【八】Hadoop分布式环境搭建

 概述：分布式核心思想是人多力量大，众人拾材火焰高；把众多计算机集中起来进行任务处理，其存储和运算能力就提高了，可以并行运算，但是众多PC维护管理也是一个问题，所谓众口难调，这就是鱼和熊掌不可兼得的道理，只能两害相侵，取其轻，来进行利益最大化处理。

本次实验使用三台虚拟机：master,node1,node2,其中master作为namenode，senondNameNode，以及JobTracker，另外两个几点作为dataNode和taskTracker，具体搭建过程如下：

1、配置host文件(或者使用DNS服务器)

      修改/etc/hosts文件

      IP地址 主机名

[root@bogon ~]# vi /etc/hosts

# Do not remove the following line, or various programs

# that require network functionality will fail.

127.0.0.1               localhost.localdomain localhost

::1             localhost6.localdomain6 localhost6

 

192.168.1.106  node1

192.168.1.107  master

192.168.1.110  node2

[root@bogon ~]# scp /etc/hosts  master:/etc/hosts

The authenticity of host 'master (192.168.1.107)' can't be established.

RSA key fingerprint is 42:d9:0b:a6:15:c2:23:c0:2d:d4:bd:88:4b:c5:dd:ff.

Are you sure you want to continue connecting (yes/no)? yes

Warning: Permanently added 'master,192.168.1.107' (RSA) to the list of known hosts.

hosts                                                                                                                                                        100%  252     0.3KB/s   00:00    

[root@bogon ~]# scp /etc/hosts  node2:/etc/hosts

2、建立hadoop运行账号

      配置运行hadoop的专用用户，当然使用超级用户root也不违法乱纪

3、配置ssh免密码接入

      每个节点都产生公钥和私钥，拷贝公钥到authorized_keys中

      公钥分发传递：然后把各个节点的公钥都拷贝到authorized_keys文件中

      生成秘钥到root目录 

ssh-keygen -t rsa

公钥文件放入authorized_keys

cd .ssh/

cp id_rsa.pub authorized_keys

4、安装JDK

[root@bogon bin]# vi ~/.bash_profile 

JAVA_HOME=/usr/java/jdk1.7.0_67

PATH=$PATH:$HOME/bin:$JAVA_HOME/bin

export PATH  JAVA_HOME

 验证：

 [root@bogon bin]# ssh node1

Last login: Tue Dec  8 11:22:14 2015 from 192.168.1.103

[root@node1 ~]# source .bash_profile 

[root@node1 ~]# echo $JAVA_HOME

/usr/java/jdk1.7.0_67

[root@node1 ~]# jps

 

==========================================================

5、下载并且解压hadoop安装包

1)解压，配置hadoop环境变量bin

HADOOP_HOME

PATH: HADOOP_HOME/bin
 

6、配置 文件 修改

【hadoop-env.sh】

JAVA_HOME

【core-site.xml】

<configuration>

<property>

        <name>fs.default.name</name>

        <value>hdfs://master:9000</value>

</property>

<property>

        <name>hadoop.tmp.dir</name>

        <value>/opt/hadoop_data</value>

</property>

</configuration>

 

【hdfs-site.xml】

<configuration>

<property>

        <name>dfs.replication</name>

        <value>2</value>

</property>

<property>

        <name>dfs.permissions</name>

        <value>flase</value>

</property>

</configuration>

 

【mapred-site.xml】

<?xml version="1.0"?>

<?xml-stylesheet type="text/xsl" href="configuration.xsl"?>

<configuration>

<property>

        <name>mapred.job.tracker</name>

        <value>http://master:9001</value>

</property>

</configuration>

 

7、配置master和slaves文件

masters配置主节点

slaves配置从节点

[root@node2 conf]# cat masters 

master

[root@node2 conf]# cat slaves 

node1

node2

 

8、向各个节点复制hadoop

[root@master ~]# scp .bash_profile  node1:~/

[root@master ~]# scp .bash_profile  node2:~/

 

[root@node2 opt]#scp -r hadoop node1:/opt

[root@node2 opt]#scp -r hadoop master:/opt

==========================================================

 

9、格式化namenode

仅仅格式化master节点   

hadoop namenode -format

 

[root@master ~]# hadoop namenode -format

Warning: $HADOOP_HOME is deprecated.

15/12/08 12:41:19 INFO namenode.NameNode: STARTUP_MSG: 

/************************************************************

STARTUP_MSG: Starting NameNode

STARTUP_MSG:   host = master/192.168.1.107

STARTUP_MSG:   args = [-format]

STARTUP_MSG:   version = 1.1.2

STARTUP_MSG:   build = https://svn.apache.org/repos/asf/hadoop/common/branches/branch-1.1 -r 1440782; compiled by 'hortonfo' on Thu Jan 31 02:03:24 UTC 2013

************************************************************/

15/12/08 12:41:25 INFO util.GSet: VM type       = 64-bit

15/12/08 12:41:25 INFO util.GSet: 2% max memory = 19.33375 MB

15/12/08 12:41:25 INFO util.GSet: capacity      = 2^21 = 2097152 entries

15/12/08 12:41:25 INFO util.GSet: recommended=2097152, actual=2097152

15/12/08 12:41:29 INFO namenode.FSNamesystem: fsOwner=root

15/12/08 12:41:29 INFO namenode.FSNamesystem: supergroup=supergroup

15/12/08 12:41:29 INFO namenode.FSNamesystem: isPermissionEnabled=true

15/12/08 12:41:29 INFO namenode.FSNamesystem: dfs.block.invalidate.limit=100

15/12/08 12:41:29 INFO namenode.FSNamesystem: isAccessTokenEnabled=false accessKeyUpdateInterval=0 min(s), accessTokenLifetime=0 min(s)

15/12/08 12:41:29 INFO namenode.NameNode: Caching file names occuring more than 10 times 

15/12/08 12:41:33 INFO common.Storage: Image file of size 110 saved in 0 seconds.

15/12/08 12:41:33 INFO namenode.FSEditLog: closing edit log: position=4, editlog=/opt/hadoop_data/dfs/name/current/edits

15/12/08 12:41:33 INFO namenode.FSEditLog: close success: truncate to 4, editlog=/opt/hadoop_data/dfs/name/current/edits

15/12/08 12:41:34 INFO common.Storage: Storage directory /opt/hadoop_data/dfs/name has been successfully formatted.

15/12/08 12:41:34 INFO namenode.NameNode: SHUTDOWN_MSG: 

/************************************************************

SHUTDOWN_MSG: Shutting down NameNode at master/192.168.1.107

************************************************************/

 

10、启动hadoop

在master节点进行启动，master是火车头，统领武林

start-all.sh

[root@master ~]# start-all.sh

Warning: $HADOOP_HOME is deprecated.

starting namenode, logging to /opt/hadoop/libexec/../logs/hadoop-root-namenode-master.out

node2: starting datanode, logging to /opt/hadoop/libexec/../logs/hadoop-root-datanode-node2.out

node1: starting datanode, logging to /opt/hadoop/libexec/../logs/hadoop-root-datanode-node1.out

The authenticity of host 'master (192.168.1.107)' can't be established.

RSA key fingerprint is 42:d9:0b:a6:15:c2:23:c0:2d:d4:bd:88:4b:c5:dd:ff.

Are you sure you want to continue connecting (yes/no)? yes

master: Warning: Permanently added 'master,192.168.1.107' (RSA) to the list of known hosts.

master: starting secondarynamenode, logging to /opt/hadoop/libexec/../logs/hadoop-root-secondarynamenode-master.out

starting jobtracker, logging to /opt/hadoop/libexec/../logs/hadoop-root-jobtracker-master.out

node2: starting tasktracker, logging to /opt/hadoop/libexec/../logs/hadoop-root-tasktracker-node2.out

node1: starting tasktracker, logging to /opt/hadoop/libexec/../logs/hadoop-root-tasktracker-node1.out

 

11、验证进程

  使用jps验证各个后台进程是否启动成功

[root@master ~]# jps

3614 NameNode

3763 SecondaryNameNode

3916 Jps

3837 JobTracker

 

[root@node1 ~]# jps

3513 Jps

[root@node1 ~]# jps

3626 TaskTracker

3555 DataNode

3667 Jps

 

[root@node2 ~]# jps

3573 DataNode

3627 TaskTracker

3698 Jps

[root@node2 ~]# 

 

[root@master bin]# hadoop dfsadmin -report

Warning: $HADOOP_HOME is deprecated.

Configured Capacity: 36889264128 (34.36 GB)

Present Capacity: 28400594944 (26.45 GB)

DFS Remaining: 28400537600 (26.45 GB)

DFS Used: 57344 (56 KB)

DFS Used%: 0%

Under replicated blocks: 0

Blocks with corrupt replicas: 0

Missing blocks: 0

-------------------------------------------------

Datanodes available: 2 (2 total, 0 dead)

Name: 192.168.1.106:50010

Decommission Status : Normal

Configured Capacity: 18444632064 (17.18 GB)

DFS Used: 28672 (28 KB)

Non DFS Used: 4213334016 (3.92 GB)

DFS Remaining: 14231269376(13.25 GB)

DFS Used%: 0%

DFS Remaining%: 77.16%

Last contact: Tue Dec 08 12:58:40 PST 2015

 

Name: 192.168.1.110:50010

Decommission Status : Normal

Configured Capacity: 18444632064 (17.18 GB)

DFS Used: 28672 (28 KB)

Non DFS Used: 4275335168 (3.98 GB)

DFS Remaining: 14169268224(13.2 GB)

DFS Used%: 0%

DFS Remaining%: 76.82%

Last contact: Tue Dec 08 12:58:39 PST 2015

 

启动停止

[root@master bin]# stop-all.sh

Warning: $HADOOP_HOME is deprecated.

no jobtracker to stop

node1: no tasktracker to stop

node2: no tasktracker to stop

stopping namenode

node2: stopping datanode

node1: stopping datanode

master: stopping secondarynamenode