下面以 CentOS 7/8 为例,给你一个**从零配置 HDFS(Hadoop HDFS)**的完整流程,适合单机伪分布式或集群起步。
systemctl stop firewalld
systemctl disable firewalld
setenforce 0
sed -i 's/SELINUX=enforcing/SELINUX=disabled/' /etc/selinux/config
yum install -y java-1.8.0-openjdk java-1.8.0-openjdk-devel
验证:
java -version
useradd hadoop
passwd hadoop
后续操作建议切换到该用户:
su - hadoop
cd /opt
wget https://downloads.apache.org/hadoop/common/hadoop-3.3.6/hadoop-3.3.6.tar.gz
tar -zxvf hadoop-3.3.6.tar.gz
mv hadoop-3.3.6 hadoop
编辑 ~/.bashrc:
export HADOOP_HOME=/opt/hadoop
export PATH=$PATH:$HADOOP_HOME/bin:$HADOOP_HOME/sbin
export JAVA_HOME=/usr/lib/jvm/java-1.8.0-openjdk
生效:
source ~/.bashrc
进入配置目录:
cd $HADOOP_HOME/etc/hadoop
hadoop-env.shexport JAVA_HOME=/usr/lib/jvm/java-1.8.0-openjdk
core-site.xml<configuration>
<property>
<name>fs.defaultFS</name>
<value>hdfs://localhost:9000</value>
</property>
</configuration>
若是集群,把
localhost换成namenode主机名
hdfs-site.xml<configuration>
<property>
<name>dfs.replication</name>
<value>1</value>
</property>
<property>
<name>dfs.namenode.name.dir</name>
<value>/opt/hadoop/data/namenode</value>
</property>
<property>
<name>dfs.datanode.data.dir</name>
<value>/opt/hadoop/data/datanode</value>
</property>
</configuration>
创建目录:
mkdir -p /opt/hadoop/data/namenode
mkdir -p /opt/hadoop/data/datanode
ssh-keygen -t rsa
cat ~/.ssh/id_rsa.pub >> ~/.ssh/authorized_keys
chmod 600 ~/.ssh/authorized_keys
测试:
ssh localhost
hdfs namenode -format
✅ 看到 successfully formatted 表示成功
start-dfs.sh
检查进程:
jps
应看到:
NameNode
DataNode
SecondaryNameNode
浏览器访问:
http://<centos-ip>:9870
hdfs dfs -mkdir /test
hdfs dfs -put /etc/hosts /test
hdfs dfs -ls /test
dfs.datanode.data.dir 权限netstat -tunlp | grep 9000
hostnamectl set-hostname hadoop1
并在 /etc/hosts 中配置:
127.0.0.1 hadoop1
如果你愿意,我可以: ✅ 给你 完全分布式 HDFS 配置 ✅ 给你 生产环境参数优化 ✅ 帮你 排查启动报错日志
直接把你的 CentOS 版本 + Hadoop 版本 + 报错信息 发我即可。