在 Debian 系统上配置 Hadoop(以 单机/伪分布式模式 为例,最常用入门方案)可以按下面步骤来。以下示例基于 Debian 11/12 + Hadoop 3.x + OpenJDK 8/11,你可以按需调整版本。
Hadoop 依赖 Java。
sudo apt update
sudo apt install openjdk-11-jdk -y
验证:
java -version
编辑环境变量:
sudo nano /etc/profile.d/java.sh
添加:
export JAVA_HOME=/usr/lib/jvm/java-11-openjdk-amd64
export PATH=$JAVA_HOME/bin:$PATH
生效:
source /etc/profile.d/java.sh
sudo adduser hadoop
sudo usermod -aG sudo hadoop
su - hadoop
到 Apache 官方镜像下载(示例为 3.3.6):
wget https://downloads.apache.org/hadoop/common/hadoop-3.3.6/hadoop-3.3.6.tar.gz
解压:
tar -xzf hadoop-3.3.6.tar.gz
mv hadoop-3.3.6 ~/hadoop
编辑 ~/.bashrc:
nano ~/.bashrc
添加:
export HADOOP_HOME=~/hadoop
export PATH=$HADOOP_HOME/bin:$HADOOP_HOME/sbin:$PATH
export HADOOP_CONF_DIR=$HADOOP_HOME/etc/hadoop
生效:
source ~/.bashrc
验证:
hadoop version
Hadoop 依赖 SSH。
sudo apt install ssh
ssh-keygen -t rsa -P "" -f ~/.ssh/id_rsa
cat ~/.ssh/id_rsa.pub >> ~/.ssh/authorized_keys
chmod 600 ~/.ssh/authorized_keys
测试:
ssh localhost
进入配置目录:
cd $HADOOP_HOME/etc/hadoop
编辑:
nano hadoop-env.sh
添加或修改:
export JAVA_HOME=/usr/lib/jvm/java-11-openjdk-amd64
nano core-site.xml
<configuration>
<property>
<name>fs.defaultFS</name>
<value>hdfs://localhost:9000</value>
</property>
</configuration>
nano hdfs-site.xml
<configuration>
<property>
<name>dfs.replication</name>
<value>1</value>
</property>
</configuration>
nano mapred-site.xml
<configuration>
<property>
<name>mapreduce.framework.name</name>
<value>yarn</value>
</property>
</configuration>
nano yarn-site.xml
<configuration>
<property>
<name>yarn.nodemanager.aux-services</name>
<value>mapreduce_shuffle</value>
</property>
</configuration>
⚠️ 只执行一次
hdfs namenode -format
start-dfs.sh
start-yarn.sh
查看进程:
jps
应看到:
hdfs dfs -mkdir /input
hdfs dfs -put $HADOOP_HOME/etc/hadoop/*.xml /input
hadoop jar $HADOOP_HOME/share/hadoop/mapreduce/hadoop-mapreduce-examples-*.jar grep /input /output 'dfs[a-z.]+'
hdfs dfs -cat /output/part-r-00000
stop-yarn.sh
stop-dfs.sh
确认 hadoop-env.sh 中已显式设置 JAVA_HOME
netstat -tunlp | grep 9000
确保 Hadoop 目录属于 hadoop 用户:
sudo chown -R hadoop:hadoop ~/hadoop
如果你需要:
可以告诉我你的具体使用场景,我可以给你定制方案。