1.1.1 环境准备
本次由一台centos虚拟服务器搭建hadoop平台，机器信息如表１所示：
表１ 主机环境准备
|
名称 |
信息 |
|
IP |
10.1.1.20 |
|
hostname |
Master.hadoop |
为方便使用，现给出主机环境方面需要修改的地方：
● IP地址修改
IP地址位于/etc/sysconfig/network-scripts/目录中，通过vi编辑ifcfg-eth0文件修改成如下所示结构即可：
|
[root@master network-scripts]# cd /etc/sysconfig/network-scripts/ [root@master network-scripts]# cat ifcfg-eth0 DEVICE="eth0" ONBOOT=yes TYPE=Ethernet BOOTPROTO=none IPADDR=10.1.1.20 PREFIX=24 GATEWAY=10.1.1.1 DEFROUTE=yes HWADDR=00:30:16:AF:00:D1 |
● hostname修改
Hostname修改位于/etc/sysconfig/network文件中，其修改后的结果如下所示：
|
[root@master network-scripts]# cat /etc/sysconfig/network NETWORKING=yes HOSTNAME=master.hadoop |
● DNS修改
DNS位于/etc/hosts文件中，修改的结果如下所示：
|
[root@master network-scripts]# cat /etc/hosts 10.1.1.20 master.hadoop master 127.0.0.1 localhost.localdomain localhost |
● 环境测试
通过ping测试master.hadoop是否畅通：
|
[root@master network-scripts]# ping master.hadoop PING master.hadoop (10.1.1.20) 56(84) bytes of data. 64 bytes from master.hadoop (10.1.1.20): icmp_seq=1 ttl=64 time=0.040 ms 64 bytes from master.hadoop (10.1.1.20): icmp_seq=2 ttl=64 time=0.016 ms --- master.hadoop ping statistics --- 2 packets transmitted, 2 received, 0% packet loss, time 1467ms rtt min/avg/max/mdev = 0.016/0.028/0.040/0.012 ms |
1.1.2Java安装与部署
Hadoop需要java环境支持，通常需要java 1.6版本以上，因此可以通过去java官方网站下载JDK环境，下载地址为：
http://www.oracle.com/technetwork/java/javase/downloads/jdk-6u25-download-346242.html
从本链接中选择jdk-6u25-linux-x64-rpm.bin，在接受协议后方可下载到本地；
● Java安装
将下载到后java文件传至master.hadoop主机/home目录中，下面可以进行对其进行安装：
|
[root@master home]# chmod u+x jdk-6u25-linux-x64-rpm.bin [root@master home]# ./jdk-6u25-linux-x64-rpm.bin |
● Java配置
Java安装完毕后，可以对java目录信息进行环境变量配置，配置信息需增加至文件/etc/profile之中，具体如下所示：
|
[root@master home]#vi /etc/profile JAVA_HOME=/usr/java/jdk1.6.0_25 CLASSPATH=.:$JAVA_HOME/lib PATH=$PATH:$JAVA_HOME/bin:$JAVA_HOME/jre/bin |
环境变量配置完毕后，通过命令进行检验并生效：
|
[root@master jdk1.6.0_25]# source /etc/profile |
1.1.3 SSH配置
通过配置SSH实现基于公钥方式无密码登录，具体操作步骤为：创建一个新的hadoop帐户、生成这个帐户的SSH公钥、配置公钥授权文件、设置SSH服务登录方式等，下面给出具体方式：
● 创建hadoop帐户
|
[root@master jdk1.6.0_25]# useradd hadoop #创建帐号 [root@master jdk1.6.0_25]# passwd hadoop #配置密码 |
● 生成公钥
|
[hadoop@master ~]$ ssh-keygen #生成SSH认证公钥，连续回车即可 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: 86:b5:d9:6a:ea:03:4e:5a:97:e5:24:5b:1f:65:41:89 [email protected] The key's randomart image is: +--[ RSA 2048]----+ | ooo | | E + | | . o | | .o++. | | .OS... | | + +.... | | = o o | | . . .o | | .o. | +-----------------+ [hadoop@master ~]$ cd .ssh/ [hadoop@master .ssh]$ ls id_rsa id_rsa.pub |
● 配置授权
|
[hadoop@master ~]$ cat ~/.ssh/id_rsa.pub >> ~/.ssh/authorized_keys [hadoop@master ~]$ chmod 700 ~/.ssh [hadoop@master ~]$ chmod 600 ~/.ssh/authorized_keys
|
● 测试
|
[hadoop@master jdk1.6.0_25]$ ssh master.hadoop Last login: Wed Jun 13 18:29:29 2012 from master.hadoop
|
1.1.4 Hadoop安装与配置
使用的Hadoop版本是hadoop-0.20.2.tar.gz，下载地址为：
http://mirror.bit.edu.cn/apache/hadoop/common/hadoop-0.20.2/hadoop-0.20.2.tar.gz
● Hadoop安装
|
[root@master home]# tar xzvf hadoop-0.20.2.tar.gz [root@master home]# mv hadoop-0.20.2 /usr/local [root@master home]# cd /usr/local [root@master local]# ls bin etc games hadoop-0.20.2 include lib lib64 libexec sbin share src [root@master local]# mv hadoop-0.20.2/ hadoop [root@master local]# ls bin etc games hadoop include lib lib64 libexec sbin share src [root@master local]# chown -R hadoop:hadoop /usr/local/hadoop/ #修改权限 |
● 环境变量配置
跟配置JAVA一样配置hadoop环境变量，编辑文件/etc/profile，同时也要修改hadoop内部环境变量/hadoop/conf/hadoop_env.sh，具体细节如下所示：
|
[root@master local]# vi /etc/profile HADOOP_HOME=/usr/local/hadoop HADOOP_CONF_DIR=$HADOOP_HOME/conf CLASSPAH=.:$JAVA_HOME/lib:$HADOOP_HOME/lib PATH=$PATH:$JAVA_HOME/bin:$JAVA_HOME/jre/bin:$HADOOP_HOME/bin "/etc/profile" 73L, 1660C written [root@master local]# source /etc/profile [root@master conf]# vi hadoop-env.sh export JAVA_HOME=$JAVA_HOME [root@master bin]# export JAVA_HOME [root@master bin]# export HADOOP_HOME [root@master bin]# export HADOOP_CONF_DIR |
● hadoop文件配置
配置三个xml文件，分别为：core-site.xml、hdfs-site.xml、mapred-site.xml，配置效果如下所示：
文件：core-site.xml
|
[root@master conf]# vi core-site.xml <?xml version="1.0"?> <?xml-stylesheet type="text/xsl" href="configuration.xsl"?>
<!-- Put site-specific property overrides in this file. -->
<configuration> <property> <name>fs.default.name</name> <value>hdfs://localhost:9000</value> </property> </configuration>
|
文件：hdfs-site.xml
|
[root@master conf]# vi hdfs-site.xml <?xml version="1.0"?> <?xml-stylesheet type="text/xsl" href="configuration.xsl"?>
<!-- Put site-specific property overrides in this file. -->
<configuration> <property> <name>dfs.replication</name> <value>1</value> </property>
</configuration> |
文件：mapred-site.xml
|
[root@master conf]# vi mapred-site.xml <?xml version="1.0"?> <?xml-stylesheet type="text/xsl" href="configuration.xsl"?>
<!-- Put site-specific property overrides in this file. -->
<configuration> <property> <name>mapred.job.tracker</name> <value>localhost:9001</value> </property>
</configuration> |
● hadoop格式化文件系统
切换到bin目录，找到可执行文件hadoop，执行文件系统格式化操作：
|
[root@master bin]# hadoop namenode -format |
● 启动hadoop
|
[root@master bin]# ./start-all.sh starting namenode, logging to /var/local/logs/hadoop-root-namenode-master.hadoop.out localhost: starting datanode, logging to /var/local/logs/hadoop-root-datanode-master.hadoop.out localhost: starting secondarynamenode, logging to /var/local/logs/hadoop-root-secondarynamenode-master.hadoop.out starting jobtracker, logging to /var/local/logs/hadoop-root-jobtracker-master.hadoop.out localhost: starting tasktracker, logging to /var/local/logs/hadoop-root-tasktracker-master.hadoop.out |
1.1.5 Hadoop测试
|
[root@master hadoop]# jps 2459 JobTracker 2284 DataNode 2204 NameNode 2860 Jps 2382 SecondaryNameNode 2575 TaskTracker |
