Hadoop集群搭建（三个节点）--摘要

前置准备：

1、修改主机名，永久生效（不同版本方式不同）

centos6修改hostname

[root@centos6 ~]$ hostname                                             	# 查看当前的hostnmae
node1
[root@centos6 ~]$ vim /etc/sysconfig/network                            # 编辑network文件修改hostname行（重启生效）
[root@centos6 ~]$ cat /etc/sysconfig/network                            # 检查修改
NETWORKING=yes
HOSTNAME=centos6-node1

[root@centos6 ~]$ hostname centos6-node1                         		# 设置当前的hostname(立即生效）
[root@centos6 ~]$ vim /etc/hosts                                        # 编辑hosts文件，给127.0.0.1添加hostname
[root@centos6 ~]$ cat /etc/hosts                                        # 检查
127.0.0.1 localhost localhost.localdomain localhost4 localhost4.localdomain4
::1 localhost localhost.localdomain localhost6 localhost6.localdomain6 centos6-node1

centos7修改hostname

[root@centos7 ~]$ hostname                                              # 查看
node1
[root@centos7 ~]$ hostnamectl set-hostname centos7-node1             	# 使用这个命令会立即生效且重启也生效
[root@centos7 ~]$ hostname                                              # 再次查看
centos7-node1
[root@centos7 ~]$ vim /etc/hosts                                        # 编辑下hosts文件， 给127.0.0.1添加hostname
[root@centos7 ~]$ cat /etc/hosts                                        # 检查
127.0.0.1   localhost localhost.localdomain localhost4 localhost4.localdomain4
::1         localhost localhost.localdomain localhost6 localhost6.localdomain6 centos7-node1

2、配置映射

这里的映射就和Windows下的原理一样(C:\Windows\System32\drivers\etc\hosts)

[root@master ~]$ sudo vim /etc/hosts

在文件尾部追加以下内容：

192.168.0.104 master
192.168.0.102 slave1
192.168.0.106 slave2

3、关闭防火墙

# 查看防火墙状态：
service firewalld status

#关闭防火墙：
sudo systemctl stop firewalld

#关闭防火墙开机自启：
sudo systemctl disable firewalld.service

# 查看防火墙状态：
[root@master software]# service firewalld status
Redirecting to /bin/systemctl status firewalld.service
● firewalld.service - firewalld - dynamic firewall daemon
   Loaded: loaded (/usr/lib/systemd/system/firewalld.service; enabled; vendor preset: enabled)
   Active: active (running) since 一 2020-07-13 17:34:12 CST; 11min ago
     Docs: man:firewalld(1)
 Main PID: 562 (firewalld)
   CGroup: /system.slice/firewalld.service
           └─562 /usr/bin/python2 -Es /usr/sbin/firewalld --nofork --nopid

7月 13 17:34:11 master systemd[1]: Starting firewalld - dynamic firewall daemon...
7月 13 17:34:12 master systemd[1]: Started firewalld - dynamic firewall daemon.

#关闭防火墙：
[root@master software]# systemctl stop firewalld

#关闭防火墙开机自启：
[root@master software]# systemctl disable firewalld.service
Removed symlink /etc/systemd/system/multi-user.target.wants/firewalld.service.
Removed symlink /etc/systemd/system/dbus-org.fedoraproject.FirewallD1.service.

# 查看防火墙状态：
[root@master software]# service firewalld status
Redirecting to /bin/systemctl status firewalld.service
● firewalld.service - firewalld - dynamic firewall daemon
   Loaded: loaded (/usr/lib/systemd/system/firewalld.service; disabled; vendor preset: enabled)
   Active: inactive (dead)
     Docs: man:firewalld(1)

7月 13 17:34:11 master systemd[1]: Starting firewalld - dynamic firewall daemon...
7月 13 17:34:12 master systemd[1]: Started firewalld - dynamic firewall daemon.
7月 13 17:46:23 master systemd[1]: Stopping firewalld - dynamic firewall daemon...
7月 13 17:46:23 master systemd[1]: Stopped firewalld - dynamic firewall daemon.

4、配置SSH（自己免密登录自己和两台slave）

检查是否已经安装了ssh：

[root@master software]# rpm -qa | grep ssh
openssh-server-7.4p1-21.el7.x86_64
openssh-clients-7.4p1-21.el7.x86_64
libssh2-1.8.0-3.el7.x86_64
openssh-7.4p1-21.el7.x86_64

没有安装的话执行以下命令：

[root@master software]$ sudo yum -y install ssh

查看ssh服务状态：`

[root@master software]# service sshd status
Redirecting to /bin/systemctl status sshd.service
● sshd.service - OpenSSH server daemon
   Loaded: loaded (/usr/lib/systemd/system/sshd.service; enabled; vendor preset: enabled)
   Active: active (running) since 一 2020-07-13 17:34:14 CST; 18min ago
     Docs: man:sshd(8)
           man:sshd_config(5)
 Main PID: 914 (sshd)
   CGroup: /system.slice/sshd.service
           └─914 /usr/sbin/sshd -D

7月 13 17:34:13 master systemd[1]: Starting OpenSSH server daemon...
7月 13 17:34:14 master sshd[914]: Server listening on 0.0.0.0 port 22.
7月 13 17:34:14 master sshd[914]: Server listening on :: port 22.
7月 13 17:34:14 master systemd[1]: Started OpenSSH server daemon.
7月 13 17:44:25 master sshd[1448]: Accepted password for root from 192.168.0.101 port 50808 ssh2
[root@master software]# 

ssh-keygen是SSH服务下的一个生成、管理和转换认证密钥的命令工具。包括两种密钥类型DSA和RSA
通过公私钥的验证可以使服务器与服务器之间实现无密码通讯。
ssh-keygen常用参数
-t：指定生成密钥的类型，默认使用SSH2d的rsa
-f：指定生成密钥的文件名，默认id_rsa（私钥id_rsa，公钥id_rsa.pub）
-P：提供旧密码，空表示不需要密码（-P ‘’）
-N：提供新密码，空表示不需要密码(-N ‘’)
-b：指定密钥长度（bits），RSA最小要求768位，默认是2048位；DSA密钥必须是1024位（FIPS 1862标准规定）
-C：提供一个新注释
-R hostname：从known_hosta（第一次连接时就会在家目录.ssh目录下生产该密钥文件）文件中删除所有属于hostname的密钥

生成公钥和私钥：

[root@master software]# ssh-keygen
#三次回车

[root@master software]# ssh-keygen
Generating public/private rsa key pair.
Enter file in which to save the key (/root/.ssh/id_rsa): 
Created directory '/root/.ssh'.
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:
SHA256:0kJRHiY4Et0j0iHX19P55Gf7OPxbOfUnFh/w3/ty5oY root@master
The key's randomart image is:
+---[RSA 2048]----+
|  o+o=o.+. . .   |
|  oo* +=..o o .  |
|   o o.o.  . =   |
|     . .      = o|
|      o S     .=o|
|       o       +B|
|             .o=O|
|             .E.X|
|               @*|
+----[SHA256]-----+
[root@master software]# 

将公钥复制到需要免密登陆的主机上的authorized_keys上：

[root@master software]# scp /root/.ssh/id_rsa.pub slave1:/root/.ssh/authorized_keys 

# 派发到slave1
[root@master software]# scp /root/.ssh/id_rsa.pub slave1:/root/.ssh/authorized_keys 
The authenticity of host 'slave1 (192.168.0.102)' can't be established.
ECDSA key fingerprint is SHA256:GuWVSxRlZdj2Da8PAZg0AnYTN9TSPt8bv82ApaQjyfU.
ECDSA key fingerprint is MD5:db:26:91:1f:00:30:7c:cc:a6:10:05:de:46:21:58:0e.
Are you sure you want to continue connecting (yes/no)? yes
Warning: Permanently added 'slave1,192.168.0.102' (ECDSA) to the list of known hosts.
root@slave1's password: 
id_rsa.pub                                                               100%  393   594.5KB/s   00:00    

[2]+  已停止               scp /root/.ssh/id_rsa.pub slave1:/root/.ssh/authorized_keys
[root@master software]# 

# 派发到slave2
[root@master software]# scp /root/.ssh/id_rsa.pub slave2:/root/.ssh/authorized_keys 
The authenticity of host 'slave2 (192.168.0.106)' can't be established.
ECDSA key fingerprint is SHA256:GuWVSxRlZdj2Da8PAZg0AnYTN9TSPt8bv82ApaQjyfU.
ECDSA key fingerprint is MD5:db:26:91:1f:00:30:7c:cc:a6:10:05:de:46:21:58:0e.
Are you sure you want to continue connecting (yes/no)? yes
Warning: Permanently added 'slave2,192.168.0.106' (ECDSA) to the list of known hosts.
root@slave2's password: 
id_rsa.pub                                                               100%  393   462.5KB/s   00:00    
[root@master software]# ssh slave2
Last login: Mon Jul 13 17:44:55 2020 from 192.168.0.101
[root@slave2 ~]# exit
登出
Connection to slave2 closed.
[root@master software]# 

测试是否能免密登录：

[root@master software]# ssh slave1
Last login: Mon Jul 13 17:44:40 2020 from 192.168.0.101
[root@slave1 ~]# exit
登出
Connection to slave1 closed.
[root@master software]# 

[root@master software]# ssh slave2
Last login: Mon Jul 13 17:44:40 2020 from 192.168.0.101
[root@slave1 ~]# exit
登出
Connection to slave1 closed.
[root@master software]# 

5、配置时间服务器（master）

1. 检查ntp包是否安装

[root@master software]# rpm -qa | grep ntp
ntpdate-4.2.6p5-29.el7.centos.x86_64
ntp-4.2.6p5-29.el7.centos.x86_64

没有安装的话，执行以下命令进行安装：

[root@master software]# yum -y install ntp

2. 设置时间配置文件

[root@master software]# vim /etc/ntp.conf
#设置本地网络上的主机不受限制
#restrict 192.168.1.0 mask 255.255.255.0 nomodify notrap 为
restrict 192.168.239.0 mask 255.255.255.0 nomodify notrap

#在includefile上面添加默认的一个内部时钟数据，使用它为局域网用户提供服务
server 127.127.1.0
fudge 127.127.1.0 stratum 10
includefile /etc/ntp/crypto/pw

#设置为不采用公共的服务器
server 0.centos.pool.ntp.org iburst
server 1.centos.pool.ntp.org iburst
server 2.centos.pool.ntp.org iburst
server 3.centos.pool.ntp.org iburst 

# Use public servers from the pool.ntp.org project.
# Please consider joining the pool (http://www.pool.ntp.org/join.html).
# server 0.centos.pool.ntp.org iburst
# server 1.centos.pool.ntp.org iburst
# server 2.centos.pool.ntp.org iburst
# server 3.centos.pool.ntp.org iburst

3. 设置BIOS与系统时间同步

[root@master software]# vim /etc/sysconfig/ntpd
#增加如下内容（让硬件时间与系统时间一起同步）
OPTIONS="-u ntp:ntp -p /var/run/ntpd.pid -g"
SYNC_HWCLOCK=yes

4. 启动ntp服务并测试

[root@master software]# systemctl start ntpd
[root@master software]# systemctl status ntpd
[root@master hadoop]# systemctl status ntpd
● ntpd.service - Network Time Service
   Loaded: loaded (/usr/lib/systemd/system/ntpd.service; enabled; vendor preset: disabled)
   Active: active (running) since 一 2020-07-13 21:11:24 CST; 24s ago
  Process: 3982 ExecStart=/usr/sbin/ntpd -u ntp:ntp $OPTIONS (code=exited, status=0/SUCCESS)
 Main PID: 3983 (ntpd)
   CGroup: /system.slice/ntpd.service
           └─3983 /usr/sbin/ntpd -u ntp:ntp -g

7月 13 21:11:24 master ntpd[3983]: Listen and drop on 1 v6wildcard :: UDP 123
7月 13 21:11:24 master ntpd[3983]: Listen normally on 2 lo 127.0.0.1 UDP 123
7月 13 21:11:24 master ntpd[3983]: Listen normally on 3 ens33 192.168.0.104 UDP 123
7月 13 21:11:24 master ntpd[3983]: Listen normally on 4 lo ::1 UDP 123
7月 13 21:11:24 master ntpd[3983]: Listen normally on 5 ens33 fe80::5206:bab2:53a:9a51 UDP 123
7月 13 21:11:24 master ntpd[3983]: Listening on routing socket on fd #22 for interface updates
7月 13 21:11:24 master ntpd[3983]: 0.0.0.0 c016 06 restart
7月 13 21:11:24 master ntpd[3983]: 0.0.0.0 c012 02 freq_set kernel 0.000 PPM
7月 13 21:11:24 master ntpd[3983]: 0.0.0.0 c011 01 freq_not_set
7月 13 21:11:25 master ntpd[3983]: 0.0.0.0 c514 04 freq_mode
[root@master hadoop]# 


#设置ntp服务开机自启
[root@master Hadoop]# systemctl enable ntpd.service

#测试
[root@master hadoop]# ntpstat
synchronised to local net (127.127.1.0) at stratum 11
   time correct to within 949 ms
   polling server every 64 s
[root@master hadoop]# 

5. 其它节点与时间服务器同步时间

先关闭非时间服务器节点的ntpd服务

[root@slave1 hadoop]# systemctl stop ntpd

1. 手动同步

[root@slave1 software]# ntpdate master
13 Jul 21:18:21 ntpdate[2201]: adjust time server 192.168.0.104 offset -0.008088 sec
[root@slave1 software]# date
2020年 07月 13日 星期一 21:18:52 CST

2. 定时同步

在其他机器配置10分钟与时间服务器同步一次

[root@slave1 software]# crontab -e
no crontab for root - using an empty one
crontab: installing new crontab

JDK安装

系统环境：centos 7

JDK 版本：jdk 1.8.0_191

（1）准备软件

JDK的安装包已经为大家准备好，在/root/software目录下。

（2）解压压缩包

tar -zxvf jdk-8u171-linux-x64.tar.gz

（3）在此处我们配置系统环境变量，使用命令：

vim /etc/profile

（4）在最后加入以下两行内容：

export JAVA_HOME=/root/software/jdk1.8.0_221  # 配置Java的安装目录
export PATH=$PATH:$JAVA_HOME/bin  # 在原PATH的基础上加入JDK的bin目录

（5）让配置文件立即生效，使用如下命令：

source /etc/profile

（6）检测JDK是否安装成功，使用命令查看JDK版本：

java -version

[root@master software]# java -version
java version "1.8.0_171"
Java(TM) SE Runtime Environment (build 1.8.0_171-b11)
Java HotSpot(TM) 64-Bit Server VM (build 25.171-b11, mixed mode)
[root@master software]# 

Hadoop安装

1. 解压hadoop2.7.7安装包

使用cd命令进入/root/software目录下，使用如下命令解压hadoop2.7.7安装包：

tar -zxvf hadoop-2.7.7.tar.gz

2. 配置Hadoop系统环境变量

(1) 首先打开/etc/profile文件（系统环境变量：对所有用户有效）：

vim /etc/profile

(2) 在文件底部添加如下内容：

# 配置Hadoop的安装目录
export HADOOP_HOME=/root/software/hadoop-2.7.7
# 在原PATH的基础上加入Hadoop的bin和sbin目录
export PATH=$PATH:$HADOOP_HOME/bin
export PATH=$PATH:$HADOOP_HOME/sbin

(3) 让配置文件立即生效，使用如下命令：

source /etc/profile

(4) 检测Hadoop环境变量是否设置成功，使用如下命令查看Hadoop版本：

hadoop version

[root@master software]# vi /etc/profile
[root@master software]# source /etc/profile
[root@master software]# hadoop version
Hadoop 2.7.7
Subversion Unknown -r c1aad84bd27cd79c3d1a7dd58202a8c3ee1ed3ac
Compiled by stevel on 2018-07-18T22:47Z
Compiled with protoc 2.5.0
From source with checksum 792e15d20b12c74bd6f19a1fb886490
This command was run using /root/software/hadoop-2.7.7/share/hadoop/common/hadoop-common-2.7.7.jar
[root@master software]# 

3. 配置hdfs环境变量hadoop-env.sh

打开hadoop-env.sh文件：

[root@master software]# vi /root/software/hadoop-2.7.7/etc/hadoop/hadoop-env.sh

找到JAVA_HOME参数位置，修改为本机安装的JDK的实际位置。

[root@master software]# echo $JAVA_HOME
/root/software/jdk1.8.0_171
[root@master software]# vi /root/software/hadoop-2.7.7/etc/hadoop/hadoop-env.sh

3. 配置核心组件core-site.xml

使用如下命令打开“core-site.xml”文件：

vi /root/software/hadoop-2.7.7/etc/hadoop/core-site.xml

将下面的配置内容添加到 中间：

<configuration>

        
        <property>
                <name>fs.defaultFSname>
                
                <value>hdfs://master:9000value>
        property>

        
        <property>
                <name>hadoop.tmp.dirname>
                <value>/root/software/hadoop-2.7.7/tempvalue>
        property>

configuration>

4. 配置文件系统hdfs-site.xml

使用如下命令打开“hdfs-site.xml”文件：

vim /root/software/hadoop-2.7.7/etc/hadoop/hdfs-site.xml

具体配置：

<configuration>
        
        
        <property>
                <name>dfs.namenode.name.dirname>                
            	<value>/root/software/hadoop-2.7.7/dfs/namenode_datavalue>
        property>

        
        <property>
                <name>dfs.datanode.data.dirname>
                <value>/root/software/hadoop-2.7.7/dfs/datanode_datavalue>
        property>

        
        <property>
                <name>dfs.replicationname>
                <value>1value>
        property>

configuration>

5、配置环境变量yarn-env.sh

使用如下命令打开“yarn-env.sh”文件：

vi /root/software/hadoop-2.7.7/etc/hadoop/yarn-env.sh

找到JAVA_HOME参数位置，将前面的#去掉，将其值修改为本机安装的JDK的实际位置。

# some Java parameters
export JAVA_HOME=/root/software/jdk1.8.0_171

6、 配置计算框架mapred-site.xml

在$HADOOP_HOME/etc/hadoop/目录中默认没有该文件，需要先通过如下命令将文件复制并重命名为“mapred-site.xml”：

cp mapred-site.xml.template mapred-site.xml

接着，打开“mapred-site.xml”文件进行修改：

vi /root/software/hadoop-2.7.7/etc/hadoop/mapred-site.xml

具体配置：

<configuration>

        
        <property>
                <name>mapreduce.framework.namename>
                <value>yarnvalue>
        property>

configuration>

7、配置YARN系统yarn-site.xml

使用如下命令打开该配置文件：

vim /root/software/hadoop-2.7.7/etc/hadoop/yarn-site.xml

具体配置：

<configuration>

        
        <property>
                <name>yarn.nodemanager.aux-servicesname>
                <value>mapreduce_shufflevalue>
        property>

    	
    	<property>
            <name>yarn.resourcemanager.hostnamename>
            <value>mastervalue>
    	property>
    
configuration>

8. master文件

在当前配置文件目录内是不存在master文件的，我们使用vim写入内容到master内保存即可

[root@master hadoop]# vi maste

master

9. slaves文件

配置所有从属节点的主机名或 IP 地址，每行一个。所有从属节点上的 DataNode 服务和 NodeManager 服务都会被启动。

[root@master hadoop]# vi slaves

master
slave1
slave2

10、分发程序

将 Hadoop 安装包分发到其他两台服务器，分发后建议在这两台服务器上也配置一下 Hadoop 的环境变量。

# 将安装包分发到slave1
[root@master hadoop]# scp -r /root/software/hadoop-2.7.7 slave1:/root/software/
# 将安装包分发到slave2
[root@master hadoop]# scp -r /root/software/hadoop-2.7.7 slave2:/root/software/

将 jdk 安装包分发到其他两台服务器，分发后建议在这两台服务器上也配置一下 jdk 的环境变量。

# 将安装包分发到slave1
[root@master hadoop]# scp -r /root/software/jdk1.8.0_171 slave1:/root/software/
# 将安装包分发到slave2
[root@master hadoop]# scp -r /root/software/jdk1.8.0_171 slave2:/root/software/

环境变量：

export JAVA_HOME=/root/software/jdk1.8.0_171  # 配置Java的安装目录
export PATH=$PATH:$JAVA_HOME/bin  # 在原PATH的基础上加入JDK的bin目录

# 配置Hadoop的安装目录
export HADOOP_HOME=/root/software/hadoop-2.7.7
# 在原PATH的基础上加入Hadoop的bin和sbin目录
export PATH=$PATH:$HADOOP_HOME/bin
export PATH=$PATH:$HADOOP_HOME/sbin

11、DHFS文件系统初始化

[root@master software]# hdfs namenode -format

成功标志：

namenode_data has been successfully formatted.

20/07/13 19:25:46 INFO namenode.NNStorageRetentionManager: Going to retain 1 images with txid >= 0

20/07/13 19:25:46 INFO common.Storage: Storage directory /root/software/hadoop-2.7.7/dfs/namenode_data has been successfully formatted.
20/07/13 19:25:46 INFO namenode.FSImageFormatProtobuf: Saving image file /root/software/hadoop-2.7.7/dfs/namenode_data/current/fsimage.ckpt_0000000000000000000 using no compression
20/07/13 19:25:46 INFO namenode.FSImageFormatProtobuf: Image file /root/software/hadoop-2.7.7/dfs/namenode_data/current/fsimage.ckpt_0000000000000000000 of size 321 bytes saved in 0 seconds.
20/07/13 19:25:46 INFO namenode.NNStorageRetentionManager: Going to retain 1 images with txid >= 0
20/07/13 19:25:46 INFO util.ExitUtil: Exiting with status 0
20/07/13 19:25:46 INFO namenode.NameNode: SHUTDOWN_MSG: 
/************************************************************
SHUTDOWN_MSG: Shutting down NameNode at master/192.168.0.104
************************************************************/

12、启动集群：

# 启动dfs服务
[xiaokang@hadoop01 ~]$ start-dfs.sh
# 启动yarn服务
[xiaokang@hadoop01 ~]$ start-yarn.sh
# 启动任务历史服务器
[xiaokang@hadoop01 ~]$ mr-jobhistory-daemon.sh start historyserver

Master：

DFS：

[root@master .ssh]# start-dfs.sh
Starting namenodes on [master]
master: starting namenode, logging to /root/software/hadoop-2.7.7/logs/hadoop-root-namenode-master.out
slave2: starting datanode, logging to /root/software/hadoop-2.7.7/logs/hadoop-root-datanode-slave2.out
master: starting datanode, logging to /root/software/hadoop-2.7.7/logs/hadoop-root-datanode-master.out
slave1: starting datanode, logging to /root/software/hadoop-2.7.7/logs/hadoop-root-datanode-slave1.out
Starting secondary namenodes [0.0.0.0]
0.0.0.0: starting secondarynamenode, logging to /root/software/hadoop-2.7.7/logs/hadoop-root-secondarynamenode-master.out
[root@master .ssh]# jps
3156 Jps
3047 SecondaryNameNode
2889 DataNode
2762 NameNode
[root@master .ssh]# 

YARN：

[root@master .ssh]# start-yarn.sh
starting yarn daemons
starting resourcemanager, logging to /root/software/hadoop-2.7.7/logs/yarn-root-resourcemanager-master.out
slave2: starting nodemanager, logging to /root/software/hadoop-2.7.7/logs/yarn-root-nodemanager-slave2.out
slave1: starting nodemanager, logging to /root/software/hadoop-2.7.7/logs/yarn-root-nodemanager-slave1.out
master: starting nodemanager, logging to /root/software/hadoop-2.7.7/logs/yarn-root-nodemanager-master.out
[root@master .ssh]# jps
3203 ResourceManager
3047 SecondaryNameNode
3367 NodeManager
2889 DataNode
3545 Jps
2762 NameNode
[root@master .ssh]# 

Slave1：

[root@slave1 software]# jps
2064 Jps
1864 DataNode
1964 NodeManager
[root@slave1 software]# 

Slave2：

[root@slave2 software]# jps
2067 Jps
1869 DataNode
1967 NodeManager
[root@slave2 software]# 

13、进入 Web-UI 界面进行查看

安装好hadoop，hadoop和yarn都正常启动，但是yarn的web界面（8088），hdfs的web界面（50070）都不能打开，防火墙是处于关闭状态。

解决方法：

执行命令：

netstat -nltp

没安装net-tools会报错

[root@master hadoop]# netstat -nltp
-bash: netstat: 未找到命令

再执行命令：

# yum -y install net-tools

[root@master hadoop]# yum -y install net-tools
已加载插件：fastestmirror
Loading mirror speeds from cached hostfile
 * base: mirrors.aliyun.com
 * extras: mirrors.163.com
 * updates: mirrors.aliyun.com
正在解决依赖关系
--> 正在检查事务
---> 软件包 net-tools.x86_64.0.2.0-0.25.20131004git.el7 将被 安装
--> 解决依赖关系完成

依赖关系解决

===========================================================================================================
 Package                架构                版本                                   源                 大小
===========================================================================================================
正在安装:
 net-tools              x86_64              2.0-0.25.20131004git.el7               base              306 k

事务概要
===========================================================================================================
安装  1 软件包

总下载量：306 k
安装大小：917 k
Downloading packages:
net-tools-2.0-0.25.20131004git.el7.x86_64.rpm                                       | 306 kB  00:00:00     
Running transaction check
Running transaction test
Transaction test succeeded
Running transaction
  正在安装    : net-tools-2.0-0.25.20131004git.el7.x86_64                                              1/1 
  验证中      : net-tools-2.0-0.25.20131004git.el7.x86_64                                              1/1 

已安装:
  net-tools.x86_64 0:2.0-0.25.20131004git.el7                                                              

完毕！

再次执行：

netstat -nltp

查看端口状态：

[root@master hadoop]# netstat -nltp
Active Internet connections (only servers)
Proto Recv-Q Send-Q Local Address           Foreign Address         State       PID/Program name    
tcp        0      0 0.0.0.0:50020           0.0.0.0:*               LISTEN      2889/java           
tcp        0      0 192.168.0.104:9000      0.0.0.0:*               LISTEN      2762/java           
tcp        0      0 0.0.0.0:50090           0.0.0.0:*               LISTEN      3047/java           
tcp        0      0 127.0.0.1:42319         0.0.0.0:*               LISTEN      2889/java           
tcp        0      0 0.0.0.0:50070           0.0.0.0:*               LISTEN      2762/java           
tcp        0      0 0.0.0.0:22              0.0.0.0:*               LISTEN      914/sshd            
tcp        0      0 127.0.0.1:25            0.0.0.0:*               LISTEN      1164/master         
tcp        0      0 0.0.0.0:50010           0.0.0.0:*               LISTEN      2889/java           
tcp        0      0 0.0.0.0:50075           0.0.0.0:*               LISTEN      2889/java           
tcp6       0      0 :::42140                :::*                    LISTEN      3367/java           
tcp6       0      0 192.168.0.104:8030      :::*                    LISTEN      3203/java           
tcp6       0      0 192.168.0.104:8031      :::*                    LISTEN      3203/java           
tcp6       0      0 192.168.0.104:8032      :::*                    LISTEN      3203/java           
tcp6       0      0 192.168.0.104:8033      :::*                    LISTEN      3203/java           
tcp6       0      0 :::8040                 :::*                    LISTEN      3367/java           
tcp6       0      0 :::8042                 :::*                    LISTEN      3367/java           
tcp6       0      0 :::22                   :::*                    LISTEN      914/sshd            
tcp6       0      0 192.168.0.104:8088      :::*                    LISTEN      3203/java           
tcp6       0      0 ::1:25                  :::*                    LISTEN      1164/master         
tcp6       0      0 :::13562                :::*                    LISTEN      3367/java           

50070端口，没有程序使用，怀疑是程序没有正常运行。

查看 hdfs-site.xml 文件，空的，没有配置。

添加配置：

<property>
        <name>dfs.namenode.http-addressname>
        <value>master:50070value>
property>

此时可以打开：

端口为 50070。可以看到此时有三个可用的 Datanode：