基于Hadoop1.2.1完全分布式集群的部署

一、准备工作

同一个局域网中的三台Linux虚拟机，发行版本均使用64位CentOS6.3,主机是 Windows 10 64位操作系统；通过 vmware workstation 实现三台虚机，这样就形成了一个以物理机为DNS服务器的局域网，物理机和3台虚机都有一个局域网IP，从而实现相互之间的通信。

Hadoop是一个用java语言编程的开源软件，所以需要安装JDK，小编采用的JDK的版本是最新的jdk1.8；此外，Hadoop集群部分功能是用perl语言实现的，因此，还需安装perl环境；集群之间的通讯是通过SSH实现的，这就不需要小编介绍啦！你懂的......

安装Linux后一定要确讣iptables,selinux等防火墙戒访问控制机制已经关闭，否则实
验很可能受影响.

本次试验搭建的环境为：

namenode : 192.168.115.130 matser

datanode1：192.168.115.131 slave

datanode2：192.168.115.132 slave

二、配置hosts

在所有节点上（namenode、datanode1、datanode2）的终端上通过 vi /etc/hosts上添加如下代码：

192.168.115.130 namenode
192.168.115.131 datanode1
192.168.115.132 datanode2

查看能否ping通，若出现下图，标识配置hosts成功：

三、JDK的安装

终端使用wget下载 jdk-8u111-linux-x64.tar.gz

wge http://download.oracle.com/otn-pub/java/jdk/8u111-b14/jdk-8u111-linux-x64.tar.gz[/code] 
解压 tar -xzvf  jdk-8u111-linux-x64.tar.gz

[root@namenode tpf]# tar -xzvf  jdk-8u111-linux-x64.tar.gz


配置环境变量 vi /etc/profile ，在文件的结尾处添加如下代码，保存退出。

#JAVA
JAVA_HOME=/usr/local/jdk1.8.0_111
PATH=$JAVA_HOME/bin:$JAVA_HOME/jre/bin:$PATH
CLASSPATH=.:$JAVA_HOME/lib/dt.jar:$JAVA_HOME/lib/tools.jar
export JAVA_HOME PATH CLASSPATH


执行source /etc/profile，使修改的文件生效。

查看文件是否生效 echo $PATH

[root@namenode Desktop]# echo $PATH
/usr/local/jdk1.8.0_111/bin:/usr/local/jdk1.8.0_111/jre/bin:/usr/local/bin:/usr/bin:/bin:/usr/local/sbin:/usr/sbin:/sbin:/home/tpf/bin


依次输入如下三个命令，出现下图情况，表示JDK安装成功；

[root@namenode Desktop]# java -version
java version "1.8.0_111"
Java(TM) SE Runtime Environment (build 1.8.0_111-b14)
Java HotSpot(TM) 64-Bit Server VM (build 25.111-b14, mixed mode)


常规来说，如果出现上图，JDK的安装可能是成功的，但要想确保安装准确无误，需要进一步验证（见下图）：

[root@namenode Desktop]# java
Usage: java [-options] class [args...]
(to execute a class)
or  java [-options] -jar jarfile [args...]
(to execute a jar file)
where options include:
-d32	  use a 32-bit data model if available
-d64	  use a 64-bit data model if available
-server	  to select the "server" VM
The default VM is server.

-cp <class search path of directories and zip/jar files>
-classpath <class search path of directories and zip/jar files>
A : separated list of directories, JAR archives,
and ZIP archives to search for class files.
-D<name>=<value>
set a system property
-verbose:[class|gc|jni]

[root@namenode Desktop]# javac
Usage: javac <options> <source files>
where possible options include:
-g                         Generate all debugging info
-g:none                    Generate no debugging info
-g:{lines,vars,source}     Generate only some debugging info
-nowarn                    Generate no warnings
-verbose                   Output messages about what the compiler is doing
-deprecation               Output source locations where deprecated APIs are used
-classpath <path>          Specify where to find user class files and annotation processors
-cp <path>                 Specify where to find user class files and annotation processors
-sourcepath <path>         Specify where to find input source files
-bootclasspath <path>      Override location of bootstrap class files
-extdirs <dirs>            Override location of installed extensions
-endorseddirs <dirs>       Override location of endorsed standards path
-proc:{none,only}          Control whether annotation processing and/or compilation is done.
-processor <class1>[,<class2>,<class3>...] Names of the annotation processors to r

如果出现上述图形的情况，小编恭喜你JDK安装成功啦！

四、SSH互信
在虚机192.168.115.130/namenode节点上root权限下运行命令 ssh-keygen -t rsa

[root@namenode tpf]# ssh-keygen -t rsa
Generating public/private rsa key pair.
Enter file in which to save the key (/root/.ssh/id_rsa):
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:
2d:ed:ec:31:00:eb:18:23:59:83:8b:1f:df:ee:73:9b root@namenode
The key's randomart image is:
+--[ RSA 2048]----+
|                 |
|   .             |
|  . o .          |
| . + . o o       |
|. = o . S o      |
| . + *   =       |
|  . o o   =      |
|     .. .o o     |
|     .ooE..      |
+-----------------+


查看密钥

[root@namenode tpf]# cd /root/
[root@namenode ~]# ls
anaconda-ks.cfg  Desktop  Documents  Downloads  install.log  install.log.syslog  Music  Pictures  Public  Templates  Videos
[root@namenode ~]# ls -a
.                .bash_history  .bashrc  .dbus      Downloads  .gconfd  .gnupg           .gvfs          install.log.syslog  .nautilus          Public         .recently-used.xbel  .tcshrc    .xauthCtsxNO
..               .bash_logout   .config  Desktop    .esd_auth  .gnome2  .gstreamer-0.10  .ICEauthority  .local              .oracle_jre_usage  .pulse         .spice-vdagent       Templates
anaconda-ks.cfg  .bash_profile  .cshrc   Documents  .gconf     .gnote   .gtk-bookmarks   install.log    Music               Pictures           .pulse-cookie  .ssh                 Videos
[root@namenode ~]# cd .ssh/
[root@namenode .ssh]# ls
id_rsa  id_rsa.pub  known_hosts


查看文件的属性，确保下图所示的文件属性

[root@namenode .ssh]# ls -l
total 12
-rw-------. 1 root root 1675 Nov 25 23:03 id_rsa
-rw-r--r--. 1 root root  395 Nov 25 23:03 id_rsa.pub
-rw-r--r--. 1 root root 2392 Nov 25 11:10 known_hosts


转到虚机192.168.115.131 slave/datanode1节点上以root权限重复上述步骤生成密钥

[root@datanode2 ~]# cd /home/datanode2/
[root@datanode2 datanode2]# pwd
/home/datanode2
[root@datanode2 datanode2]# ssh-keygen -t rsa
Generating public/private rsa key pair.
Enter file in which to save the key (/root/.ssh/id_rsa):
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:
a9:da:e2:80:3a:d0:a9:1b:65:c0:c7:e6:10:61:a7:65 root@datanode2
The key's randomart image is:
+--[ RSA 2048]----+
| +.E             |
|o B              |
|.+ +             |
| .=      .       |
| .oo    S        |
|.+o    .         |
|+..   .          |
|+. ..o           |
|oo .o..          |
+-----------------+
[root@datanode2 datanode2]# cd /root/
[root@datanode2 ~]# ls
anaconda-ks.cfg  install.log  install.log.syslog
[root@datanode2 ~]# ls -a
.  ..  anaconda-ks.cfg  .bash_history  .bash_logout  .bash_profile  .bashrc  .cshrc  install.log  install.log.syslog  .oracle_jre_usage  .ssh  .tcshrc  .xauth9yJBa2
[root@datanode2 ~]# cd .ssh
[root@datanode2 .ssh]# ls
id_rsa  id_rsa.pub  known_hosts
[root@datanode2 .ssh]# ls -l
total 12
-rw-------. 1 root root 1671 Nov 25 23:28 id_rsa
-rw-r--r--. 1 root root  396 Nov 25 23:28 id_rsa.pub
-rw-r--r--. 1 root root  813 Nov 25 22:50 known_hosts


转到虚机192.168.115.132 slave/datanode2节点上以root权限重复上述步骤生成密钥；

[datanode2@datanode2 ~]$ pwd
/home/datanode2
[datanode2@datanode2 ~]$ ssh-keygen -t rsa
Generating public/private rsa key pair.
Enter file in which to save the key (/home/datanode2/.ssh/id_rsa):
Enter passphrase (empty for no passphrase):
Enter same passphrase again:
Your identification has been saved in /home/datanode2/.ssh/id_rsa.
Your public key has been saved in /home/datanode2/.ssh/id_rsa.pub.
The key fingerprint is:
b3:10:5c:18:5c:40:4c:4a:d0:00:26:0b:ec:b3:34:ed datanode2@datanode2
The key's randomart image is:
+--[ RSA 2048]----+
|=oo+.===o        |
|+o ..o+.         |
|o . . o          |
| = .   .         |
|. =   . S        |
| . E   . o       |
|        .        |
|                 |
|                 |
+-----------------+
[datanode2@datanode2 ~]$ cd /root/
bash: cd: /root/: Permission denied
[datanode2@datanode2 ~]$ ls -a
.              .bash_profile  .dbus      Downloads    .gconfd  .gstreamer-0.10  .icons    .nautilus          .pulse               .ssh         Videos
..             .bashrc        Desktop    .esd_auth    .gnome2  .gtk-bookmarks   .local    .oracle_jre_usage  .pulse-cookie        Templates    .viminfo
.bash_history  .cache         .dmrc      .fontconfig  .gnote   .gvfs            .mozilla  Pictures           .recently-used.xbel  .themes      .xsession-errors
.bash_logout   .config        Documents  .gconf       .gnupg   .ICEauthority    Music     Public             .spice-vdagent       .thumbnails  .xsession-errors.old
[datanode2@datanode2 ~]$ cd .ssh
[datanode2@datanode2 .ssh]$ ls
id_rsa  id_rsa.pub
[datanode2@datanode2 .ssh]$ ls -l
total 8
-rw-------. 1 datanode2 datanode2 1675 Nov 25 23:35 id_rsa
-rw-r--r--. 1 datanode2 datanode2  401 Nov 25 23:35 id_rsa.pub


将节点1（192.168.115.130/namenode）的id_rsa.pub文件分别拷贝到节点2和节点3的/root/.ssh目录下，并重命名为authorized_keys；

[root@namenode .ssh]# scp ./id_rsa.pub root@datanode1:/root/.ssh/authorized_keys
root@datanode1's password:
id_rsa.pub                                                                             100%  395     0.4KB/s   00:00
[root@namenode .ssh]# scp ./id_rsa.pub root@datanode2:/root/.ssh/authorized_keys
root@datanode2's password:
id_rsa.pub                                                                             100%  395     0.4KB/s   00:00
[root@namenode .ssh]# scp ./id_rsa.pub root@datanode2:/root/.ssh/authorized_keys
id_rsa.pub                                                                                                                                     100%  395     0.4KB/s   00:00


分别在节点2 和节点3 的对于目录下查看拷贝文件的属性；





验证是否生效，实现免密码登录；





以上仅仅只是实现了从namenode节点SSH免密码登录到datanode1节点和datanode2节点，因为datanode1节点和datanode2节点只保留了namenode节点的公钥，且上述步骤并不能使namenode节点免密码SSH登录到自身节点，见下图：



如果我们想要在3个节点间实现任意节点的免密码SSH登录并且可以免密码SSH登录到自身节点，首先我们需要造在namenode节点的/root/.ssh目录下创建authorized_keys文件，将其他节点的公钥拷贝到的authorized_keys文件中，从而实现任意节点间的免密码SSH登录。

以namenode节点为例实现自身的SSH免密码登录；

[root@namenode ~]# scp /root/.ssh/id_rsa.pub root@namenode:/root/.ssh/authorized_keys
root@namenode's password:
id_rsa.pub                                                                                                                                                                  100%  395     0.4KB/s   00:00
[root@namenode ~]# cd /root/
[root@namenode ~]# ls
anaconda-ks.cfg  Desktop  Documents  Downloads  install.log  install.log.syslog  Music  Pictures  Public  Templates  Videos
[root@namenode ~]# cd .ssh
[root@namenode .ssh]# ls
authorized_keys  id_rsa  id_rsa.pub  known_hosts
[root@namenode .ssh]# ls -l
total 16
-rw-r--r--. 1 root root  395 Nov 26 00:24 authorized_keys
-rw-------. 1 root root 1675 Nov 25 23:03 id_rsa
-rw-r--r--. 1 root root  395 Nov 25 23:03 id_rsa.pub
-rw-r--r--. 1 root root 2392 Nov 25 11:10 known_hosts
[root@namenode .ssh]# ssh namenode
Last login: Sat Nov 26 00:22:57 2016 from datanode2


使用vi authorized_keys命令编辑每个节点的authorized_keys文件，将缺少的节点公钥拷贝到该文件里，保存并退出；



验证任意节点的免密码自登陆及任意节点间的免密码SSH登录；

[root@namenode .ssh]# ssh namenode
Last login: Sat Nov 26 00:24:59 2016 from namenode
[root@namenode ~]# ssh datanode1
Last login: Sat Nov 26 00:34:16 2016 from namenode
[root@datanode1 ~]# ssh datanode2
Last login: Fri Nov 25 23:58:37 2016 from namenode
[root@datanode2 ~]# ssh datanode1
Last login: Sat Nov 26 00:48:14 2016 from namenode
[root@datanode1 ~]# ssh namenode
Last login: Sat Nov 26 00:48:02 2016 from namenode

通过以上步骤，即可实现了本集群中任意一台机器免密码SSH登录到另外一台机器；接下来，小编带你进入Hadoop的正式安装......

五、Hadoop1.2.1的安装
hadoop的安装一般是先在namenode节点上修改相关文件，然后将配置好的namenode节点上的hadoop文件夹向各节点复制；小编先是配置虚机192.168.115.130/namenode节点上的hadoop,然后向虚机92.168.115.131/datanode1节点和192.168.115.132/datanode2节点复制修改好的hadoop文件。

确保iptables,selinux等防火墙或访问控制机制已关闭

[root@namenode Desktop]# service iptables stop
iptables: Setting chains to policy ACCEPT: filter          [  OK  ]
iptables: Flushing firewall rules:                         [  OK  ]
iptables: Unloading modules:                               [  OK  ]


下载并解压到文件夹hadoop-1.2.1



cd /usr/local/hadoop-1.2.1/conf/         转到hadoop配置目录下 进行文件的配置

[tpf@namenode hadoop-1.2.1]$ cd conf
[tpf@namenode conf]$ ls
capacity-scheduler.xml  fair-scheduler.xml          hadoop-policy.xml  mapred-queue-acls.xml  slaves                  taskcontroller.cfg
configuration.xsl       hadoop-env.sh               hdfs-site.xml      mapred-site.xml        ssl-client.xml.example  task-log4j.properties
core-site.xml           hadoop-metrics2.properties  log4j.properties   masters                ssl-server.xml.example


修改hadoop-env.sh

# The java implementation to use.  Required.
export JAVA_HOME=/usr/local/jdk1.8.0_111


修改core-site.xml   写入如下信息，要注意，自己要在/usr/local/hadoop-1.2.1/ 目录下手动建立tmp目录，如没有配置hadoop.tmp.dir参数，此时系统默认的临时目录为：/tmp/hadoop-dfs。而这个目录在每次重启后都会被删掉，必须重新执行format才行，否则会出错，hdfs后面的ip号就是名称节点的ip,即namenode的ip,端口号默认9000,不用改动 ；

<configuration>
<property>
<name>fs.default.name</name>
<value>hdfs://namenode:9000</value>
</property>
<property>
<name>hadoop.tmp.dir</name>
<value>/usr/local/hadoop-1.2.1/tmp</value>
</property>
</configuration>


修改hdfs-site.xml 

设置数据备份数目，这里我们有有一个namenode，两个datanode，所以备份数目设置为2

<configuration>
<property>
<name>dfs.replication</name>
<value>2</value>
</property>
</configuration>


修改mapred-site.xml     设置map-reduce的作业跟踪器（jobtracker）所在节点，这里我们同样将其放置在namenode(192.168.115.130)节点上，端口号9001

<configuration>
<property>
<name>mapred.job.tracker</name>
<value>http://namenode:9001</value>
</property>
</configuration>


修改master   指定namenode所在节点；

namenode


修改slave   指定集群的datanode节点 ；

datanode1
datanode2


向各节点复制hadoop

[root@namenode local]# scp -r /usr/local/hadoop-1.2.1/ datanode1:/usr/local/
[root@namenode local]# scp -r /usr/local/hadoop-1.2.1/ datanode2:/usr/local/


执行文件系统格式化：bin/hadoop namenode -format,如果没有任何warning,error,fatal等并且最后出现，format successfully字样，则格式化成；

[root@namenode hadoop-1.2.1]# bin/hadoop namenode -format
16/11/26 04:30:08 INFO namenode.NameNode: STARTUP_MSG:
/************************************************************
STARTUP_MSG: Starting NameNode
STARTUP_MSG:   host = namenode/192.168.115.130
STARTUP_MSG:   args = [-format]
STARTUP_MSG:   version = 1.2.1
STARTUP_MSG:   build = https://svn.apache.org/repos/asf/hadoop/common/branches/branch-1.2 -r 1503152; compiled by 'mattf' on Mon Jul 22 15:23:09 PDT 2013
STARTUP_MSG:   java = 1.8.0_111
************************************************************/
16/11/26 04:30:09 INFO util.GSet: Computing capacity for map BlocksMap
16/11/26 04:30:09 INFO util.GSet: VM type       = 64-bit
16/11/26 04:30:09 INFO util.GSet: 2.0% max memory = 1013645312
16/11/26 04:30:09 INFO util.GSet: capacity      = 2^21 = 2097152 entries
16/11/26 04:30:09 INFO util.GSet: recommended=2097152, actual=2097152
16/11/26 04:30:09 INFO namenode.FSNamesystem: fsOwner=root
16/11/26 04:30:09 INFO namenode.FSNamesystem: supergroup=supergroup
16/11/26 04:30:09 INFO namenode.FSNamesystem: isPermissionEnabled=true
16/11/26 04:30:10 INFO namenode.FSNamesystem: dfs.block.invalidate.limit=100
16/11/26 04:30:10 INFO namenode.FSNamesystem: isAccessTokenEnabled=false accessKeyUpdateInterval=0 min(s), accessTokenLifetime=0 min(s)
16/11/26 04:30:10 INFO namenode.FSEditLog: dfs.namenode.edits.toleration.length = 0
16/11/26 04:30:10 INFO namenode.NameNode: Caching file names occuring more than 10 times
16/11/26 04:30:11 INFO common.Storage: Image file /usr/local/hadoop-1.2.1/tmp/dfs/name/current/fsimage of size 110 bytes saved in 0 seconds.
16/11/26 04:30:11 INFO namenode.FSEditLog: closing edit log: position=4, editlog=/usr/local/hadoop-1.2.1/tmp/dfs/name/current/edits
16/11/26 04:30:11 INFO namenode.FSEditLog: close success: truncate to 4, editlog=/usr/local/hadoop-1.2.1/tmp/dfs/name/current/edits
16/11/26 04:30:11 INFO common.Storage: Storage directory /usr/local/hadoop-1.2.1/tmp/dfs/name has been successfully formatted.
16/11/26 04:30:11 INFO namenode.NameNode: SHUTDOWN_MSG:
/************************************************************
SHUTDOWN_MSG: Shutting down NameNode at namenode/192.168.115.130
************************************************************/


启动hadoop

[root@namenode hadoop-1.2.1]# bin/start-all.sh
starting namenode, logging to /usr/local/hadoop-1.2.1/libexec/../logs/hadoop-tpf-namenode-namenode.out
datanode2: starting datanode, logging to /usr/local/hadoop-1.2.1/libexec/../logs/hadoop-root-datanode-datanode2.out
datanode1: starting datanode, logging to /usr/local/hadoop-1.2.1/libexec/../logs/hadoop-root-datanode-datanode1.out
namenode: starting secondarynamenode, logging to /usr/local/hadoop-1.2.1/libexec/../logs/hadoop-root-secondarynamenode-namenode.out
starting jobtracker, logging to /usr/local/hadoop-1.2.1/libexec/../logs/hadoop-tpf-jobtracker-namenode.out
datanode1: starting tasktracker, logging to /usr/local/hadoop-1.2.1/libexec/../logs/hadoop-root-tasktracker-datanode1.out
datanode2: starting tasktracker, logging to /usr/local/hadoop-1.2.1/libexec/../logs/hadoop-root-tasktracker-datanode2.out

namenode节点的启动日志：

[root@namenode hadoop-1.2.1]# cd logs/
[root@namenode logs]# ls
hadoop-root-secondarynamenode-namenode.log  hadoop-tpf-jobtracker-namenode.log  hadoop-tpf-namenode-namenode.log  history
hadoop-root-secondarynamenode-namenode.out  hadoop-tpf-jobtracker-namenode.out  hadoop-tpf-namenode-namenode.out

datanode1节点的启动日志：

[root@datanode1 logs]# ls
hadoop-root-datanode-datanode1.log  hadoop-root-datanode-datanode1.out  hadoop-root-tasktracker-datanode1.log  hadoop-root-tasktracker-datanode1.out

datanode2节点的启动日志：

[root@datanode2 hadoop-1.2.1]# cd logs/
[root@datanode2 logs]# ls
hadoop-root-datanode-datanode2.log  hadoop-root-datanode-datanode2.out  hadoop-root-tasktracker-datanode2.log  hadoop-root-tasktracker-datanode2.out


用jps检验各后台进程是否成功启动

[root@namenode hadoop-1.2.1]# jps
55553 SecondaryNameNode
55411 NameNode
55637 JobTracker
55737 Jps

[root@datanode1 hadoop-1.2.1]# jps
39219 Jps
39155 TaskTracker
39077 DataNode

[root@datanode2 hadoop-1.2.1]# jps
6641 DataNode
6814 Jps
6719 TaskTracker

第一次启动的时候，datanode1节点总是启动不了；最后找下来发现是由于datanode1的防火墙没关闭，阻止了相应的端口号。

[root@namenode hadoop-1.2.1]# bin/stop-all.sh
stopping jobtracker
datanode2: stopping tasktracker
datanode1: no tasktracker to stop
stopping namenode
datanode2: stopping datanode
datanode1: no datanode to stop
namenode: stopping secondarynamenode

[root@datanode1 logs]# jps
38824 Jps


六、集群测试
[root@namenode hadoop-1.2.1]# bin/hadoop fs -put /usr/local/input/ in
[root@namenode hadoop-1.2.1]# bin/hadoop fs -cat /usr/local/input/ in
cat: File does not exist: /usr/local/input
cat: File does not exist: /user/root/in
[root@namenode hadoop-1.2.1]# bin/hadoop fs -cat /usr/local/input/ ./in/*
cat: File does not exist: /usr/local/input
hello world
hello hadoop
[root@namenode hadoop-1.2.1]# bin/hadoop fs -cat /usr/local/input/ ./in
cat: File does not exist: /usr/local/input
cat: File does not exist: /user/root/in
[root@namenode hadoop-1.2.1]# bin/hadoop fs -ls ./in
Found 2 items
-rw-r--r--   2 root supergroup         12 2016-11-26 07:18 /user/root/in/text1.txt
-rw-r--r--   2 root supergroup         13 2016-11-26 07:18 /user/root/in/text2.txt
[root@namenode hadoop-1.2.1]# bin/hadoop fs -cat ./in/text1.txt
hello world
[root@namenode hadoop-1.2.1]# bin/hadoop fs -cat ./in/text2.txt
hello hadoop
[root@namenode hadoop-1.2.1]# ls
bin        c++          conf     docs                  hadoop-client-1.2.1.jar  hadoop-examples-1.2.1.jar     hadoop-test-1.2.1.jar   ivy      lib      LICENSE.txt  NOTICE.txt  sbin   src  webapps
build.xml  CHANGES.txt  contrib  hadoop-ant-1.2.1.jar  hadoop-core-1.2.1.jar    hadoop-minicluster-1.2.1.jar  hadoop-tools-1.2.1.jar  ivy.xml  libexec  logs         README.txt  share  tmp
[root@namenode hadoop-1.2.1]# bin/hadoop jar hadoop-examples-1.2.1.jar wordcount in out
16/11/26 07:24:35 INFO input.FileInputFormat: Total input paths to process : 2
16/11/26 07:24:35 INFO util.NativeCodeLoader: Loaded the native-hadoop library
16/11/26 07:24:35 WARN snappy.LoadSnappy: Snappy native library not loaded
16/11/26 07:24:36 INFO mapred.JobClient: Running job: job_201611260717_0001
16/11/26 07:24:37 INFO mapred.JobClient:  map 0% reduce 0%
16/11/26 07:24:49 INFO mapred.JobClient:  map 50% reduce 0%
16/11/26 07:24:52 INFO mapred.JobClient:  map 100% reduce 0%
16/11/26 07:25:03 INFO mapred.JobClient:  map 100% reduce 100%
16/11/26 07:25:06 INFO mapred.JobClient: Job complete: job_201611260717_0001
16/11/26 07:25:06 INFO mapred.JobClient: Counters: 29
16/11/26 07:25:06 INFO mapred.JobClient:   Map-Reduce Framework
16/11/26 07:25:06 INFO mapred.JobClient:     Spilled Records=8
16/11/26 07:25:06 INFO mapred.JobClient:     Map output materialized bytes=61
16/11/26 07:25:06 INFO mapred.JobClient:     Reduce input records=4
16/11/26 07:25:06 INFO mapred.JobClient:     Virtual memory (bytes) snapshot=5800710144
16/11/26 07:25:06 INFO mapred.JobClient:     Map input records=2
16/11/26 07:25:06 INFO mapred.JobClient:     SPLIT_RAW_BYTES=216
16/11/26 07:25:06 INFO mapred.JobClient:     Map output bytes=41
16/11/26 07:25:06 INFO mapred.JobClient:     Reduce shuffle bytes=61
16/11/26 07:25:06 INFO mapred.JobClient:     Physical memory (bytes) snapshot=418377728
16/11/26 07:25:06 INFO mapred.JobClient:     Reduce input groups=3
16/11/26 07:25:06 INFO mapred.JobClient:     Combine output records=4
16/11/26 07:25:06 INFO mapred.JobClient:     Reduce output records=3
16/11/26 07:25:06 INFO mapred.JobClient:     Map output records=4
16/11/26 07:25:06 INFO mapred.JobClient:     Combine input records=4
16/11/26 07:25:06 INFO mapred.JobClient:     CPU time spent (ms)=3400
16/11/26 07:25:06 INFO mapred.JobClient:     Total committed heap usage (bytes)=337780736
16/11/26 07:25:06 INFO mapred.JobClient:   File Input Format Counters
16/11/26 07:25:06 INFO mapred.JobClient:     Bytes Read=25
16/11/26 07:25:06 INFO mapred.JobClient:   FileSystemCounters
16/11/26 07:25:06 INFO mapred.JobClient:     HDFS_BYTES_READ=241
16/11/26 07:25:06 INFO mapred.JobClient:     FILE_BYTES_WRITTEN=173342
16/11/26 07:25:06 INFO mapred.JobClient:     FILE_BYTES_READ=55
16/11/26 07:25:06 INFO mapred.JobClient:     HDFS_BYTES_WRITTEN=25
16/11/26 07:25:06 INFO mapred.JobClient:   Job Counters
16/11/26 07:25:06 INFO mapred.JobClient:     Launched map tasks=2
16/11/26 07:25:06 INFO mapred.JobClient:     Launched reduce tasks=1
16/11/26 07:25:06 INFO mapred.JobClient:     SLOTS_MILLIS_REDUCES=12312
16/11/26 07:25:06 INFO mapred.JobClient:     Total time spent by all reduces waiting after reserving slots (ms)=0
16/11/26 07:25:06 INFO mapred.JobClient:     SLOTS_MILLIS_MAPS=20972
16/11/26 07:25:06 INFO mapred.JobClient:     Total time spent by all maps waiting after reserving slots (ms)=0
16/11/26 07:25:06 INFO mapred.JobClient:     Data-local map tasks=2
16/11/26 07:25:06 INFO mapred.JobClient:   File Output Format Counters
16/11/26 07:25:06 INFO mapred.JobClient:     Bytes Written=25
[root@namenode hadoop-1.2.1]# bin/hadoop fs -ls
Found 2 items
drwxr-xr-x   - root supergroup          0 2016-11-26 07:18 /user/root/in
drwxr-xr-x   - root supergroup          0 2016-11-26 07:25 /user/root/out
[root@namenode hadoop-1.2.1]# bin/hadoop fs -ls ./out
Found 3 items
-rw-r--r--   2 root supergroup          0 2016-11-26 07:25 /user/root/out/_SUCCESS
drwxr-xr-x   - root supergroup          0 2016-11-26 07:24 /user/root/out/_logs
-rw-r--r--   2 root supergroup         25 2016-11-26 07:24 /user/root/out/part-r-00000
[root@namenode hadoop-1.2.1]# bin/hadoop fs -cat ./out/part-r-00000
hadoop	1
hello	2
world	1


七、注意事项
确保关闭防火墙

#关闭:
service iptables stop
#查看:
service iptables status
#重启不启动:
chkconfig iptables off
#重启启动:
chkconfig iptables on

[INFO] Reactor Summary:
[INFO]
[INFO] Apache Hadoop Main ................................. SUCCESS [  01:05 h]
[INFO] Apache Hadoop Project POM .......................... SUCCESS [05:58 min]
[INFO] Apache Hadoop Annotations .......................... SUCCESS [03:01 min]
[INFO] Apache Hadoop Assemblies ........................... SUCCESS [  0.598 s]
[INFO] Apache Hadoop Project Dist POM ..................... SUCCESS [02:07 min]
[INFO] Apache Hadoop Maven Plugins ........................ FAILURE [02:08 min]
[INFO] Apache Hadoop MiniKDC .............................. SKIPPED
[INFO] Apache Hadoop Auth ................................. SKIPPED
[INFO] Apache Hadoop Auth Examples ........................ SKIPPED
[INFO] Apache Hadoop Common ............................... SKIPPED
[INFO] Apache Hadoop NFS .................................. SKIPPED
[INFO] Apache Hadoop Common Project ....................... SKIPPED
[INFO] Apache Hadoop HDFS ................................. SKIPPED
[INFO] Apache Hadoop HttpFS ............................... SKIPPED
[INFO] Apache Hadoop HDFS BookKeeper Journal .............. SKIPPED
[INFO] Apache Hadoop HDFS-NFS ............................. SKIPPED
[INFO] Apache Hadoop HDFS Project ......................... SKIPPED
[INFO] hadoop-yarn ........................................ SKIPPED
[INFO] hadoop-yarn-api .................................... SKIPPED
[INFO] hadoop-yarn-common ................................. SKIPPED
[INFO] hadoop-yarn-server ................................. SKIPPED
[INFO] hadoop-yarn-server-common .......................... SKIPPED
[INFO] hadoop-yarn-server-nodemanager ..................... SKIPPED
[INFO] hadoop-yarn-server-web-proxy ....................... SKIPPED
[INFO] hadoop-yarn-server-resourcemanager ................. SKIPPED
[INFO] hadoop-yarn-server-tests ........................... SKIPPED
[INFO] hadoop-yarn-client ................................. SKIPPED
[INFO] hadoop-yarn-applications ........................... SKIPPED
[INFO] hadoop-yarn-applications-distributedshell .......... SKIPPED
[INFO] hadoop-yarn-applications-unmanaged-am-launcher ..... SKIPPED
[INFO] hadoop-yarn-site ................................... SKIPPED
[INFO] hadoop-yarn-project ................................ SKIPPED
[INFO] hadoop-mapreduce-client ............................ SKIPPED
[INFO] hadoop-mapreduce-client-core ....................... SKIPPED
[INFO] hadoop-mapreduce-client-common ..................... SKIPPED
[INFO] hadoop-mapreduce-client-shuffle .................... SKIPPED
[INFO] hadoop-mapreduce-client-app ........................ SKIPPED
[INFO] hadoop-mapreduce-client-hs ......................... SKIPPED
[INFO] hadoop-mapreduce-client-jobclient .................. SKIPPED
[INFO] hadoop-mapreduce-client-hs-plugins ................. SKIPPED
[INFO] Apache Hadoop MapReduce Examples ................... SKIPPED
[INFO] hadoop-mapreduce ................................... SKIPPED
[INFO] Apache Hadoop MapReduce Streaming .................. SKIPPED
[INFO] Apache Hadoop Distributed Copy ..................... SKIPPED
[INFO] Apache Hadoop Archives ............................. SKIPPED
[INFO] Apache Hadoop Rumen ................................ SKIPPED
[INFO] Apache Hadoop Gridmix .............................. SKIPPED
[INFO] Apache Hadoop Data Join ............................ SKIPPED
[INFO] Apache Hadoop Extras ............................... SKIPPED
[INFO] Apache Hadoop Pipes ................................ SKIPPED
[INFO] Apache Hadoop OpenStack support .................... SKIPPED
[INFO] Apache Hadoop Client ............................... SKIPPED
[INFO] Apache Hadoop Mini-Cluster ......................... SKIPPED
[INFO] Apache Hadoop Scheduler Load Simulator ............. SKIPPED
[INFO] Apache Hadoop Tools Dist ........................... SKIPPED
[INFO] Apache Hadoop Tools ................................ SKIPPED
[INFO] Apache Hadoop Distribution ......................... SKIPPED
[INFO] ------------------------------------------------------------------------
[INFO] BUILD FAILURE
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 01:51 h
[INFO] Finished at: 2016-11-27T06:31:52-08:00
[INFO] Final Memory: 44M/106M
[INFO] ------------------------------------------------------------------------
[ERROR] Failed to execute goal org.apache.maven.plugins:maven-javadoc-plugin:2.8.1:jar (module-javadocs) on project hadoop-maven-plugins: MavenReportException: Error while creating archive:
[ERROR] Exit code: 1 - /home/grid/release-2.3.0/hadoop-maven-plugins/src/main/java/org/apache/hadoop/maven/plugin/util/Exec.java:47: error: unknown tag: String
[ERROR] * @param command List<String> containing command and all arguments
[ERROR] ^
[ERROR] /home/grid/release-2.3.0/hadoop-maven-plugins/src/main/java/org/apache/hadoop/maven/plugin/util/Exec.java:48: error: unknown tag: String
[ERROR] * @param output List<String> in/out parameter to receive command output
[ERROR] ^
[ERROR] /home/grid/release-2.3.0/hadoop-maven-plugins/src/main/java/org/apache/hadoop/maven/plugin/util/FileSetUtils.java:52: error: unknown tag: File
[ERROR] * @return List<File> containing every element of the FileSet as a File
[ERROR] ^
[ERROR]
[ERROR] Command line was: /usr/local/jdk1.8.0_111/jre/../bin/javadoc @options @packages
[ERROR]
[ERROR] Refer to the generated Javadoc files in '/home/grid/release-2.3.0/hadoop-maven-plugins/target' dir.
[ERROR] -> [Help 1]
[ERROR]
[ERROR] To see the full stack trace of the errors, re-run Maven with the -e switch.
[ERROR] Re-run Maven using the -X switch to enable full debug logging.
[ERROR]
[ERROR] For more information about the errors and possible solutions, please read the following articles:
[ERROR] [Help 1] http://cwiki.apache.org/confluence/display/MAVEN/MojoExecutionException [ERROR]
[ERROR] After correcting the problems, you can resume the build with the command

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