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Hadoop2.2.0完全分布式集群平台安装与设置

  如果你想搭建伪分布式Hadoop平台,请参见本博客《在Fedora上部署Hadoop2.2.0伪分布式平台》
  经过好多天的各种折腾,终于在几台电脑里面配置好了Hadoop2.2.0分布式系统,现在总结一下如何配置。

  前提条件:
  (1)、首先在每台Linux电脑上面安装好JDK6或其以上版本,并设置好JAVA_HOME等,测试一下java、javac、jps等命令是否可以在终端使用,如何配置JDK这里就不说了;
  (2)、在每台Linux上安装好SSH,如何安装请参加《Linux平台下安装SSH》。后面会说如何配置SSH无密码登录。

  有了上面的前提条件之后,我们接下来就可以进行安装Hadoop分布式平台了。步骤如下:

  1、先设定电脑的IP为静态地址:

  由于各个Linux发行版本静态IP的设置不一样,这里将介绍CentOS、Ubunt、Fedora 19静态IP的设置步骤:
  (1)、CentOS静态IP地址设置步骤如下:

[wyp@wyp hadoop]$ sudo vim /etc/sysconfig/network-scripts/ifcfg-eth0

在里面添加下面语句:

IPADDR=192.168.142.139
NETMASK=255.255.255.0
NETWORK=192.168.0.0

里面的IPADDR地址设置你想要的,我这里是192.168.142.139。
设置好后,需要让IP地址生效,运行下面命令:

[wyp@wyp hadoop]$ sudo service network restart 
Shutting down interface eth0:  Device state: 3 (disconnected)
                                                           [  OK  ]
Shutting down loopback interface:                          [  OK  ]
Bringing up loopback interface:                            [  OK  ]
Bringing up interface eth0:  Active connection state: activated
Active connection path: /org/freedesktop/NetworkManager/ActiveConnection/7
                                                           [  OK  ]
[wyp@wyp hadoop]$ 

然后运行ifconfig检验一下设置是否生效:

[wyp@wyp hadoop]$ ifconfig
eth0      Link encap:Ethernet  HWaddr 00:0C:29:9F:FB:C0  
          inet addr:192.168.142.139  Bcast:192.168.142.255  Mask:255.255.255.0
          inet6 addr: fe80::20c:29ff:fe9f:fbc0/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:389330 errors:0 dropped:0 overruns:0 frame:0
          TX packets:171679 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:473612019 (451.6 MiB)  TX bytes:30110196 (28.7 MiB)

lo        Link encap:Local Loopback  
          inet addr:127.0.0.1  Mask:255.0.0.0
          inet6 addr: ::1/128 Scope:Host
          UP LOOPBACK RUNNING  MTU:16436  Metric:1
          RX packets:80221 errors:0 dropped:0 overruns:0 frame:0
          TX packets:80221 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0 
          RX bytes:1051174395 (1002.4 MiB)  TX bytes:1051174395 (1002.4 MiB)

[wyp@wyp hadoop]$ 

可见IP地址已经设置为192.168.142.139了!
  (2)、Ubuntu静态IP地址设置步骤如下:

wyp@node1:~$ sudo vim /etc/network/interfaces

在里面添加:

auto eth0
iface eth0 inet static
address 192.168.142.140
netmask 255.255.255.0
gateway 192.168.142.1

同样需要让IP地址生效:

wyp@node1:~$ sudo /etc/init.d/networking restart

同样也是输入ifconfig来检验IP设置是否生效,这里就不说了。
  (3)、Fedora 19静态IP地址设置步骤如下(Fedora其他版本的静态IP设置和19版本不一样,这里就不给出了):

[wyp@wyp network-scripts]$ sudo vim /etc/sysconfig/network-scripts/ifcfg-ens33

在里面添加:

IPADDR0=192.168.142.138
NETMASK0=255.255.255.0
GATEWAY0=192.168.142.0

设置好后,需要让IP地址生效,运行下面命令:

[wyp@wyp network-scripts]$ sudo service network restart 
Restarting network (via systemctl):                        [  确定  ]

同样也是输入ifconfig来检验IP设置是否生效,这里就不说了。

  2、设置各个主机的hostname

  在步骤1中,我分别配置了CentOS、Ubuntu以及Fedora三台主机,我打算用它们作为集群中的电脑,其中Fedora主机作为master,其余的两台电脑作为slave。这步将说说如何修改这三台电脑的hostname:
  (1)、Fedora19 设置hostname步骤如下:

[wyp@wyp network-scripts]$ sudo hostnamectl set-hostname master

查看设置是否生效,运行下面命令

[wyp@wyp network-scripts]$ hostname
master

  (2)、Ubuntu设置hostname步骤如下:

wyp@node1:~$ sudo vim /etc/hostname

在里面添加自己需要取的hostname,我这里是取node1。
查看设置是否生效,运行下面命令

wyp@node1:~$ hostname
node1

  (3)、CentOS设置hostname步骤如下:

[wyp@node network-scripts]$ sudo vim /etc/sysconfig/network

将里面的HOSTNAME修改为你想要的hostname,我这里是取node

HOSTNAME=node

查看设置是否生效,运行下面命令

[wyp@node network-scripts]$ hostname
node

  3、在以上三台电脑的/etc/hosts添加以下配置:

[wyp@master ~]$ sudo vim /etc/hosts

在里面添加以下语句

192.168.142.138 master
192.168.142.139 node
192.168.142.140 node1

其实就是上面三台电脑的静态IP地址和其hostname的对应关系。检验是否修改生效,可以用ping来查看:

[wyp@master ~]$ ping node
PING node (192.168.142.139) 56(84) bytes of data.
64 bytes from node (192.168.142.139): icmp_seq=1 ttl=64 time=0.541 ms
64 bytes from node (192.168.142.139): icmp_seq=2 ttl=64 time=0.220 ms
^C
--- node ping statistics ---
2 packets transmitted, 2 received, 0% packet loss, time 1000ms
rtt min/avg/max/mdev = 0.220/0.380/0.541/0.161 ms
[wyp@master ~]$ 

如果上面的命令可以ping通,说明设置生效了。

  4、设置SSH无密码登陆

  在本博客里面已经介绍了如何安装SSH(《Linux平台下安装SSH》),和怎么设置SSH无密码登陆(《Ubuntu和CentOS如何配置SSH使得无密码登陆》),这里主要是想说一下需要注意的事项,首先在master主机上面设置好了SSH无密码登陆之后,然后将生成的id_dsa.pub文件拷贝到node和node1上面去,可以运行下面的命令:

[wyp@localhost ~]$ cat /home/wyp/.ssh/id_dsa.pub |    \
ssh wyp@192.168.142.139 'cat - >> ~/.ssh/authorized_keys'

  要确保192.168.142.139主机的SSH服务是运行的。wyp@192.168.142.139的wyp是你需要登录192.168.142.139主机的用户名。同样,你也可以用上面类似的命令将id_dsa.pub拷贝到192.168.142.140主机上面去。
  当然,你也可以用scp命令将文件拷贝到相应的主机:

[wyp@master Documents]$ scp /home/wyp/.ssh/id_dsa.pub     \
wyp@192.168.142.139:~/.ssh/authorized_keys

检验是否可以从master无密码登录node和node1,可以用下面的命令:

[wyp@master Documents]$ ssh node
The authenticity of host 'node (192.168.142.139)' can't be established.
RSA key fingerprint is ae:99:43:f0:cf:c6:a9:82:6c:93:a1:65:54:70:a6:97.
Are you sure you want to continue connecting (yes/no)? yes
Warning: Permanently added 'node,192.168.142.139' (RSA) 
to the list of known hosts.
Last login: Wed Nov  6 14:54:55 2013 from master
[wyp@node ~]$ 

  第一次运行上面的命令会出现上述信息。上面[wyp@node ~]已经暗示了我们成功从master无密码登录node;如果在登陆过程中出现了需要输入密码才能登录node,说明SSH无密码登录没成功,一般都是文件权限的问题,解决方法请参照《Ubuntu和CentOS如何配置SSH使得无密码登陆》

  5、下载好Hadoop,这里用到的是hadoop-2.2.0.tar.gz,你可以用下面的命令去下载:
  下面的操作都是在master机器上进行的。

[wyp@wyp /home]$ mkdir /home/wyp/Downloads/hadoop
[wyp@wyp /home]$ cd /home/wyp/Downloads/hadoop
[wyp@wyp hadoop]$ wget \
http://mirror.bit.edu.cn/apache/hadoop/common/hadoop-2.2.0/hadoop-2.2.0.tar.gz

运行完上面的命令之后,hadoop-2.2.0.tar.gz文件将会保存在/home/wyp/Downloads/hadoop里面,请解压它

[wyp@wyp hadoop]$ tar- zxvf hadoop-2.2.0.tar.gz

之后将会在hadoop文件夹下面生成hadoop-2.2.0文件夹,运行下面的命令

[wyp@wyp hadoop]$ cd hadoop-2.2.0
[wyp@wyp hadoop-2.2.0]$ ls -l
total 56
drwxr-xr-x. 2 wyp wyp  4096 Oct  7 14:38 bin
drwxr-xr-x. 3 wyp wyp  4096 Oct  7 14:38 etc
drwxr-xr-x. 2 wyp wyp  4096 Oct  7 14:38 include
drwxr-xr-x. 3 wyp wyp  4096 Oct  7 14:38 lib
drwxr-xr-x. 2 wyp wyp  4096 Oct  7 14:38 libexec
-rw-r--r--. 1 wyp wyp 15164 Oct  7 14:46 LICENSE.txt
drwxrwxr-x. 3 wyp wyp  4096 Oct 28 14:38 logs
-rw-r--r--. 1 wyp wyp   101 Oct  7 14:46 NOTICE.txt
-rw-r--r--. 1 wyp wyp  1366 Oct  7 14:46 README.txt
drwxr-xr-x. 2 wyp wyp  4096 Oct 28 12:37 sbin
drwxr-xr-x. 4 wyp wyp  4096 Oct  7 14:38 share

显示出刚刚解压文件的文件夹。

  6、配置Hadoop的环境变量

[wyp@wyp hadoop]$ sudo vim /etc/profile
 
在/etc/profile文件的末尾加上以下配置
 
export HADOOP_DEV_HOME=/home/wyp/Downloads/hadoop/hadoop-2.2.0
export PATH=$PATH:$HADOOP_DEV_HOME/bin
export PATH=$PATH:$HADOOP_DEV_HOME/sbin
export HADOOP_MAPARED_HOME=${HADOOP_DEV_HOME}
export HADOOP_COMMON_HOME=${HADOOP_DEV_HOME}
export HADOOP_HDFS_HOME=${HADOOP_DEV_HOME}
export YARN_HOME=${HADOOP_DEV_HOME}
export HADOOP_CONF_DIR=${HADOOP_DEV_HOME}/etc/hadoop

然后按:wq保存。为了让刚刚的设置生效,运行下面的命令

[wyp@wyp hadoop]$ sudo source /etc/profile

在终端输入hadoop命令查看Hadoop的环境变量是否生效:

[wyp@node ~]$ hadoop
Usage: hadoop [--config confdir] COMMAND
       where COMMAND is one of:
  fs                   run a generic filesystem user client
  version              print the version
  jar <jar>            run a jar file
  checknative [-a|-h]  check native hadoop and compression libraries 
                                                availability
  distcp <srcurl> <desturl> copy file or directories recursively
  archive -archiveName NAME -p <parent path> <src>* <dest> create 
                                             a hadoop archive
  classpath            prints the class path needed to get the
                       Hadoop jar and the required libraries
  daemonlog            get/set the log level for each daemon
 or
  CLASSNAME            run the class named CLASSNAME

Most commands print help when invoked w/o parameters.
[wyp@node ~]$ 

如果显示上面的信息,说明环境变量生效了,如果显示不了,重启一下电脑再试试。

  7、修改Hadoop的配置文件

修改Hadoop的hadoop-env.sh配置文件,设置jdk所在的路径:

[wyp@wyp hadoop]$ vim etc/hadoop/hadoop-env.sh
 
在里面找到JAVA_HOME,并将它的值设置为你电脑jdk所在的绝对路径
 
# The java implementation to use.
export JAVA_HOME=/home/wyp/Downloads/jdk1.7.0_45

依次修改core-site.xml、yarn-site.xml、mapred-site.xml和hdfs-site.xml配置文件

----------------core-site.xml
<property>
  <name>fs.default.name</name>
  <value>hdfs://master:8020</value>
  <final>true</final>
</property>
<property>
  <name>hadoop.tmp.dir</name>
  <value>/home/wyp/cloud/tmp/hadoop2.0</value>
</property>
 
------------------------- yarn-site.xml
<property>
  <name>yarn.resourcemanager.address</name>
  <value>master:8032</value>
</property>

<property>
  <name>yarn.resourcemanager.scheduler.address</name>
  <value>master:8030</value>
</property>

<property>
  <name>yarn.resourcemanager.resource-tracker.address</name>
  <value>master:8031</value>
</property>

<property>
  <name>yarn.resourcemanager.admin.address</name>
  <value>master:8033</value>
</property>

<property>
  <name>yarn.resourcemanager.webapp.address</name>
  <value>master:8088</value>
</property>

<property> 
    <name>yarn.nodemanager.aux-services</name> 
    <value>mapreduce_shuffle</value> 
</property> 
 
<property> 
    <name>yarn.nodemanager.aux-services.mapreduce.shuffle.class</name> 
    <value>org.apache.hadoop.mapred.ShuffleHandler</value> 
</property> 
 
------------------------ mapred-site.xml
<property> 
    <name>mapreduce.framework.name</name> 
    <value>yarn</value> 
</property> 
 
<property> 
    <name>mapred.system.dir</name> 
    <value>file:/hadoop/mapred/system/</value> 
    <final>true</final> 
</property> 
 
<property> 
    <name>mapred.local.dir</name> 
    <value>file:/opt/cloud/hadoop_space/mapred/local</value> 
    <final>true</final> 
</property> 
 
----------- hdfs-site.xml  
<property>
    <name>dfs.namenode.name.dir</name>
    <value>file:/opt/cloud/hadoop_space/dfs/name</value>
    <final>true</final>
</property>
 
<property>
    <name>dfs.datanode.data.dir</name>
    <value>file:/opt/cloud/hadoop_space/dfs/data</value>
    <description>Determines where on the local 
      filesystem an DFS data node should store its blocks. 
      If this is a comma-delimited list of directories, 
      then data will be stored in all named 
      directories, typically on different devices. 
      Directories that do not exist are ignored. 
    </description>
    <final>true</final>
</property>
<property>
    <name>dfs.replication</name>
    <value>1</value>
</property>
 
<property>
    <name>dfs.permissions</name>
    <value>false</value>
</property>

配置好Hadoop的相关东西之后,请将hadoop-2.2.0整个文件夹分别拷贝到node和node1主机上面去,设置都不需要改!

  8、关掉master、node和node1的防火墙

如果在node上启动nodemanager,遇到java.net.NoRouteToHostException异常

java.net.NoRouteToHostException: No Route to Host from  
localhost.localdomain/192.168.142.139 to 192.168.142.138:8031 
failed on socket timeout exception: java.net.NoRouteToHostException: 
No route to host; For more details see: 
 http://wiki.apache.org/hadoop/NoRouteToHost

        ..................省略了好多东西

Caused by: java.net.NoRouteToHostException: No route to host
        at sun.nio.ch.SocketChannelImpl.checkConnect(Native Method)

        ..................省略了好多东西

        at org.apache.hadoop.ipc.Client.getConnection(Client.java:1399)
        at org.apache.hadoop.ipc.Client.call(Client.java:1318)
        ... 19 more

说明了没有关闭防火墙,各个linux平台关闭防火墙的方法不一样,这里也分享一下:
  (1)、对于ubuntu关闭防火墙

可以运行:ufw disable
如果你要防火墙可以运行: apt-get remove iptables

  (2)、对于fedora关闭防火墙可以运行:

[wyp@wyp hadoop]$  sudo systemctl stop firewalld.service
[wyp@wyp hadoop]$  sudo systemctl disable firewalld.service

  9、查看Hadoop是否运行成功

  首先在master上面格式化一下HDFS,如下命令

[wyp@wyp hadoop]$  cd $hadoop_home
[wyp@wyp hadoop-2.2.0]$  hdfs namenode -format
13/10/28 16:47:33 INFO namenode.NameNode: STARTUP_MSG: 
/************************************************************
 
..............此处省略好多文字......................
 
************************************************************/
13/10/28 16:47:33 INFO namenode.NameNode: registered UNIX signal 
handlers for [TERM, HUP, INT]
Formatting using clusterid: CID-9931f367-92d3-4693-a706-d83e120cacd6
13/10/28 16:47:34 INFO namenode.HostFileManager: read includes:
HostSet(
)
13/10/28 16:47:34 INFO namenode.HostFileManager: read excludes:
HostSet(
)
 
..............此处也省略好多文字......................
 
13/10/28 16:47:38 INFO util.ExitUtil: Exiting with status 0
13/10/28 16:47:38 INFO namenode.NameNode: SHUTDOWN_MSG: 
/************************************************************
SHUTDOWN_MSG: Shutting down NameNode at wyp/192.168.142.138
************************************************************/
[wyp@wyp hadoop-2.2.0]$ 

在master中启动 namenode 和 resourcemanager

[wyp@wyp hadoop-2.2.0]$ sbin/hadoop-daemon.sh start namenode
[wyp@wyp hadoop-2.2.0]$ sbin/yarn-daemon.sh start resourcemanager

在node和node1中启动datanode 和 nodemanager

[wyp@wyp hadoop-2.2.0]$ sbin/hadoop-daemon.sh start datanode
[wyp@wyp hadoop-2.2.0]$ sbin/yarn-daemon.sh start nodemanager

检查Hadoop集群是否安装好了,在master上面运行jps,如果有NameNode、ResourceManager二个进程,说明master安装好了。

[wyp@master hadoop]$ jps
2016 NameNode
2602 ResourceManager

在node(node1)上面运行jps,如果有DataNode、NodeManager二个进程,说明node(node1)安装好了。

[wyp@node network-scripts]$ jps
7889 DataNode
7979 NodeManager
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(6)个小伙伴在吐槽
  1. 看完有不明白的地方想问楼主:并没有发现关于两个datanode的配置信息,那namenode是怎么找到datanode的?
    lazi2014-11-23 22:38 回复
    •   首先不是namenode去主动找datanode的,因为namenode怎么可能集群中可能有哪些datanode呢?而且当你加子节点的时候,namenode是不知道的。  datanode会从core-site.xml文件中找fs.default.name,通过这个地址可以主动找到namenode。
      w3970907702014-11-23 23:54 回复
  2. 在使用命令 hdfs dfsadmin -report打印hdfs信息,出现下面问题:Cluster SummarySecurity is OFF1 files and directories, 0 blocks = 1 total.Heap Memory used 65.70 MB is 57% of Commited Heap Memory 115.25 MB. Max Heap Memory is 889 MB.Non Heap Memory used 15.70 MB is 58% of Commited Non Heap Memory 26.75 MB. Max Non Heap Memory is 112 MB.Configured Capacity : 0 BDFS Used : 0 BNon DFS Used : 0 BDFS Remaining : 0 BDFS Used% : 100.00%DFS Remaining% : 0.00%Block Pool Used : 0 BBlock Pool Used% : 100.00%DataNodes usages : Min % Median % Max % stdev % 0.00% 0.00% 0.00% 0.00%Live Nodes : 0 (Decommissioned: 0)Dead Nodes : 0 (Decommissioned: 0)Decommissioning Nodes : 0Number of Under-Replicated Blocks : 0There are no datanodes in the cluster.HTTP ERROR 500Problem accessing /nn_browsedfscontent.jsp. Reason: Can't browse the DFS since there are no live nodes available to redirect to.Caused by:java.io.IOException: Can't browse the DFS since there are no live nodes available to redirect to.at org.apache.hadoop.hdfs.server.namenode.NamenodeJspHelper.redirectToRandomDataNode(NamenodeJspHelper.java:646)at org.apache.hadoop.hdfs.server.namenode.nn_005fbrowsedfscontent_jsp._jspService(nn_005fbrowsedfscontent_jsp.java:70)at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:98)at javax.servlet.http.HttpServlet.service(HttpServlet.java:820)at org.mortbay.jetty.servlet.ServletHolder.handle(ServletHolder.java:511)at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1221)at org.apache.hadoop.http.lib.StaticUserWebFilter$StaticUserFilter.doFilter(StaticUserWebFilter.java:109)at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1212)at org.apache.hadoop.http.HttpServer$QuotingInputFilter.doFilter(HttpServer.java:1081)at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1212)at org.apache.hadoop.http.NoCacheFilter.doFilter(NoCacheFilter.java:45)at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1212)at org.apache.hadoop.http.NoCacheFilter.doFilter(NoCacheFilter.java:45)at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1212)at org.mortbay.jetty.servlet.ServletHandler.handle(ServletHandler.java:399)at org.mortbay.jetty.security.SecurityHandler.handle(SecurityHandler.java:216)at org.mortbay.jetty.servlet.SessionHandler.handle(SessionHandler.java:182)at org.mortbay.jetty.handler.ContextHandler.handle(ContextHandler.java:766)at org.mortbay.jetty.webapp.WebAppContext.handle(WebAppContext.java:450)at org.mortbay.jetty.handler.ContextHandlerCollection.handle(ContextHandlerCollection.java:230)at org.mortbay.jetty.handler.HandlerWrapper.handle(HandlerWrapper.java:152)at org.mortbay.jetty.Server.handle(Server.java:326)at org.mortbay.jetty.HttpConnection.handleRequest(HttpConnection.java:542)at org.mortbay.jetty.HttpConnection$RequestHandler.headerComplete(HttpConnection.java:928)at org.mortbay.jetty.HttpParser.parseNext(HttpParser.java:549)at org.mortbay.jetty.HttpParser.parseAvailable(HttpParser.java:212)at org.mortbay.jetty.HttpConnection.handle(HttpConnection.java:404)at org.mortbay.io.nio.SelectChannelEndPoint.run(SelectChannelEndPoint.java:410)at org.mortbay.thread.QueuedThreadPool$PoolThread.run(QueuedThreadPool.java:582)
    海阔天空2014-06-08 23:25 回复
    • Can’t browse the DFS since there are no live nodes available to redirect to.是不是你的datanode节点没有起来?看看有什么错误?
      w3970907702014-06-11 10:31 回复
  3. [code lang="JAVA"]<property> <name>mapred.system.dir</name> <value>file:/hadoop/mapred/system/</value> <final>true</final> </property> <property> <name>mapred.local.dir</name> <value>file:/opt/cloud/hadoop_space/mapred/local</value> <final>true</final> </property> [/code]请问file:/opt/cloud/hadoop_space/mapred/local 是什么意思,目录是如何设置的,有什么要求,谢谢!
    wghost2013-11-07 22:34 回复
    • mapred.system.dir:Path on the HDFS where where the MapReduce framework stores system files e.g. /hadoop/mapred/system/. This is in the default filesystem (HDFS) and must be accessible from both the server and client machines.mapred.local.dir :Comma-separated list of paths on the local filesystem where temporary MapReduce data is written.这是从Hadoop官网找到的,应该可以理解吧。
      w3970907702013-11-07 22:54 回复