr/local/sqoops/bin/../lib/jackson-mapper-asl-1.8.8.jar:/usr/local/sqoops/bin/../lib/jackson-xc-1.8.8.jar:/usr/local/sqoops/bin/../lib/jamon-runtime-2.3.1.jar:/usr/local/sqoops/bin/../lib/jasper-compiler-5.5.23.jar:/usr/local/sqoops/bin/../lib/jasper-runtime-5.5.23.jar:/usr/local/sqoops/bin/../lib/jaxb-api-2.1.jar:/usr/local/sqoops/bin/../lib/jaxb-impl-2.2.3-1.jar:/usr/local/sqoops/bin/../lib/jersey-core-1.8.jar:/usr/local/sqoops/bin/../lib/jersey-json-1.8.jar:/usr/local/sqoops/bin/../lib/jersey-server-1.8.jar:/usr/local/sqoops/bin/../lib/jettison-1.1.jar:/usr/local/sqoops/bin/../lib/jetty-6.1.26.jar:/usr/local/sqoops/bin/../lib/jetty-util-6.1.26.jar:/usr/local/sqoops/bin/../lib/jopt-simple-3.2.jar:/usr/local/sqoops/bin/../lib/jruby-complete-1.6.5.jar:/usr/local/sqoops/bin/../lib/jsp-2.1-6.1.14.jar:/usr/local/sqoops/bin/../lib/jsp-api-2.1-6.1.14.jar:/usr/local/sqoops/bin/../lib/jsr305-1.3.9.jar:/usr/local/sqoops/bin/../lib/junit-4.10-HBASE-1.jar:/usr/local/sqoops/bin/../lib/libthrift-0.8.0.jar:/usr/local/sqoops/bin/../lib/log4j-1.2.16.jar:/usr/local/sqoops/bin/../lib/metrics-core-2.1.2.jar:/usr/local/sqoops/bin/../lib/mysql-connector-java-5.1.25-bin.jar:/usr/local/sqoops/bin/../lib/netty-3.2.4.Final.jar:/usr/local/sqoops/bin/../lib/paranamer-2.3.jar:/usr/local/sqoops/bin/../lib/protobuf-java-2.4.0a.jar:/usr/local/sqoops/bin/../lib/servlet-api-2.5-6.1.14.jar:/usr/local/sqoops/bin/../lib/slf4j-api-1.4.3.jar:/usr/local/sqoops/bin/../lib/slf4j-log4j12-1.4.3.jar:/usr/local/sqoops/bin/../lib/snappy-java-1.0.3.2.jar:/usr/local/sqoops/bin/../lib/stax-api-1.0.1.jar:/usr/local/sqoops/bin/../lib/velocity-1.7.jar:/usr/local/sqoops/bin/../lib/xmlenc-0.52.jar:/usr/local/sqoops/bin/../lib/zookeeper-3.4.5.jar:/usr/local/sqoops/bin/../sqoop-1.4.3.jar:/usr/local/sqoops/bin/../sqoop-test-1.4.3.jar:
      13/07/23 12:39:00 INFO zookeeper.ZooKeeper: Client environment:java.library.path=/usr/local/hadoops/libexec/../lib/native/Linux-amd64-64
      13/07/23 12:39:00 INFO zookeeper.ZooKeeper: Client environment:java.io.tmpdir=/tmp
      13/07/23 12:39:00 INFO zookeeper.ZooKeeper: Client environment:java.compiler=
      13/07/23 12:39:00 INFO zookeeper.ZooKeeper: Client environment:os.name=Linux
      13/07/23 12:39:00 INFO zookeeper.ZooKeeper: Client environment:os.arch=amd64
      13/07/23 12:39:00 INFO zookeeper.ZooKeeper: Client environment:os.version=3.5.0-23-generic
      13/07/23 12:39:00 INFO zookeeper.ZooKeeper: Client environment:user.name=hduser
      13/07/23 12:39:00 INFO zookeeper.ZooKeeper: Client environment:user.home=/home/hduser
      13/07/23 12:39:00 INFO zookeeper.ZooKeeper: Client environment:user.dir=/home/hduser
      13/07/23 12:39:00 INFO zookeeper.ZooKeeper: Initiating client connection, connectString=localhost:2181 sessionTimeout=180000
  watcher=hconnection
      13/07/23 12:39:00 INFO zookeeper.RecoverableZooKeeper: The identifier of this process is 6256@Master
      13/07/23 12:39:00 INFO zookeeper.ClientCnxn: Opening socket connection to server ip6-localhost/127.0.0.1:2181. Will not attempt to
  authenticate using SASL (unknown error)
      13/07/23 12:39:00 INFO zookeeper.ClientCnxn: Socket connection established to ip6-localhost/127.0.0.1:2181, initiating session
      13/07/23 12:39:00 INFO zookeeper.ClientCnxn: Session establishment complete on server ip6-localhost/127.0.0.1:2181, sessionid =
  0x14009b9169f0009, negotiated timeout = 180000
      13/07/23 12:39:00 INFO zookeeper.ZooKeeper: Initiating client connection, connectString=localhost:2181 sessionTimeout=180000
  watcher=catalogtracker-on-org.apache.hadoop.hbase.client.HConnectionManager$HConnectionImplementation@3b48a380
      13/07/23 12:39:00 INFO zookeeper.RecoverableZooKeeper: The identifier of this process is 6256@Master
      13/07/23 12:39:00 INFO zookeeper.ClientCnxn: Opening socket connection to server ip6-localhost/127.0.0.1:2181. Will not attempt to
  authenticate using SASL (unknown error)
      13/07/23 12:39:00 INFO zookeeper.ClientCnxn: Socket connection established to ip6-localhost/127.0.0.1:2181, initiating session
      13/07/23 12:39:00 INFO zookeeper.ClientCnxn: Session establishment complete on server ip6-localhost/127.0.0.1:2181, sessionid =
  0x14009b9169f000a, negotiated timeout = 180000
      13/07/23 12:49:01 INFO zookeeper.ZooKeeper: Session: 0x14009b9169f000a closed
      13/07/23 12:49:01 INFO zookeeper.ClientCnxn: EventThread shut down
      13/07/23 12:49:01 ERROR tool.ImportTool: Encountered IOException running import job:
  org.apache.hadoop.hbase.client.NoServerForRegionException: Unable to
  find region for  after 10 tries.
        at org.apache.hadoop.hbase.client.HConnectionManager$HConnectionImplementation.locateRegionInMeta(HConnectionManager.java:991)
        at org.apache.hadoop.hbase.client.HConnectionManager$HConnectionImplementation.locateRegion(HConnectionManager.java:896)
        at org.apache.hadoop.hbase.client.HConnectionManager$HConnectionImplementation.locateRegion(HConnectionManager.java:857)
        at org.apache.hadoop.hbase.client.HTable.finishSetup(HTable.java:233)
        at org.apache.hadoop.hbase.client.HTable.(HTable.java:173)
        at org.apache.hadoop.hbase.catalog.MetaReader.getHTable(MetaReader.java:201)
        at org.apache.hadoop.hbase.catalog.MetaReader.getMetaHTable(MetaReader.java:227)
        at org.apache.hadoop.hbase.catalog.MetaReader.fullScan(MetaReader.java:722)
        at org.apache.hadoop.hbase.catalog.MetaReader.fullScan(MetaReader.java:184)
        at org.apache.hadoop.hbase.catalog.MetaReader.tableExists(MetaReader.java:450)
        at org.apache.hadoop.hbase.client.HBaseAdmin.tableExists(HBaseAdmin.java:250)
        at org.apache.sqoop.mapreduce.HBaseImportJob.jobSetup(HBaseImportJob.java:194)
        at org.apache.sqoop.mapreduce.ImportJobBase.runImport(ImportJobBase.java:219)
        at org.apache.sqoop.manager.SqlManager.importTable(SqlManager.java:545)
        at org.apache.sqoop.manager.MySQLManager.importTable(MySQLManager.java:111)
        at org.apache.sqoop.tool.ImportTool.importTable(ImportTool.java:403)
        at org.apache.sqoop.tool.ImportTool.run(ImportTool.java:476)
        at org.apache.sqoop.Sqoop.run(Sqoop.java:145)
        at org.apache.hadoop.util.ToolRunner.run(ToolRunner.java:65)
        at org.apache.sqoop.Sqoop.runSqoop(Sqoop.java:181)
        at org.apache.sqoop.Sqoop.runTool(Sqoop.java:220)
        at org.apache.sqoop.Sqoop.runTool(Sqoop.java:229)
        at org.apache.sqoop.Sqoop.main(Sqoop.java:238)

In the 'regions in transition', i got the following information:
-ROOT-,,0.70236052 state=OFFLINE, ts=Tue Jul 23 12:42:08 WIT 2013 (594s ago), server=null
Can anyone please help me to solve this? I'm out of ideas.
I've got a presentation one week later.
Thank you for the kindness to help me.

Looks like some problem with your RegionServer. Perhaps, RegionServer's session has expired or it is dead and hence the HMaster is not able to assign the regions held by this RegionServer. Looking at the RegionServer logs would be helpful. You could probably see in HMaster logs where this region was assigned. Then go to that RegionServer's UI and see if you see the region?
BTW, How many nodes do you have?Is the data too huge to be stored in your current cluster?

Thanks for the help.
I have 4 nodes, 1 node acts as master and the others as slave.
Yes, my data is realtively nearly huge to be stored.
I have my -ROOT- region unassigned yesterday, it kept stuck in the "regions in transition".
And then, today I've started the master node to work as slave node too, and the import was a success.
I don't know what's wrong in the import process while the master node didn't act as a slave (the -ROOT- region kept unassigned, although i had tried some ways to solve that).

The problem solved by commenting out localhost (127.0.0.1) in /etc/hosts, and matching the hosts specified in there with which specified in /etc/hostname (in both master and regionservers)
