CentOS6.4下Hadoop1.1.2伪分布式环境搭建

 

使用VirtualBox搭建伪分布式环境，Linux为CentOS6.4，网络连接模式为Host-only

 

 物理环境虚拟机网卡地址设置为192.168.56.0/24网段

 设置CentOS的IP地址，必须和虚拟机网卡地址在同一网段，配置完CentOS的IP地址后重启一下网卡

[root@centos /]# service network restart
Shutting down loopback interface:                          [  OK  ]
Bringing up loopback interface:                            [  OK  ]
Bringing up interface Wired_connection_1:  Active connection state: activated
Active connection path: /org/freedesktop/NetworkManager/ActiveConnection/3
                                                           [  OK  ]
[root@centos /]# ifconfig
eth2      Link encap:Ethernet  HWaddr 08:00:27:B5:55:86
          inet addr:192.168.56.101  Bcast:192.168.56.255  Mask:255.255.255.0
          inet6 addr: fe80::a00:27ff:feb5:5586/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:115333 errors:0 dropped:0 overruns:0 frame:0
          TX packets:65446 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:153775846 (146.6 MiB)  TX bytes:5372883 (5.1 MiB)

 从物理机ping虚拟机CentOS地址

 关闭CentOS防火强

[root@centos /]# service iptables stop
iptables: Flushing firewall rules:                         [  OK  ]
iptables: Setting chains to policy ACCEPT: filter          [  OK  ]
iptables: Unloading modules:                               [  OK  ]
[root@centos /]# service iptables status
iptables: Firewall is not running.
[root@centos /]# chkconfig --list | grep iptables
iptables        0:off   1:off   2:on    3:on    4:on    5:on    6:off
[root@centos /]# chkconfig iptables off
[root@centos /]# chkconfig --list | grep iptables
iptables        0:off   1:off   2:off   3:off   4:off   5:off   6:off

设置SSH登录

ssh-keygen -t rsa//生成公钥/私钥
cp ~/.ssh/id_rsa.pub ~/.ssh/authorized_keys//拷贝文件
ssh centos//测试

  

 

 将jdk-6u24-linux-i586.bin、hadoop-1.1.2.tar.gz通过WinSCP上传到CentOS中，通过FTP这种方式传文件，我认为物理机和虚拟机传文件很方便，什么插件都不用装

给jdk-6u24-linux-i586.bin增加执行权限，就可以使用tab键补全

[root@centos local]# [root@centos local]# chmod u+x jdk-6u24-linux-i586.bin

CentOS自带一个OpenJDK

[root@centos local]# java -version
java version "1.7.0_09-icedtea"
OpenJDK Runtime Environment (rhel-2.3.4.1.el6_3-i386)
OpenJDK Client VM (build 23.2-b09, mixed mode)

解压HotSpot JDK

[root@centos local]# ./ jdk-6u24-linux-i586.bin
[root@centos local]# ls -l
drwxr-xr-x. 10 root root     4096 May 19 10:18 jdk1.6.0_24
-rwxr--r--.  1 root root 84927175 May  4 11:48 jdk-6u24-linux-i586.bin

 修改profile文件，增加JAVA_HOME和环境变量PTAH的配置

[root@centos local]# vim /etc/profile
export JAVA_HOME=/usr/local/jdk1.6.0_24
export PATH=.:$JAVA_HOME/bin:$PATH

 重新加载文件，验证OpenJDK是否切换为HotSpot

[root@centos local]# source /etc/profile
[root@centos local]# java -version
java version "1.6.0_24"
Java(TM) SE Runtime Environment (build 1.6.0_24-b07)
Java HotSpot(TM) Client VM (build 19.1-b02, mixed mode, sharing)

 解压hadoop-1.1.2.tar.gz

[root@centos local]# tar -xzvf hadoop-1.1.2.tar.gz

 修改profile文件增加HADOOP_HOME及环境变量

export JAVA_HOME=/usr/local/jdk1.6.0_24
export HADOOP_HOME=/usr/local/hadoop-1.1.2
export PATH=.:$HADOOP_HOME/bin:$JAVA_HOME/bin:$PATH

修改hadoop中conf目录下的4个配置文件

hadoop-env.sh

/usr/local/hadoop-1.1.2/conf/hadoop-env.sh

export JAVA_HOME=/usr/local/jdk1.6.0_24

core-site.xml，配置Hadoop Common Project相关的属性配置，Hadoop1.x框架基础晨星配置

/usr/local/hadoop-1.1.2/conf/core-site.xml

<configuration>
    <property>
        <!--指定NameNode主机名和端口号-->
        <name>fs.default.name</name>
        <value>hdfs://centos:9000</value>
    </property>
    <property>
        <!--指定Hadoop临时目录-->
        <name>hadoop.tmp.dir</name>
        <value>/usr/local/hadoop/tmp</value>
    </property>  
</configuration>

 hdfs-site.xml，配置HDFS相关属性

/usr/local/hadoop-1.1.2/conf/ hdfs-site.xml

<configuration>
    <property>
        <!--设置HDFS副本数-->
        <name>dfs.replication</name>
        <value>1</value>
    </property>
    <property>
        <!--是否进行权限检查-->
        <name>dfs.permissions</name>
        <value>false</value>
    </property>
</configuration>

mapred-site.xml，配置MapReduce相关属性

/usr/local/hadoop-1.1.2/conf/mapred-site.xml

<configuration>
    <property>
        <!--指定JobTracker主机与端口号-->
        <name>mapred.job.tracker</name>
        <value>centos:9001</value>
    </property>
</configuration>

 格式化namenode

[root@centos conf]# hadoop  namenode -format

 启动hadoop

[root@centos conf]# start-all.sh
Warning: $HADOOP_HOME is deprecated.
starting namenode, logging to /usr/local/hadoop-1.1.2/libexec/../logs/hadoop-root-namenode-centos.out
localhost: starting datanode, logging to /usr/local/hadoop-1.1.2/libexec/../logs/hadoop-root-datanode-centos.out
localhost: starting secondarynamenode, logging to /usr/local/hadoop-1.1.2/libexec/../logs/hadoop-root-secondarynamenode-centos.out
localhost: Exception in thread "main" java.net.UnknownHostException: unknown host: centos
localhost:      at org.apache.hadoop.ipc.Client$Connection.<init>(Client.java:233)
localhost:      at org.apache.hadoop.ipc.Client.getConnection(Client.java:1233)
localhost:      at org.apache.hadoop.ipc.Client.call(Client.java:1087)
localhost:      at org.apache.hadoop.ipc.RPC$Invoker.invoke(RPC.java:229)
localhost:      at $Proxy5.getProtocolVersion(Unknown Source)
localhost:      at org.apache.hadoop.ipc.RPC.getProxy(RPC.java:411)
localhost:      at org.apache.hadoop.ipc.RPC.getProxy(RPC.java:392)
localhost:      at org.apache.hadoop.ipc.RPC.getProxy(RPC.java:374)
localhost:      at org.apache.hadoop.ipc.RPC.getProxy(RPC.java:444)
starting jobtracker, logging to /usr/local/hadoop-1.1.2/libexec/../logs/hadoop-root-jobtracker-centos.out
localhost: starting tasktracker, logging to /usr/local/hadoop-1.1.2/libexec/../logs/hadoop-root-tasktracker-centos.out

 UnknownHostException的原因是mapred-site.xml、core-site.xml配置文件中主机名“centos”没能解析

1、配置主机名到192.168.56.101的映射

2、配置文件中用ip地址

启动hadoop，可以看到starting namenode、starting datanode、starting secondarynamenode、starting jobtracke、starting tasktracker启动，无异常

[root@centos conf]# start-all.sh
Warning: $HADOOP_HOME is deprecated.
starting namenode, logging to /usr/local/hadoop-1.1.2/libexec/../logs/hadoop-root-namenode-centos.out
localhost: starting datanode, logging to /usr/local/hadoop-1.1.2/libexec/../logs/hadoop-root-datanode-centos.out
localhost: starting secondarynamenode, logging to /usr/local/hadoop-1.1.2/libexec/../logs/hadoop-root-secondarynamenode-centos.out
starting jobtracker, logging to /usr/local/hadoop-1.1.2/libexec/../logs/hadoop-root-jobtracker-centos.out
localhost: starting tasktracker, logging to /usr/local/hadoop-1.1.2/libexec/../logs/hadoop-root-tasktracker-centos.out

 hadoop的每个节点都会以进程的方式启动，使用jps查看进程，如果看到

[root@centos conf]# jps
5791 NameNode
6123 JobTracker
6642 Jps
6040 SecondaryNameNode

 缺少DataNode，不管mapred-site.xml、core-site.xm两个配置文件中使用主机名还是ip地址，都要在

/etc/hosts

 中增加centos到192.168.51.101的地址映射，不然会缺少DataNode进程，修改hosts文件后重新启动hadoop

[root@centos /]# jps
9326 TaskTracker
9096 DataNode
9425 Jps
5791 NameNode
6123 JobTracker
6040 SecondaryNameNode

使用hadoop命令是出现了警告信息

Warning: $HADOOP_HOME is deprecated.

  原因是在hadoop-config.sh中出现了如下shell语句

if [ "$HADOOP_HOME_WARN_SUPPRESS" = "" ] && [ "$HADOOP_HOME" != "" ]; then
  echo "Warning: \$HADOOP_HOME is deprecated." 1>&2
  echo 1>&2

 只要【$HADOOP_HOME_WARN_SUPPRESS】不为空或者【$HADOOP_HOME】为空警告问题就解决了，在/etc/profile配置这两个变量

5个进程都启动了，验证一下，在浏览器输入两个地址

http://192.168.56.101:50070

http://192.168.56.101:50030看到如下信息

 

看到上面的信息就证明环境搭建成功

Yes！！！