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Created 02-18-2017 02:26 AM
I need to formate the namenode. So i use below command to formate the namenode.
./bin/hadoop namenode -format
When i run the above command it gives me ,it formatted below formatted.But my namenode is located in different directory.Why its formatting temp forlder namenode.
17/02/18 10:17:17 INFO common.Storage: Storage directory /tmp/hadoop-aruna/dfs/name has been successfully formatted.
Below is the my .bashrc file configuration
#SET Hadoop Related Envirment Variable export HADOOP_HOME=/home/aruna/hadoop-2.7.3 export HADOOP_CONF_DIR=/home/aruna/hadoop-2.7.3/etc/hadoop export HADOOP_MAPRED_HOME=/home/aruna/hadoop-2.7.3 export HADOOP_COMMON_HOME=/home/aruna/hadoop-2.7.3 export HADOOP_HDFS_HOME=/home/aruna/hadoop-2.7.3 export YARN_HOME=/home/aruna/hadoop-2.7.3 export HADOOP_COMMON_LIB_NATIVE_DIR=$HADOOP_HOME/lib/native export HADOOP_OPTS="-Djava.library.path=$HADOOP_HOME/lib/native" #Set Java Home export JAVA_HOME=/usr/lib/jvm/java-7-oracle export PATH=$PATH:/usr/lib/jvm/java-7-oracle/bin #Set Hadoop bin directory PATH export PATH=$PATH:/home/aruna/hadoop-2.7.3/bin export HADOOP_PID_DIR=/home/aruna/hadoop-2.7.3/hadoop2_data/hdfs/pid
normally namenode should be in below path.
/home/aruna/hadoop-2.7.3/hadoop2_data/hdfs/namenode
Created 02-18-2017 02:48 AM
The "hadoop namenode -format" command formats the specified NameNode. It starts the NameNode, formats it and then shut it down.
dfs.namenode.name.dir: Determines where on the local filesystem the DFS name node should store the name table(fsimage). If this is a comma-delimited list of directories then the name table is replicated in all of the directories, for redundancy. with default value ${hadoop.tmp.dir}/dfs/name.
dfs.datanode.data.dir: (default: file://${hadoop.tmp.dir}/dfs/data) - Determines where on the local filesystem an DFS data node should store its blocks.
hadoop.tmp.dir: "/tmp/hadoop-${user.name}" (Default) - A base for other temporary directories.
.
Please check the values of above parameters defined in your core-site.xml/hdfs-site.xml
.
Ref:
https://hadoop.apache.org/docs/r2.7.3/hadoop-project-dist/hadoop-common/core-default.xml
The Default values are determined as mentioned in the link:
<property>
<name>dfs.namenode.name.dir</name>
<value>file://${hadoop.tmp.dir}/dfs/name</value>
<description>Determines where on the local filesystem the DFS name node
should store the name table(fsimage). If this is a comma-delimited list
of directories then the name table is replicated in all of the
directories, for redundancy. </description>
</property>.
Created 03-04-2017 12:00 PM
@Aruna,
delete all files and directories in /home/aruna/hadoop-2.7.3/hadoop2_data/hdfs/datanode
restart the cluster.
Still if you are having problem,
Please follow these steps
1. create the following directories in hadoop-2.7.3.
name
data
2. add the following lines in hdfs-site.xml
<property> <name> dfs.namenode.name.dir </name> <value>file://home/aruna/hadoop-2.7.3/name</value> </property> <property> <name>dfs.datanode.data.dir</name> <value>file://home/aruna/hadoop-2.7.3/data</value> </property>
3. delete all log files in hadoop-2.7.3/logs
4. format namenode
5. start cluster
Still you have problem reply with log files
All the best