大数据集群配置-HA（hadoop高可用）

hadoopHA配置

软件名称	软件包名
Zookeeper	zookeeper-3.4.8.tar.gz
hive	apache-hive-2.0.0-src.tar.gz
jdk	jdk-8u65-linux-x64.tar.gz
hadoop	hadoop-2.7.1.tar.gz
mysql-connector	mysql-connector-java-5.1.26-bin.jar
CentOS	CentOS 7.4(mini 英文版本)

5.配置主机名和ip

# master 
hostname master && bash
echo master > /etc/hostname
vi /etc/hostname
# slave1 
hostname slave1 && bash
echo slave1 > /etc/hostname
vi /etc/hostname
# slave2
hostname slave2 && bash
echo slave2 > /etc/hostname
vi /etc/hostname

4.配置hosts

# 查看ip
ip a
#master slave1 slave2
vi /etc/hosts
# 例如，ip不代表你本机ip，记得更换
# 三台都需要配置hosts文件

#请根据本机ip ： ip a
192.168.10.3 master
192.168.10.4 slave1
192.168.10.5 slave2

时钟同步

在/etc/sysconfig/ntpd文件添加
YS_HWLOCK=yes
在执行命令
systemctl start ntpd
#查看是否同步时间成功
date

• 如果不行的话，执行下面的命令

#master slave1 slave2 一起执行，三台机子执行间隔越小越好
date -s "20220517 11:31:01"

防火墙关闭

命令如下

#master slalve1 slave2
systemctl stop firewalld.service
systemctl disable firewalld.service

1.JAVA安装

tar -zxvf /opt/software/jdk-8u65-linux-x64.tar.gz -C /usr/local/src
mv /usr/local/src/jdk1.8.0_65 /usr/local/src/java
chown -R root:root /usr/local/src/java
vi /etc/profile

添加如下内容并截图

export JAVA_HOME=/usr/local/src/java
export PATH=$PATH:$JAVA_HOME/bin

保存退出

source /etc/profile
update-alternatives --install /usr/bin/java java /usr/local/src/java/bin/java 200
update-alternatives --set java /usr/local/src/java/bin/java

2.安装ssh

在指定目录下安装ssh服务，查看ssh进程并截图（安装包统一在“/h3cu/”)

rpm -ivh /h3cu/*.rpm

用下面的命令查看ssh服务

rpm -qa | grep ssh

出现以下结果表示安装成功：

[root@master ~]# rpm -qa | grep ssh
openssh-7.4p1-22.el7_9.x86_64
openssh-clients-7.4p1-22.el7_9.x86_64
openssh-server-7.4p1-22.el7_9.x86_64
libssh2-1.8.0-4.el7.x86_64

3.免密配置

下面四条命令需要在三台机器上都要执行，其中ssh-keygen -t rsa 是第一个执行的

ssh-keygen -t rsa 输入后三次回车

[root@master .ssh]$ ssh-keygen -t rsa
Generating public/private rsa key pair.
Enter file in which to save the key (/root/.ssh/id_rsa): 
Enter passphrase (empty for no passphrase): 
Enter same passphrase again: 
Your identification has been saved in /root/.ssh/id_rsa.
Your public key has been saved in /root/.ssh/id_rsa.pub.
The key fingerprint is:
SHA256:M0qlJuG3H2LvgI4Av1IEitpWKo5I6VGm/mi+Yy97EU8 root@master
The key's randomart image is:
+---[RSA 2048]----+
|                 |
|.                |
|o.  .   .        |
|o .=.E o         |
|oo=o* = S        |
|+*=. B o o       |
|O+o o * .        |
|+X.= . = .       |
|+*@o.  .+        |
+----[SHA256]-----+

ssh-copy-id master

[root@master ~]$ ssh-copy-id master
/usr/bin/ssh-copy-id: INFO: Source of key(s) to be installed: "/root/.ssh/id_rsa.pub"
/usr/bin/ssh-copy-id: INFO: attempting to log in with the new key(s), to filter out any that are already installed
/usr/bin/ssh-copy-id: INFO: 1 key(s) remain to be installed -- if you are prompted now it is to install the new keys
root@master's password: 

Number of key(s) added: 1

Now try logging into the machine, with:   "ssh 'master'"
and check to make sure that only the key(s) you wanted were added.

ssh-copy-id slave1

[root@master ~]$ ssh-copy-id slave1
/usr/bin/ssh-copy-id: INFO: Source of key(s) to be installed: "/root/.ssh/id_rsa.pub"
The authenticity of host 'slave1 (192.168.28.112)' can't be established.
ECDSA key fingerprint is SHA256:P0A5pFfF46dyYzSPdTMrfrOxUrLXPK7zbjO0AJggJww.
ECDSA key fingerprint is MD5:e5:fc:9b:bd:90:b6:52:09:0b:91:a8:05:94:b8:6e:c7.
Are you sure you want to continue connecting (yes/no)? yes
/usr/bin/ssh-copy-id: INFO: attempting to log in with the new key(s), to filter out any that are already installed
/usr/bin/ssh-copy-id: INFO: 1 key(s) remain to be installed -- if you are prompted now it is to install the new keys
root@slave1's password: 

Number of key(s) added: 1

Now try logging into the machine, with:   "ssh 'slave1'"
and check to make sure that only the key(s) you wanted were added.

ssh-copy-id slave2

[root@master ~]$ ssh-copy-id slave2
/usr/bin/ssh-copy-id: INFO: Source of key(s) to be installed: "/root/.ssh/id_rsa.pub"
The authenticity of host 'slave2 (192.168.28.113)' can't be established.
ECDSA key fingerprint is SHA256:P0A5pFfF46dyYzSPdTMrfrOxUrLXPK7zbjO0AJggJww.
ECDSA key fingerprint is MD5:e5:fc:9b:bd:90:b6:52:09:0b:91:a8:05:94:b8:6e:c7.
Are you sure you want to continue connecting (yes/no)? yes
/usr/bin/ssh-copy-id: INFO: attempting to log in with the new key(s), to filter out any that are already installed
/usr/bin/ssh-copy-id: INFO: 1 key(s) remain to be installed -- if you are prompted now it is to install the new keys
root@slave2's password: 

Number of key(s) added: 1

Now try logging into the machine, with:   "ssh 'slave2'"
and check to make sure that only the key(s) you wanted were added.

截取主节点登录其中一 个从节点的结果

[root@master ~]# ssh slave1
Last login: Sun May 15 11:10:28 2022 from 192.168.10.1
[root@slave1 ~]# 

master分发环境变量文件

#master
scp -r /usr/local/src/java slave1:/usr/local/src
scp -r /usr/local/src/java slave2:/usr/local/src
scp -r /etc/profile slave1:/etc/
scp -r /etc/profile slave2:/etc/

在slave1机器执行如下代码

source /etc/profile
update-alternatives --install /usr/bin/java java /usr/local/src/java/bin/java 200
update-alternatives --set java /usr/local/src/java/bin/java

在slave2机器执行如下代码

source /etc/profile
update-alternatives --install /usr/bin/java java /usr/local/src/java/bin/java 200
update-alternatives --set java /usr/local/src/java/bin/java

6.Hadoop安装及配置

Hadoop安装

tar -zxvf /opt/software/hadoop-2.7.1.tar.gz -C /usr/local/src/
cd /usr/local/src/
mv hadoop-2.7.1/ hadoop
chown -R root:root hadoop
vi /etc/profile
#添加如下内容

export HADOOP_HOME=/usr/local/src/hadoop
export HADOOP_PREFIX=$HADOOP_HOME
export HADOOP_MAPRED_HOME=$HADOOP_HOME
export HADOOP_COMMON_HOME=$HADOOP_HOME
export HADOOP_HDFS_HOME=$HADOOP_HOME
export YARN_HOME=$HADOOP_HOME
export HADOOP_COMMON_LIB_NATIVE_DIR=$HADOOP_HOME/lib/native
export HADOOP_INSTALL=$HADOOP_HOME
export HADOOP_OPTS="-Djava.library.path=$HADOOP_INSTALL/lib:$HADOOP_COMMON_LIB_NATIVE_DIR"
export PATH=$PATH:$HADOOP_HOME/bin:$HADOOP_HOME/sbin
#:wq! 保存退出

source /etc/profile

分发环境变量

#master
scp -r /etc/profile slave1:/etc/
scp -r /etc/profile slave2:/etc/

#在slave1机器执行如下代码
source /etc/profile
#在slave2机器执行如下代码
source /etc/profile

修改配置文件

#配置文件/1+X/ha配置
将给定的core-site.xml,mapred-site.xml,hdfs-site.xml,yarn-site.xml文件复制到/usr/local/src/hadoop/etc/hadoop目录下

vi /usr/local/src/hadoop/etc/hadoop/core-site.xml
	
            fs.defaultFS
            hdfs://mycluster
        
        
            hadoop.tmp.dir
            file:/usr/local/src/hadoop/tmp
        
        
            ha.zookeeper.quorum
            master:2181,slave1:2181,slave2:2181
        
        
            ha.zookeeper.session-timeout.ms
            30000
            ms
          
        
            fs.trash.interval
            1440
        
        
            hadoop.proxyuser.root.hosts
            *
	
	
	    hadoop.proxyuser.root.groups
	    *
	

mv /usr/local/src/hadoop/etc/hadoop/mapred-site.xml.template /usr/local/src/hadoop/etc/hadoop/mapred-site.xml
vi /usr/local/src/hadoop/etc/hadoop/mapred-site.xml
       
            mapreduce.framework.name
            yarn
        
        
            mapreduce.jobhistory.address
            master:10020
        
        
            mapreduce.jobhistory.webapp.address
            master:19888
	

vi /usr/local/src/hadoop/etc/hadoop/yarn-site.xml
	 
            yarn.resourcemanager.ha.enabled
            true
        
        
        
            yarn.resourcemanager.cluster-id
            yrc
        
        
        
            yarn.resourcemanager.ha.rm-ids
            rm1,rm2
        
        
        
            yarn.resourcemanager.hostname.rm1
            master
        
        
            yarn.resourcemanager.hostname.rm2
            slave1
        
        
        
            yarn.resourcemanager.zk-address
            master:2181,slave1:2181,slave2:2181
        
        
            yarn.nodemanager.aux-services
            mapreduce_shuffle
        
        
            yarn.log-aggregation-enable
            true
        
        
            yarn.log-aggregation.retain-seconds
            86400
        
        
        
            yarn.resourcemanager.recovery.enabled
            true
        
        
        
            yarn.resourcemanager.store.class
            org.apache.hadoop.yarn.server.resourcemanager.recovery.ZKRMStateStore
        

vi /usr/local/src/hadoop/etc/hadoop/hdfs-site.xml
	
            dfs.qjournal.start-segment.timeout.ms
            60000
        
        
            dfs.nameservices
            mycluster
        
        
            dfs.ha.namenodes.mycluster
            master,slave1
        
        
            dfs.namenode.rpc-address.mycluster.master
            master:8020
        
        
            dfs.namenode.rpc-address.mycluster.slave1
            slave1:8020
        
        
            dfs.namenode.http-address.mycluster.master
            master:50070
        
        
            dfs.namenode.http-address.mycluster.slave1
            slave1:50070
        
        
            dfs.namenode.shared.edits.dir
            qjournal://master:8485;slave1:8485;slave2:8485/mycluster
        
        
            dfs.client.failover.proxy.provider.mycluster
            org.apache.hadoop.hdfs.server.namenode.ha.ConfiguredFailoverProxyProvider
        
        
            dfs.ha.fencing.methods
            
                sshfence
                shell(/bin/true)
            
        
        
        dfs.permissions.enabled
        false
        
        
            dfs.support.append
            true
        
        
            dfs.ha.fencing.ssh.private-key-files
            /root/.ssh/id_rsa
        
        
            dfs.replication
            2
        
        
            dfs.namenode.name.dir
            /usr/local/src/hadoop/tmp/hdfs/nn
        
        
            dfs.datanode.data.dir
            /usr/local/src/hadoop/tmp/hdfs/dn
        
        
            dfs.journalnode.edits.dir
            /usr/local/src/hadoop/tmp/hdfs/jn
        
        
            dfs.ha.automatic-failover.enabled
            true
        
        
            dfs.webhdfs.enabled
            true
        
        
            dfs.ha.fencing.ssh.connect-timeout
            30000
        
        
            ha.failover-controller.cli-check.rpc-timeout.ms
            60000
        

修改slaves文件

vi /usr/local/src/hadoop/etc/hadoop/slaves

对此文件添加如下内容

master
slave1
slave2

修改hadoop-env.sh

vi /usr/local/src/hadoop/etc/hadoop/hadoop-env.sh

对此文件添加如下内容

export JAVA_HOME=/usr/local/src/java

创建指定目录

mkdir -p /usr/local/src/hadoop/tmp/hdfs/{nn,dn,jn}
mkdir -p /usr/local/src/hadoop/tmp/logs

分发文件

#master
scp -r /usr/local/src/hadoop slave1:/usr/local/src/
#移动到slave1机器
scp -r /usr/local/src/hadoop slave2:/usr/local/src/
#移动到slave2机器

7.zookeeper安装及配置

zookeeper安装

tar -zxvf 文件 -C 指定位置

tar -zxvf /opt/software/zookeeper-3.4.8.tar.gz -C /usr/local/src/
cd /usr/local/src/
mv zookeeper-3.4.8/ zookeeper
chown -R root:root zookeeper

vi /etc/profile

export ZOOKEEPER_HOME=/usr/local/src/zookeeper
export PATH=$PATH:$ZOOKEEPER_HOME/bin

source /etc/profile

分发环境变量

scp -r /etc/profile root@slave1:/etc/
scp -r /etc/profile root@slave2:/etc/

#在slave1机器执行如下代码
source /etc/profile

#在slave2机器执行如下代码
source /etc/profile

修改配置文件

首先进入zookeeper的配置文件目录，复制一份zookeeper的配置文件并修改

cd /usr/local/src/zookeeper/conf/
cp zoo_sample.cfg zoo.cfg 
vi zoo.cfg 

在zoo.cfg中做如下修改

#修改
dataDir=/usr/local/src/zookeeper/data
#增加
dataLogDir=/usr/local/src/zookeeper/logs
server.1=master:2888:3888
server.2=slave1:2888:3888
server.3=slave2:2888:3888

在zookeeper目录下创建data，在data目录下创建myid文件

cd /usr/local/src/zookeeper
mkdir {logs,data}
cd data/
echo 1 > myid
vi myid
1

在myid文件里只写一个1

分发文件

scp -r /usr/local/src/zookeeper/ slave1:/usr/local/src/
scp -r /usr/local/src/zookeeper/ slave2:/usr/local/src/

#在slave1机器执行如下代码
cd /usr/local/src/zookeeper/data/
vi myid
2

在myid文件里只写一个2

#在slave2机器执行如下代码
cd /usr/local/src/zookeeper/data/
vi myid
3

在myid文件里只写一个3

zookeeper的启动

分别在三台机器执行如下命令，来启动zookeeper

/usr/local/src/zookeeper/bin/zkServer.sh start

如果出现以下权限错误
JMX enabled by default
Using config: /usr/local/src/zookeeper/bin/…/conf/zoo.cfg
Starting zookeeper … /usr/local/src/zookeeper/bin/zkServer.sh:行109: ./zookeeper.out: 权限不够
STARTED
则进去zookeeper的bin目录下,用下面的命令启动

./zkServer.sh start

8.修改数据存储路径

修改 namenode、datanode、journalnode 等存放数据的公共目录为 /usr/local/hadoop/tmp；

# 根据题目自由修改value

            dfs.namenode.name.dir
            /usr/local/src/hadoop/tmp/hdfs/nn


            dfs.datanode.data.dir
            /usr/local/src/hadoop/tmp/hdfs/dn


            dfs.journalnode.edits.dir
            /usr/local/src/hadoop/tmp/hdfs/jn

9.HA的格式化以及各节点的启动

初始化数据以及效果

初始化元数据前保证三台都处于hadoop用户下，并保证zookeeper服务正常启动

启动journalnode守护进程

执行如下命令

hadoop-daemons.sh start journalnode

​ 执行后会出现如下效果以及增加一个JournalNode进程
​ [root@master hadoop]$ hadoop-daemons.sh start journalnode
​ WARNING: Use of this script to start HDFS daemons is deprecated.
​ WARNING: Attempting to execute replacement “hdfs --workers --daemon start” instead.
​ [root@master hadoop]$ jps
​ 4944 Jps
​ 3273 QuorumPeerMain
​ 4895 JournalNode

初始化namenode

执行如下命令

hdfs namenode -format

​ 部分效果如下所示
​ 2022-05-13 22:17:03,436 INFO namenode.FSImage: Allocated new BlockPoolId: BP-683251328-192.168.28.111-1652451423436
​ 2022-05-13 22:17:03,447 INFO common.Storage: Storage directory /usr/local/src/hadoop/tmp/hdfs/nn has been successfully formatted.
​ 2022-05-13 22:17:03,541 INFO namenode.FSImageFormatProtobuf: Saving image file /usr/local/src/hadoop/tmp/hdfs/nn/current/fsimage.ckpt_0000000000000000000 using no compression
​ 2022-05-13 22:17:03,788 INFO namenode.FSImageFormatProtobuf: Image file /usr/local/src/hadoop/tmp/hdfs/nn/current/fsimage.ckpt_0000000000000000000 of size 390 bytes saved in 0 seconds .
​ 2022-05-13 22:17:03,791 INFO namenode.NNStorageRetentionManager: Going to retain 1 images with txid >= 0
​ 2022-05-13 22:17:03,819 INFO namenode.FSImage: FSImageSaver clean checkpoint: txid = 0 when meet shutdown.
​ 2022-05-13 22:17:03,819 INFO namenode.NameNode: SHUTDOWN_MSG:
​ /************************************************************
​ SHUTDOWN_MSG: Shutting down NameNode at master/192.168.28.111
​ ************************************************************/

注册ZNode

执行如下命令

hdfs zkfc -formatZK

​ 部分效果如下所示
​ 2022-05-13 22:19:22,621 INFO zookeeper.ZooKeeper: Client environment:java.library.path=/usr/local/src/hadoop/lib/native
​ 2022-05-13 22:19:22,621 INFO zookeeper.ZooKeeper: Client environment:java.io.tmpdir=/tmp
​ 2022-05-13 22:19:22,621 INFO zookeeper.ZooKeeper: Client environment:java.compiler=
​ 2022-05-13 22:19:22,621 INFO zookeeper.ZooKeeper: Client environment:os.name=Linux
​ 2022-05-13 22:19:22,621 INFO zookeeper.ZooKeeper: Client environment:os.arch=amd64
​ 2022-05-13 22:19:22,621 INFO zookeeper.ZooKeeper: Client environment:os.version=3.10.0-862.el7.x86_64
​ 2022-05-13 22:19:22,621 INFO zookeeper.ZooKeeper: Client environment:user.name=hadoop
​ 2022-05-13 22:19:22,621 INFO zookeeper.ZooKeeper: Client environment:user.home=/root
​ 2022-05-13 22:19:22,621 INFO zookeeper.ZooKeeper: Client environment:user.dir=/usr/local/src/hadoop/etc/hadoop
​ 2022-05-13 22:19:22,621 INFO zookeeper.ZooKeeper: Initiating client connection, connectString=master:2181,slave1:2181,slave2:2181 sessionTimeout=30000 watcher=org.apache.hadoop.ha.ActiveStandbyElector$WatcherWithClientRef@32eff8762022-05-1322:19:22,633INFOzookeeper.ClientCnxn:Openingsocketconnectiontoserverslave2/192.168.28.113:2181.WillnotattempttoauthenticateusingSASL(unknownerror)2022-05-1322:19:22,636INFOzookeeper.ClientCnxn:Socketconnectionestablishedtoslave2/192.168.28.113:2181,initiatingsession2022-05-1322:19:22,659INFOzookeeper.ClientCnxn:Sessionestablishmentcompleteonserverslave2/192.168.28.113:2181,sessionid=0xff80bd967d0b0000,negotiatedtimeout=300002022-05-1322:19:22,660INFOha.ActiveStandbyElector:Sessionconnected.2022-05-1322:19:22,683INFOha.ActiveStandbyElector:Successfullycreated/hadoop-ha/myclusterinZK.2022-05-1322:19:22,687INFOzookeeper.ZooKeeper:Session:0xff80bd967d0b0000closed2022-05-1322:19:22,689INFOzookeeper.ClientCnxn:EventThreadshutdownforsession:0xff80bd967d0b00002022-05-1322:19:22,690INFOtools.DFSZKFailoverController:SHUTDOW{N}_{M}SG:/\ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast SHUTDOW{N}_{M}SG:ShuttingdownDFSZKFailoverControlleratmaster/192.168.28.111\ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast \ast /[root@masterhadoop]$

10.启动hadoop

start-dfs.sh
start-yarn.sh

start-dfs.sh

    [root@master hadoop]$ jps
    3273 QuorumPeerMain
    7099 Jps
    [root@master hadoop]$ start-dfs.sh 
    Starting namenodes on [master slave1]
    Starting datanodes
    Starting journal nodes [slave2 slave1 master]
    Starting ZK Failover Controllers on NN hosts [master slave1]
    [root@master hadoop]$ jps
    7664 JournalNode
    7285 NameNode
    3273 QuorumPeerMain
    7961 Jps
    7419 DataNode
    7886 DFSZKFailoverController

[root@slave1 hadoop]$ jps
5330 DataNode
2964 QuorumPeerMain
5556 DFSZKFailoverController
5604 Jps
5445 JournalNode

[root@slave2 hadoop]$ jps
5042 JournalNode
5106 Jps
3108 QuorumPeerMain
4926 DataNode

start-yarn.sh

[root@master hadoop]$ start-yarn.sh 
Starting resourcemanagers on [ master slave1]
Starting nodemanagers
[root@master hadoop]$ jps
9667 JournalNode
9284 NameNode
10292 ResourceManager
10774 Jps
10440 NodeManager
3273 QuorumPeerMain
9900 DFSZKFailoverController
9421 DataNode

[root@slave1 hadoop]$ jps
6560 ResourceManager
6209 DataNode
6657 NodeManager
6323 JournalNode
2964 QuorumPeerMain
6442 DFSZKFailoverController
6783 Jps

[root@slave2 hadoop]$ jps
3108 QuorumPeerMain
5556 JournalNode
5812 Jps
5705 NodeManager
5438 DataNode

启动 MapReduce任务历史服务器

yarn-daemon.sh start proxyserver
mr-jobhistory-daemon.sh start historyserver

​ 效果如下

    [root@master ~]$ yarn-daemon.sh start proxyserver
    WARNING: Use of this script to start YARN daemons is deprecated.
    WARNING: Attempting to execute replacement "yarn --daemon start" instead.
    效果如下
    [root@master ~]$ mr-jobhistory-daemon.sh start historyserver
    WARNING: Use of this script to start the MR JobHistory daemon is deprecated.
    WARNING: Attempting to execute replacement "mapred --daemon start" instead.

12.格式化主从节点

本题就是将master的namenode的元数据发送到slave1和slave2机器上

scp -r /usr/local/src/hadoop/tmp/* slave1:/usr/local/src/hadoop/tmp/
scp -r /usr/local/src/hadoop/tmp/* slave2:/usr/local/src/hadoop/tmp/

13.启动两个 namenode 和 resourcemanager

在三台机器jps查看的结果在只有master上有一个namenode,这就需要去slave1机器上单点去启动namenode

#slave1 
hadoop-daemon.sh start namenode
yarn-daemon.sh start resourcemanager

检查下resourcemanager进程在master和slave1都存在，所以不需要单独启动，如有缺失，执行如下代码

14.查看

# master slave1 slave2
jps
#访问两个namenode 和 resourcemanager web 界面
master:50070
master:8088
slave1:50070
slave1:8088

使用内置游览器访问master:50070和slave1:50070查看状态并截图
访问master:8088页面并在左侧选项栏中点击nodes后截图

15.终止 active 的 namenode 进程

在master机器执行如下代码终止active的namenode进程

hadoop-daemon.sh stop namenode

​ 效果如下

[root@master hadoop]# hadoop-daemon.sh stop namenode
stopping namenode

# master slave1 slave2
jps
#访问两个namenode 和 resourcemanager web 界面
master:50070
master:8088
slave1:50070
slave1:8088

16.重启master的namenode服务

#master
hadoop-daemon.sh start namenode

• 查看master和slave1的状态,active表示运行,standby表示准备替代

hdfs haadmin -getServiceState master
hdfs haadmin -getServiceState slave
#测试
hadoop jar ./share/hadoop/mapreduce/hadoop-mapreduce-examples-3.3.1.jar pi 10 10
hadoop jar ./share/hadoop/mapreduce/hadoop-mapreduce-examples-3.3.1.jar wordcount /wordcount/input/1.txt /wordcount/output/1