Hadoop集群搭建-03编译安装hadoop
Hadoop集群搭建-02安装配置Zookeeper
Hadoop集群搭建-01前期准备
HDFS是配合Hadoop使用的分布式文件系统，分为
namenode: nn1.hadoop nn2.hadoop
datanode: s1.hadoop s2.hadoop s3.hadoop
(看不明白这5台虚拟机的请看前面 01前期准备 )
解压配置文件
[hadoop@nn1 hadoop_base_op]$ ./ssh_all.sh mv /usr/local/hadoop/etc/hadoop /usr/local/hadoop/etc/hadoop_back
[hadoop@nn1 hadoop_base_op]$ ./scp_all.sh ../up/hadoop.tar.gz /tmp/
[hadoop@nn1 hadoop_base_op]$ #批量将自定义配置 压缩包解压到/usr/local/hadoop/etc/
#批量检查配置是否正确解压
[hadoop@nn1 hadoop_base_op]$ ./ssh_all.sh head /usr/local/hadoop/etc/hadoop/hadoop-env.sh
[hadoop@nn1 hadoop_base_op]$ ./ssh_root.sh chmown -R hadoop:hadoop /usr/local/hadoop/etc/hadoop
[hadoop@nn1 hadoop_base_op]$ ./ssh_root.sh chmod -R 770 /usr/local/hadoop/etc/hadoop
初始化HDFS
流程：
- 启动zookeeper
- 启动journalnode
- 启动zookeeper客户端，初始化HA的zookeeper信息
- 对nn1上的namenode进行格式化
- 启动nn1上的namenode
- 在nn2上启动同步namenode
- 启动nn2上的namenode
- 启动ZKFC
- 启动dataname
1.查看zookeeper状态
[hadoop@nn1 zk_op]$ ./zk_ssh_all.sh /usr/local/zookeeper/bin/zkServer.sh status
ssh hadoop@"nn1.hadoop" "/usr/local/zookeeper/bin/zkServer.sh status"
ZooKeeper JMX enabled by default
Using config: /usr/local/zookeeper/bin/../conf/zoo.cfg
Mode: follower
OK!
ssh hadoop@"nn2.hadoop" "/usr/local/zookeeper/bin/zkServer.sh status"
ZooKeeper JMX enabled by default
Using config: /usr/local/zookeeper/bin/../conf/zoo.cfg
Mode: leader
OK!
ssh hadoop@"s1.hadoop" "/usr/local/zookeeper/bin/zkServer.sh status"
ZooKeeper JMX enabled by default
Using config: /usr/local/zookeeper/bin/../conf/zoo.cfg
Mode: follower
OK!
看到两个follower和一个leader说明正常运行，如果没有，就用下边的命令启动
[hadoop@nn1 zk_op]$ ./zk_ssh_all.sh /usr/local/zookeeper/bin/zkServer.sh start
2.启动journalnode
这个玩意就是namenode的同步器。
#在nn1上启动journalnode
[hadoop@nn1 zk_op]$ hadoop-daemon.sh start journalnode
#在nn2上启动journalnode
[hadoop@nn1 zk_op]$ hadoop-daemon.sh start journalnode
#可以分别打开log来查看启动状态
[hadoop@nn1 zk_op]$ tail /usr/local/hadoop-2.7.3/logs/hadoop-hadoop-journalnode-nn1.hadoop.log
2019-07-22 17:15:54,164 INFO org.apache.hadoop.ipc.Server: Starting Socket Reader #1 for port 8485
2019-07-22 17:15:54,190 INFO org.apache.hadoop.ipc.Server: IPC Server Responder: starting
2019-07-22 17:15:54,191 INFO org.apache.hadoop.ipc.Server: IPC Server listener on 8485: starting
#发现IPC通信已经建立起来了，journalnode进程在8485
3.初始化HA信息(仅第一次运行，以后不需要)
[hadoop@nn1 zk_op]$ hdfs zkfc -formatZK
[hadoop@nn1 zk_op]$ /usr/local/zookeeper/bin/zkCli.sh
[zk: localhost:2181(CONNECTED) 0] ls /
[zookeeper, hadoop-ha]
[zk: localhost:2181(CONNECTED) 1] quit
Quitting...
4.对nn1上的namenode进行格式化(仅第一次运行，以后不需要)
[hadoop@nn1 zk_op]$ hadoop namenode -format
#出现下边的说明初始化成功
#19/07/22 17:23:09 INFO common.Storage: Storage directory /data/dfsname has been successfully formatted.
5.启动nn1的namenode
[hadoop@nn1 zk_op]$ hadoop-daemon.sh start namenode
[hadoop@nn1 zk_op]$ tail /usr/local/hadoop/logs/hadoop-hadoop-namenode-nn1.hadoop.log
#
#2019-07-22 17:24:57,321 INFO org.apache.hadoop.ipc.Server: IPC Server Responder: starting
#2019-07-22 17:24:57,322 INFO org.apache.hadoop.ipc.Server: IPC Server listener on 9000: starting
#2019-07-22 17:24:57,385 INFO org.apache.hadoop.hdfs.server.namenode.NameNode: NameNode RPC up at: nn1.hadoop/192.168.10.6:9000
#2019-07-22 17:24:57,385 INFO org.apache.hadoop.hdfs.server.namenode.FSNamesystem: Starting services required for standby state
#2019-07-22 17:24:57,388 INFO org.apache.hadoop.hdfs.server.namenode.ha.EditLogTailer: Will roll logs on active node at nn2.hadoop/192.168.10.7:9000 every 120 seconds.
#2019-07-22 17:24:57,394 INFO org.apache.hadoop.hdfs.server.namenode.ha.StandbyCheckpointer: Starting standby checkpoint thread...
#Checkpointing active NN at http://nn2.hadoop:50070
#Serving checkpoints at http://nn1.hadoop:50070
6.在nn2机器上同步nn1的namenode状态(仅第一次运行，以后不需要)
我们来到nn2的控制台！
###########一定要在nn2机器上运行这个！！！！############
[hadoop@nn2 ~]$ hadoop namenode -bootstrapStandby
=====================================================
About to bootstrap Standby ID nn2 from:
Nameservice ID: ns1
Other Namenode ID: nn1
Other NN's HTTP address: http://nn1.hadoop:50070
Other NN's IPC address: nn1.hadoop/192.168.10.6:9000
Namespace ID: 1728347664
Block pool ID: BP-581543280-192.168.10.6-1563787389190
Cluster ID: CID-42d2124d-9f54-4902-aa31-948fb0233943
Layout version: -63
isUpgradeFinalized: true
=====================================================
19/07/22 17:30:24 INFO common.Storage: Storage directory /data/dfsname has been successfully formatted.
7.启动nn2的namenode
还是在nn2控制台运行！！
[hadoop@nn2 ~]$ hadoop-daemon.sh start namenode
#查看log来看看有没有启动成功
[hadoop@nn2 ~]$ tail /usr/local/hadoop-2.7.3/logs/hadoop-hadoop-namenode-nn2.hadoop.log
8.启动ZKFC
这时候在nn1和nn2分别启动ZKFC，这时候两台机器的namenode，一个变成active一个变成standby！！ZKFC实现了HA高可用的自动切换！！
#############在nn1运行#################
[hadoop@nn1 zk_op]$ hadoop-daemon.sh start zkfc
#############在nn2运行####################
[hadoop@nn2 zk_op]$ hadoop-daemon.sh start zkfc
这时候在浏览器输入地址访问两台机器的hadoop界面
http://192.168.10.6:50070/dfshealth.html#tab-overview
http://192.168.10.7:50070/dfshealth.html#tab-overview
这两个有一个active有一个是standby状态。
9.启动dataname就是启动后三台机器
########首先确定slaves文件里存放了需要配置谁为datanode
[hadoop@nn1 hadoop]$ cat slaves
s1.hadoop
s2.hadoop
s3.hadoop
###########在显示为active的机器上运行##############
[hadoop@nn1 zk_op]$ hadoop-daemons.sh start datanode
10.查看硬盘容量
打开刚才hadoop网页，查看hdfs的硬盘格式化好了没有。
这里是HDFS系统为每台实体机器的硬盘默认预留了2G(可以在配置文件hdfs-site.xml里更改)，然后实际用来做hdfs的是每台机器15G，所以三台一共45G。
image
如图成功配置好HDFS。
之前写的文章在这里：
Hadoop集群搭建-03编译安装hadoop
Hadoop集群搭建-02安装配置Zookeeper
Hadoop集群搭建-01前期准备