Big Data Analytics with Hadoop 3

Starting HDFS

Follow these steps as shown to start HDFS (NameNode and DataNode):

1. Format the filesystem:

$ ./bin/hdfs namenode -format

2. Start the NameNode daemon and the DataNode daemon:

$ ./sbin/start-dfs.sh

The Hadoop daemon log output is written to the $HADOOP_LOG_DIR directory (defaults to $HADOOP_HOME/logs).

3. Browse the web interface for the NameNode; by default it is available at http://localhost:9870/.
4. Make the HDFS directories required to execute MapReduce jobs:

$ ./bin/hdfs dfs -mkdir /user $ ./bin/hdfs dfs -mkdir /user/<username>

5. When you're done, stop the daemons with the following:

$ ./sbin/stop-dfs.sh

6. Open a browser to check your local Hadoop, which can be launched in the browser as http://localhost:9870/. The following ...