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This article mainly introduces "how to solve the failure of NN execution in hadoop coulud deployment". In the daily operation, I believe that many people have doubts about how to solve the problem of NN execution failure in hadoop coulud deployment. The editor has consulted all kinds of materials and sorted out simple and easy-to-use operation methods. I hope it will be helpful to answer the doubt of "how to solve the failure of NN execution in hadoop coulud deployment". Next, please follow the editor to study!

Recently, I encountered a headache in the deployment of hadoop-cloudera-beta2.

Execution of hdfs namenode-bootstrapStandby from NN always fails with the following exception:

Org.apache.hadoop.hdfs.server.common.Storage: Lock on / u0_pool/hadoop-hadoop/dfs/name/in_use.lock acquired by nodename 4654@warehouse1 2013-08-13 06 u0_pool/hadoop-hadoop/dfs/name/in_use.lock acquired by nodename 4654@warehouse1 35448 INFO org.apache.hadoop.hdfs.server.common.Storage: Locking is disabled 2013-08-13 06 org.apache.hadoop.hdfs.server.common.Storage 35487 INFO org.apache.hadoop.metrics2.impl.MetricsSystemImpl: Stopping NameNode metrics system... 2013-08-13 06 INFO org.apache.hadoop.metrics2.impl.MetricsSystemImpl: NameNode metrics system stopped. 2013-08-13 06 INFO org.apache.hadoop.metrics2.impl.MetricsSystemImpl: NameNode metrics system shutdown complete. 2013-08-13 06 FATAL org.apache.hadoop.hdfs.server.namenode.NameNode: Exception in namenode join org.apache.hadoop.hdfs.server.common.InconsistentFSStateException: Directory / u1_pool/namenode is in an inconsistent state: namespaceID is incompatible with others. At org.apache.hadoop.hdfs.server.common.Storage.setNamespaceID (Storage.java:1090) at org.apache.hadoop.hdfs.server.common.Storage.setFieldsFromProperties (Storage.java:888)

The format is not successful. As for why it is not successful, it may be a permission problem or other processes are using it.

The solution is to change the dir.name of the main NN. Copy the current under to the same directory folder from NN and run the above command again.

From this, we can see that in fact, the configuration of HA master and slave NN holds the same metadata. The client accesses the nameservice domain name space and looks for the NN in the Active state through the domain name space. It can be considered that it is actually a NN. If it is possible to ensure that two NN hold the same metadata, then QJM is used.

At this point, the study on "how to solve the failure of NN execution in hadoop coulud deployment" is over. I hope to be able to solve your doubts. The collocation of theory and practice can better help you learn, go and try it! If you want to continue to learn more related knowledge, please continue to follow the website, the editor will continue to work hard to bring you more practical articles!

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