hadoop的单机版测试和集群节点的搭建

Hadoop技术原理：

Hdfs主要模块：NameNode、DataNode
Yarn主要模块：ResourceManager、NodeManager
HDFS主要模块及运行原理：

1）NameNode：

功能：是整个文件系统的管理节点。维护整个文件系统的文件目录树，文件/目录的元数据和
每个文件对应的数据块列表。接收用户的请求。
2）DataNode：

功能：是HA（高可用性）的一个解决方案，是备用镜像，但不支持热备

一、hadoop单机版测试

1.创建用户并安装

[root@server1 ~]# ls
anaconda-ks.cfg  hadoop-3.0.3.tar.gz  jdk-8u181-linux-x64.tar.gz
[root@server1 ~]# useradd -u 1000 hadoop
[root@server1 ~]# passwd hadoop
Changing password for user hadoop.
New password:
BAD PASSWORD: The password is shorter than 8 characters
Retype new password:
passwd: all authentication tokens updated successfully.
[root@server1 ~]# mv hadoop-3.0.3.tar.gz jdk-8u181-linux-x64.tar.gz /home/hadoop/
[root@server1 ~]# su - hadoop
[hadoop@server1 ~]$ ls
hadoop-3.0.3.tar.gz  jdk-8u181-linux-x64.tar.gz
[hadoop@server1 ~]$ tar zxf jdk-8u181-linux-x64.tar.gz
[hadoop@server1 ~]$ ls
hadoop-3.0.3.tar.gz  jdk1.8.0_181  jdk-8u181-linux-x64.tar.gz
[hadoop@server1 ~]$ ln -s jdk1.8.0_181/ java
[hadoop@server1 ~]$ tar zxf hadoop-3.0.3.tar.gz
[hadoop@server1 ~]$ ls
hadoop-3.0.3         java          jdk-8u181-linux-x64.tar.gz
hadoop-3.0.3.tar.gz  jdk1.8.0_181
[hadoop@server1 ~]$ ln -s hadoop-3.0.3 hadoop
[hadoop@server1 ~]$ ls
hadoop        hadoop-3.0.3.tar.gz  jdk1.8.0_181
hadoop-3.0.3  java                 jdk-8u181-linux-x64.tar.gz

2、配置环境变量

[hadoop@server1 hadoop]$ cd /home/hadoop/hadoop/etc/hadoop/
[hadoop@server1 hadoop]$ pwd
/home/hadoop/hadoop/etc/hadoop
[hadoop@server1 hadoop]$ vim hadoop-env.sh

[hadoop@server1 hadoop]$ cd
[hadoop@server1 ~]$ vim .bash_profile

3、测试

[hadoop@server1 ~]$ source .bash_profile
[hadoop@server1 ~]$ jps
942 Jps
[hadoop@server1 ~]$ cd /home/hadoop/hadoop
[hadoop@server1 hadoop]$ pwd
/home/hadoop/hadoop
[hadoop@server1 hadoop]$ mkdir input
[hadoop@server1 hadoop]$ cp etc/hadoop/*.xml input/
[hadoop@server1 hadoop]$ bin/hadoop jar share/hadoop/mapreduce/hadoop-mapreduce-examples-3.0.3.jar grep input output 'dfs[a-z.]+'
[hadoop@server1 hadoop]$ cd output/
[hadoop@server1 output]$ ls
part-r-00000  _SUCCESS
[hadoop@server1 output]$ cat *
1   dfsadmin

二、伪分布式
1.编辑文件

[hadoop@server1 output]$ cd /home/hadoop/hadoop/etc/hadoop/
[hadoop@server1 hadoop]$ pwd
/home/hadoop/hadoop/etc/hadoop
[hadoop@server1 hadoop]$ vim core-site.xml

[hadoop@server1 hadoop]$ vim hdfs-site.xml

2.生成密钥做免密连接

[hadoop@server1 sbin]$ ssh-keygen
Generating public/private rsa key pair.
Enter file in which to save the key (/home/hadoop/.ssh/id_rsa):
Enter passphrase (empty for no passphrase):
Enter same passphrase again:
Your identification has been saved in /home/hadoop/.ssh/id_rsa.
Your public key has been saved in /home/hadoop/.ssh/id_rsa.pub.
The key fingerprint is:
8e:f1:1d:4e:29:e2:56:eb:42:4f:79:f2:f3:89:42:69 hadoop@server1
The key's randomart image is:
+--[ RSA 2048]----+
|                 |
|                 |
|                 |
|           .     |
|      o So+      |
|     ..BE*..     |
|     .+=++o      |
|     ...o o. .   |
|       ....oo    |
+-----------------+
[hadoop@server1 sbin]$ ssh-copy-id localhost
/bin/ssh-copy-id: INFO: attempting to log in with the new key(s), to filter out any that are already installed
/bin/ssh-copy-id: INFO: 1 key(s) remain to be installed -- if you are prompted now it is to install the new keys
hadoop@localhost's password: Number of key(s) added: 1Now try logging into the machine, with:   "ssh 'localhost'"
and check to make sure that only the key(s) you wanted were added.

3.格式化并开启服务

[hadoop@server1 hadoop]$ bin/hdfs namenode -format
[hadoop@server1 hadoop]$ pwd
/home/hadoop/hadoop
[hadoop@server1 sbin]$ ./start-dfs.sh
Starting namenodes on [localhost]
Starting datanodes
Starting secondary namenodes [server1]
[hadoop@server1 sbin]$ jps
11060 NameNode
11159 DataNode
11341 SecondaryNameNode
11485 Jps

4.浏览器查看

http://172.25.11.1:9870

5.测试，创建目录，并上传

[hadoop@server1 hadoop]$ bin/hdfs dfs -mkdir -p /user/hadoop
[hadoop@server1 hadoop]$ bin/hdfs dfs -ls
[hadoop@server1 hadoop]$ bin/hdfs dfs -put input
[hadoop@server1 hadoop]$ bin/hdfs dfs -ls
Found 1 items
drwxr-xr-x   - hadoop supergroup          0 2019-05-19 01:47 input

6. 删除input和output文件，重新执行命令

[hadoop@server1 hadoop]$ rm -fr input/ output/
[hadoop@server1 hadoop]$ bin/hadoop jar share/hadoop/mapreduce/hadoop-mapreduce-examples-3.0.3.jar grep input output 'dfs[a-z.]+'
[hadoop@server1 hadoop]$ ls
bin  etc  include  lib  libexec  LICENSE.txt  logs  NOTICE.txt  README.txt  sbin  share

此时input和output不会出现在当前目录下，而是上传到了分布式文件系统中，网页上可以看到

[hadoop@server1 hadoop]$ bin/hdfs dfs -cat output/*
1   dfsadmin
[hadoop@server1 hadoop]$ bin/hdfs dfs -get output  ##从分布式系统中get下来output目录
[hadoop@server1 hadoop]$ cd output/
[hadoop@server1 output]$ ls
part-r-00000  _SUCCESS

三、分布式
1.先停掉服务，清除原来的数据

[hadoop@server1 hadoop]$ sbin/stop-dfs.sh
Stopping namenodes on [localhost]
Stopping datanodes
Stopping secondary namenodes [server1]
[hadoop@server1 hadoop]$ cd /tmp/
[hadoop@server1 tmp]$ ls
hadoop  hadoop-hadoop  hsperfdata_hadoop
[hadoop@server1 tmp]$ rm -fr *

2.新开两个虚拟机，当做节点
创建用户

[root@server2 ~]# useradd -u 1000 hadoop
[root@server3 ~]# useradd -u 1000 hadoop

安装nfs-utils

[root@server1 ~]# yum install -y nfs-utils
[root@server2 ~]# yum install -y nfs-utils
[root@server3 ~]# yum install -y nfs-utils[root@server1 ~]# systemctl start rpcbind
[root@server2 ~]# systemctl start rpcbind
[root@server3 ~]# systemctl start rpcbind

3.server1开启服务，配置

[root@server1 ~]# systemctl start nfs-server
[root@server1 ~]# vim /etc/exports
/home/hadoop   *(rw,anonuid=1000,anongid=1000)[root@server1 ~]# exportfs -rv
exporting *:/home/hadoop
[root@server1 ~]# showmount -e
Export list for server1:
/home/hadoop *

4.server2,3挂载

[root@server2 ~]# vim /etc/hosts
[root@server2 ~]# mount 172.25.11.1:/home/hadoop /home/hadoop
[root@server2 ~]# df
Filesystem               1K-blocks    Used Available Use% Mounted on
/dev/sda3                 18351104 1092520  17258584   6% /
devtmpfs                    498480       0    498480   0% /dev
tmpfs                       508264       0    508264   0% /dev/shm
tmpfs                       508264    6736    501528   2% /run
tmpfs                       508264       0    508264   0% /sys/fs/cgroup
/dev/sda1                   508580  110596    397984  22% /boot
tmpfs                       101656       0    101656   0% /run/user/0
172.25.11.1:/home/hadoop  18351104 2790656  15560448  16% /home/hadoop[root@server3 ~]# mount 172.25.11.1:/home/hadoop /home/hadoop
[root@server3 ~]# df
Filesystem               1K-blocks    Used Available Use% Mounted on
/dev/sda3                 18351104 1092468  17258636   6% /
devtmpfs                    498480       0    498480   0% /dev
tmpfs                       508264       0    508264   0% /dev/shm
tmpfs                       508264    6736    501528   2% /run
tmpfs                       508264       0    508264   0% /sys/fs/cgroup
/dev/sda1                   508580  110596    397984  22% /boot
tmpfs                       101656       0    101656   0% /run/user/0
172.25.11.1:/home/hadoop  18351104 2790656  15560448  16% /home/hadoop

此时使用hadoop用户时可以直接从server1登陆到server2和server3的

5.重新编辑文件

[root@server1 hadoop]# pwd
/home/hadoop/hadoop/etc/hadoop
[root@server1 hadoop]# vim core-site.xml<configuration><property><name>fs.defaultFS</name><value>hdfs://172.25.11.1:9000</value></property>
</configuration>[root@server1 hadoop]# vim hdfs-site.xml<configuration><property><name>dfs.replication</name><value>2</value> ##改为两个节点</property>
</configuration>[root@server1 hadoop]# vim workers
[root@server1 hadoop]# cat workers
172.25.11.2
172.25.11.3

在一个地方编辑，其他节点都有了

[hadoop@server2 hadoop]$ cat workers
172.25.11.2
172.25.11.3[root@server3 ~]# cat /home/hadoop/hadoop/etc/hadoop/workers
172.25.11.2
172.25.11.3

6.格式化，并启动服务

[hadoop@server1 hadoop]$ pwd
/home/hadoop/hadoop
[hadoop@server1 hadoop]$ bin/hdfs namenode -format
[hadoop@server1 hadoop]$ sbin/start-dfs.sh
Starting namenodes on [server1]
Starting datanodes
172.25.11.2: Warning: Permanently added '172.25.11.2' (ECDSA) to the list of known hosts.
172.25.11.3: Warning: Permanently added '172.25.11.3' (ECDSA) to the list of known hosts.
Starting secondary namenodes [server1]
[hadoop@server1 hadoop]$ sbin/start-dfs.sh
Starting namenodes on [server1]
Starting datanodes
Starting secondary namenodes [server1]
[hadoop@server1 hadoop]$ vim /etc/hosts
[hadoop@server1 hadoop]$ vim /etc/hosts
[hadoop@server1 hadoop]$ jps
14000 SecondaryNameNode ##生成SecondaryNameNode
13814 NameNode
14153 Jps

从节点可以看到datanode信息

[hadoop@server2 ~]$ jps
10336 Jps
10273 DataNode
[hadoop@server3 ~]$ jps
1141 DataNode
1230 Jps

7.测试

[hadoop@server1 hadoop]$ bin/hdfs dfs -mkdir -p /user/hadoop
[hadoop@server1 hadoop]$ bin/hdfs dfs -mkdir input
[hadoop@server1 hadoop]$ bin/hdfs dfs -put etc/hadoop/*.xml input
[hadoop@server1 hadoop]$ bin/hadoop jar share/hadoop/mapreduce/hadoop-mapreduce-examples-3.0.3.jar grep input output 'dfs[a-z.]+'

8.网页上查看，有两个节点，且数据已经上传

9.server4模拟客户端

[root@server4 ~]# useradd -u  1000 hadoop
[root@server4 ~]# vim /etc/hosts
[root@server4 ~]# yum  install -y  nfs-utils[root@server4 ~]# systemctl start rpcbind
[root@server4 ~]# mount 172.25.11.1:/home/hadoop /home/hadoop
[root@server4 ~]# su - hadoop
[hadoop@server4 ~]$ cd /home/hadoop/hadoop/etc/hadoop/
[hadoop@server4 hadoop]$ vim workers
[hadoop@server4 hadoop]$ cat workers
172.25.11.2
172.25.11.3
172.25.11.4
[hadoop@server4 hadoop]$ sbin/hadoop-daemon.sh start
[hadoop@server4 hadoop]$ jps
2609 Jps
2594 DataNode

浏览器查看，节点添加成功

[hadoop@server4 hadoop]$ dd if=/dev/zero of=bigfile bs=1M count=500
500+0 records in
500+0 records out
524288000 bytes (524 MB) copied, 25.8653 s, 20.3 MB/s
[hadoop@server4 hadoop]$ bin/hdfs dfs -put bigfile

显示bigfile已经上传成功