Apache Hadoop
Apache Hadoop project develops open-source software for reliable, scalable, distributed computing.
The Apache Hadoop software library is a framework that allows for the distributed processing of large data sets across clusters of computers using simple programming models. It is designed to scale up from single servers to thousands of machines, each offering local computation and storage.
Hadoop modules:
- Hadoop Common
- The common utilities that support the other Hadoop modules.
- Hadoop Distributed File System (HDFS)
A distributed file system that provides high-throughput access to application data.
- Hadoop YARN
A framework for job scheduling and cluster resource management.
Hadoop MapReduce
A YARN-based system for parallel processing of large data sets.
Install
~/tmp/hadoop-3.3.1/etc/hadoop/hadoop-env.sh
1 export JAVA_HOME=/home/vitor/jdk-11.0.10+9
~/tmp/hadoop-3.3.1/etc/hadoop/core-site.xml
~/tmp/hadoop-3.3.1/etc/hadoop/hdfs-site.xml
1 <?xml version="1.0" encoding="UTF-8"?>
2 <?xml-stylesheet type="text/xsl" href="configuration.xsl"?>
3 <configuration>
4 <property>
5 <name>dfs.namenode.name.dir</name>
6 <value>/tmp/nameNode</value>
7 </property>
8 <property>
9 <name>dfs.namenode.data.dir</name>
10 <value>/tmp/dataNode</value>
11 </property>
12 <property>
13 <name>dfs.replication</name>
14 <value>2</value>
15 </property>
16 </configuration>
~/tmp/hadoop-3.3.1/etc/hadoop/mapred-site.xml
~/tmp/hadoop-3.3.1/etc/hadoop/yarn-site.xml
1 <?xml version="1.0"?>
2 <configuration>
3 <property>
4 <name>yarn.acl.enable</name>
5 <value>0</value>
6 </property>
7 <property>
8 <name>yarn.resourcemanager.hostname</name>
9 <value>master</value>
10 </property>
11 <property>
12 <name>yarn.nodemanager.aux-services</name>
13 <value>mapreduce_shuffle</value>
14 </property>
15 </configuration>
~/tmp/hadoop-3.3.1/etc/hadoop/slaves
1 localhost
~/.bashrc
Setup HDFS
1 ls $HADOOP_HOME/bin/
2 hdfs dfsadmin -report
3 # 2021-07-23 14:07:17,010 WARN fs.FileSystem: Failed to initialize fileystem hdfs://master:9000:
4 # java.lang.IllegalArgumentException: java.net.UnknownHostException: master
5 # report: java.net.UnknownHostException: master
6 # add 127.0.0.1 master to /etc/hosts
7 hdfs namenode -format master
8 hdfs --daemon start namenode
9 hdfs --daemon start datanode
10 yarn --daemon start resourcemanager
11 yarn --daemon start nodemanager
12 yarn --daemon start proxyserver
13 mapred --daemon start historyserver
14 hdfs dfsadmin -report
15 # http://localhost:9870/
16 # http://localhost:9870/dfshealth.html#tab-overview
17 # http://localhost:9870/explorer.html#
18 # http://localhost:8088/
19 # http://localhost:8088/cluster
20 # http://localhost:19888/
21 hadoop fs -ls /
22 hadoop fs -ls /tmp
23 hadoop fs -mkdir /test
24 hadoop fs -ls /