hadoop2.7.1安装和部署

操作系统：Red Hat Enterprise Linux Server release 6.2 (Santiago)

hadoop2.7.1

三台redhat linux主机，ip分别为10.204.16.57-59，59为master，57、58为slave，

jdk版本为jdk-7u79-linux-x64.tar

一、环境准备

1、配置主机域名

设置主机名

配置hosts文件：vim /etc/hosts

在文件末添加内容如下：
10.204.16.59 master
10.204.16.58 slave8
10.204.16.57 slave7

2、设置ssh无密登录

1）在/home/bob下新建.ssh文件夹：mkdir .ssh

2）修改.ssh权限（关闭组和其他权限，否则ssh还需输密码）：chmod 700 .ssh

3）生成无密公钥和私钥：ssh-keygen -t rsa -P ''

　　让选择保存密钥的文件路径，回车直接用默认即可。

　　命令与结果如下：

　　

[bob@localhost ~]$ ssh-keygen -t rsa -P ''
Generating public/private rsa key pair.
Enter file in which to save the key (/home/bob/.ssh/id_rsa):
Your identification has been saved in /home/bob/.ssh/id_rsa.
Your public key has been saved in /home/bob/.ssh/id_rsa.pub.
The key fingerprint is:
:f1:5f:::4c::fa:a7::4e::a5:c0:4f: bob@localhost.localdomain
The key's randomart image is:
+--[ RSA ]----+
|        .  ..=*++|
|         o  E++oo|
|        . .  o+ o|
|         . . ..o.|
|        S   .   =|
|         .     =.|
|              o .|
|             .   |
|                 |
+-----------------+

4）用root用户修改ssh配置，启用RSA认证：vim /etc/ssh/sshd_config，去掉以下三项行首的‘#’，编辑后内容如下：

RSAAuthentication yes # 启用 RSA 认证

PubkeyAuthentication yes # 启用公钥私钥配对认证方式

AuthorizedKeysFile .ssh/authorized_keys # 公钥文件路径

5）导入公钥至认证文件：cat id_rsa.pub >> authorized_keys

6）设置认证文件权限（关闭组和其他权限，否则ssh还需输密码）：chmod 600 authorized_keys

7）重启sshd服务： service sshd restart

8）测试本机ssh无密登录是否成功：ssh bob@master

　　第一次会有确认提示，输入yes即可。

　　Last login: Tue Aug 25 14:43:51 2015 from 10.204.105.165
　　[bob@master ~]$ exit
　　logout

9）将master的/home/bob/.ssh文件夹传送至slave7、slave8，分别进行设置（生成密钥，将公钥追加至authorized_keys文件）。

　　传送命令： scp -r .ssh bob@slave7:~

　　测试master至slave7、slave8的ssh无密登录（bob用户），成功则进行后续步骤，否则检查以上步骤。

3、安装jdk

解压安装包：tar -xzvf jdk-7u79-linux-x64.tar.gz，解压文件路径/usr/bob/jdk1.7.0_79

root用户登录，设置环境变量：vim /etc/profile

结尾加入以下：

#set java and hadoop envs
export JAVA_HOME=/usr/bob/jdk1.7.0_79
export PATH=$JAVA_HOME/bin:$PATH:.
export CLASSPATH=$JAVA_HOME/jre/lib:.
export HADOOP_HOME=/usr/bob/hadoop-2.7.1
export PATH=$PATH:$HADOOP_HOME/bin

验证jdk是否按照成功：运行java或javac，成功则继续，否则检查以上步骤。

二、安装和设置hadoop

1）解压hadoop-2.7.1.tar.gz文件：tar -xzvf hadoop-2.7.1.tar.gz

解压后文件为hadoop-2.7.1，查看文件内容如下：

[bob@master bob]$ ls -la hadoop-2.7.1
total 60
drwxr-x---  9 bob bob  4096 Jun 29 14:15 .
drwxr-x---. 5 bob bob  4096 Aug 25 15:15 ..
drwxr-x---  2 bob bob  4096 Jun 29 14:15 bin
drwxr-x---  3 bob bob  4096 Jun 29 14:15 etc
drwxr-x---  2 bob bob  4096 Jun 29 14:15 include
drwxr-x---  3 bob bob  4096 Jun 29 14:15 lib
drwxr-x---  2 bob bob  4096 Jun 29 14:15 libexec
-rw-r-----  1 bob bob 15429 Jun 29 14:15 LICENSE.txt
-rw-r-----  1 bob bob   101 Jun 29 14:15 NOTICE.txt
-rw-r-----  1 bob bob  1366 Jun 29 14:15 README.txt
drwxr-x---  2 bob bob  4096 Jun 29 14:15 sbin
drwxr-x---  4 bob bob  4096 Jun 29 14:15 share

2）配置参数：涉及以下四个文件

core-site.xml

<?xml version="1.0" encoding="UTF-8"?>
<?xml-stylesheet type="text/xsl" href="configuration.xsl"?>
<!--
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License. See accompanying LICENSE file.
-->

<!-- Put site-specific property overrides in this file. -->

<configuration>

<property>
<name>fs.defaultFS</name>
<value>hdfs://master:9000</value>
</property>

<property>
<name>io.file.buffer.size</name>
<value>131072</value>
</property>

<property>
<name>hadoop.tmp.dir</name>
<value>/usr/bob/hadoop-2.7.1/tmp</value>
</property>

</configuration>

hdfs-site.xml

<?xml version="1.0" encoding="UTF-8"?>
<?xml-stylesheet type="text/xsl" href="configuration.xsl"?>
<!--
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License. See accompanying LICENSE file.
-->

<!-- Put site-specific property overrides in this file. -->

<configuration>
<property>
<name>dfs.namenode.name.dir</name>
<value>/home/bob/hadoop_space/hdfs/name</value>
</property> 

<property>
<name>dfs.datanode.data.dir</name>
<value>/home/bob/hadoop_space/hdfs/data</value>
</property>

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

<property>
<name>dfs.blocksize</name>
<value>268435456</value>
</property>

<property>
<name>dfs.namenode.handler.count</name>
<value>100</value>
</property>

<property>
<name>dfs.namenode.secondary.http-address</name>
<value>master:50090</value>
</property> 

<property>
<name>dfs.namenode.secondary.https-address</name>
<value>master:50091</value>
</property> 

</configuration>

mapred-site.xml

<?xml version="1.0"?>
<?xml-stylesheet type="text/xsl" href="configuration.xsl"?>
<!--
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License. See accompanying LICENSE file.
-->

<!-- Put site-specific property overrides in this file. -->

<configuration>

<property>
<name>mapreduce.framework.name</name>
<value>yarn</value>
</property>

<property>
<name>mapreduce.jobhistory.address</name>
<value>master:10020</value>
</property>

<property>
<name>mapreduce.jobhistory.webapp.address</name>
<value>master:19888</value>
</property>

</configuration>

yarn-site.xml

<?xml version="1.0"?>
<!--
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License. See accompanying LICENSE file.
-->
<configuration>

<!-- Site specific YARN configuration properties -->
<property>
<name>yarn.resourcemanager.hostname</name>
<value>10.204.16.59</value>
</property>

<property>
<name>yarn.nodemanager.aux-services</name>
<value>mapreduce_shuffle</value>
</property>

<property>
    <name>yarn.resourcemanager.address</name>
    <value>10.204.16.59:8032</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>

</configuration>

slaves(填写slave的主机名或ip，仅需要在master上设置)，内容如下：

　　slave7

　　slave8

三、初始化和启动

1、以bob用户登录格式化hdfs文件系统：hdfs namenode -format

运行格式化成功，节选输出最后三行如下：

　　15/08/25 18:09:54 INFO util.ExitUtil: Exiting with status 0
　　15/08/25 18:09:54 INFO namenode.NameNode: SHUTDOWN_MSG:
　　/************************************************************
　　SHUTDOWN_MSG: Shutting down NameNode at master/10.204.16.59
　　************************************************************/

2、启动hdfs：

以bob用户登录，启动hdfs集群：/usr/bob/hadoop-2.7.1/sbin/start-dfs.sh

输出如下：

15/08/25 19:00:28 WARN util.NativeCodeLoader: Unable to load native-hadoop library for your platform... using builtin-java classes where applicable
Starting namenodes on [master]
master: starting namenode, logging to /usr/bob/hadoop-2.7.1/logs/hadoop-bob-namenode-master.out
slave8: starting datanode, logging to /usr/bob/hadoop-2.7.1/logs/hadoop-bob-datanode-localhost.localdomain.out
slave7: starting datanode, logging to /usr/bob/hadoop-2.7.1/logs/hadoop-bob-datanode-slave7.out
Starting secondary namenodes [master]
master: starting secondarynamenode, logging to /usr/bob/hadoop-2.7.1/logs/hadoop-bob-secondarynamenode-master.out
15/08/25 19:00:49 WARN util.NativeCodeLoader: Unable to load native-hadoop library for your platform... using builtin-java classes where applicable

3、查看hdfs集群各主机的进程：jps

master上查看进程如下：
[bob@master sbin]$ jps
输出如下：

　　25551 Jps
　　25129 NameNode
　　25418 SecondaryNameNode

slave（slave7、slave8相同）上查看进程：

[bob@slave7 .ssh]$ jps
输出如下：

　　18468 DataNode
　　18560 Jps

4、启动yarn：

[bob@master sbin]$ ./start-yarn.sh
 输出如下：

　　starting yarn daemons
　　starting resourcemanager, logging to /usr/bob/hadoop-2.7.1/logs/yarn-bob-resourcemanager-master.out
　　slave8: starting nodemanager, logging to /usr/bob/hadoop-2.7.1/logs/yarn-bob-nodemanager-localhost.localdomain.out
　　slave7: starting nodemanager, logging to /usr/bob/hadoop-2.7.1/logs/yarn-bob-nodemanager-slave7.out

5、查看yarn启动后集群进程状态：

master上查看进程如下：

[bob@master sbin]$ jps
输出如下：

　　25129 NameNode
　　25633 ResourceManager
　　25418 SecondaryNameNode
　　25904 Jps

slave（slave7、slave8相同）上查看进程如下：

[bob@slave7 .ssh]$ jps
输出如下：

　　18468 DataNode
　　18619 NodeManager
　　18751 Jps

四、运行范例

1、创建hdfs文件

查看hdfs文件列表告警：

[bob@master sbin]$ hdfs dfs -ls /
15/08/25 19:23:13 WARN util.NativeCodeLoader: Unable to load native-hadoop library for your platform... using builtin-java classes where applicable

查看apache官网，NativeLibraryChecker is a tool to check whether native libraries are loaded correctly. You can launch NativeLibraryChecker as follows:

$ hadoop checknative -a
   14/12/06 01:30:45 WARN bzip2.Bzip2Factory: Failed to load/initialize native-bzip2 library system-native, will use pure-Java version
   14/12/06 01:30:45 INFO zlib.ZlibFactory: Successfully loaded & initialized native-zlib library
   Native library checking:
   hadoop: true /home/ozawa/hadoop/lib/native/libhadoop.so.1.0.0
   zlib:   true /lib/x86_64-linux-gnu/libz.so.1
   snappy: true /usr/lib/libsnappy.so.1
   lz4:    true revision:99
   bzip2:  false

但是我这里运行结果全是false：

[bob@master native]$ hadoop checknative -a
15/08/25 19:40:04 WARN util.NativeCodeLoader: Unable to load native-hadoop library for your platform... using builtin-java classes where applicable
Native library checking:
hadoop:  false
zlib:    false
snappy:  false
lz4:     false
bzip2:   false
openssl: false
15/08/25 19:40:04 INFO util.ExitUtil: Exiting with status 1

继续找原因，难道必需要重新编译hadoop源码？

---发现不影响正常功能，不知道如何消除此警告，先继续往下走吧。

2、上传本地文件至hdfs

-创建input、output文件夹用于后续输入、输出数据

[bob@master hadoop]$ hdfs dfs -mkdir /input

[bob@master hadoop]$ hdfs dfs -mkdir /output

-查看hdfs /目录下的文件信息

[bob@master hadoop]$ hdfs dfs –ls /

输出：

Found 5 items
drwxr-xr-x   - bob supergroup          0 2015-08-31 20:23 /input
drwxr-xr-x   - bob supergroup          0 2015-09-01 21:29 /output
drwxr-xr-x   - bob supergroup          0 2015-08-31 18:03 /test1
drwx------   - bob supergroup          0 2015-08-31 19:23 /tmp
drwxr-xr-x   - bob supergroup          0 2015-09-01 22:00 /user

-查看hdfs文件系统情况

[bob@master hadoop]$ hdfs dfsadmin -report

输出：
15/11/13 20:40:59 WARN util.NativeCodeLoader: Unable to load native-hadoop library for your platform... using builtin-java classes where applicable
Configured Capacity: 92229451776 (85.90 GB)
Present Capacity: 72146309120 (67.19 GB)
DFS Remaining: 71768203264 (66.84 GB)
DFS Used: 378105856 (360.59 MB)
DFS Used%: 0.52%
Under replicated blocks: 0
Blocks with corrupt replicas: 0
Missing blocks: 0
Missing blocks (with replication factor 1): 0

-------------------------------------------------
Live datanodes (2):

Name: 10.204.16.58:50010 (slave8)
Hostname: slave8
Decommission Status : Normal
Configured Capacity: 46114725888 (42.95 GB)
DFS Used: 378073088 (360.56 MB)
Non DFS Used: 10757623808 (10.02 GB)
DFS Remaining: 34979028992 (32.58 GB)
DFS Used%: 0.82%
DFS Remaining%: 75.85%
Configured Cache Capacity: 0 (0 B)
Cache Used: 0 (0 B)
Cache Remaining: 0 (0 B)
Cache Used%: 100.00%
Cache Remaining%: 0.00%
Xceivers: 1
Last contact: Fri Nov 13 20:41:00 CST 2015

Name: 10.204.16.57:50010 (slave7)
Hostname: slave7
Decommission Status : Normal
Configured Capacity: 46114725888 (42.95 GB)
DFS Used: 32768 (32 KB)
Non DFS Used: 9325518848 (8.69 GB)
DFS Remaining: 36789174272 (34.26 GB)
DFS Used%: 0.00%
DFS Remaining%: 79.78%
Configured Cache Capacity: 0 (0 B)
Cache Used: 0 (0 B)
Cache Remaining: 0 (0 B)
Cache Used%: 100.00%
Cache Remaining%: 0.00%
Xceivers: 1
Last contact: Fri Nov 13 20:41:01 CST 2015

-创建wordcount文件夹hdfs dfs -mkdir /input/wordcount

-将本地/home/bob/study/下的所有txt文件上传到hdfs的/input/wordcount文件夹下

[bob@master hadoop]$ hdfs dfs -put /home/bob/study/*.txt  /input/wordcount

-查看上传后的文件清单：

[bob@master hadoop]$ hadoop dfs -ls /input/wordcount
-rw-r--r--   3 bob supergroup        100 2015-11-13 21:02 /input/wordcount/file1.txt
-rw-r--r--   3 bob supergroup        383 2015-11-13 21:03 /input/wordcount/file2.txt
-rw-r--r--   2 bob supergroup         73 2015-08-31 19:18 /input/wordcount/runHadoop.txt

3、运行自带的wordcount范例。

[bob@master hadoop]$ hadoop jar /usr/bob/hadoop-2.7.1/share/hadoop/mapreduce/hoop-mapreduce-examples-2.7.1.jar wordcount /input/wordcount/*.txt /output/wordcount
15/11/13 21:41:14 WARN util.NativeCodeLoader: Unable to load native-hadoop library for your platform... using builtin-java classes where applicable
15/11/13 21:41:16 INFO client.RMProxy: Connecting to ResourceManager at /10.204.16.59:8032
15/11/13 21:41:17 INFO input.FileInputFormat: Total input paths to process : 3
15/11/13 21:41:17 INFO mapreduce.JobSubmitter: number of splits:3
15/11/13 21:41:18 INFO mapreduce.JobSubmitter: Submitting tokens for job: job_1441114883272_0008
15/11/13 21:41:18 INFO impl.YarnClientImpl: Submitted application application_1441114883272_0008
15/11/13 21:41:18 INFO mapreduce.Job: The url to track the job: http://master:8088/proxy/application_1441114883272_0008/
15/11/13 21:41:18 INFO mapreduce.Job: Running job: job_1441114883272_0008
15/11/13 21:50:57 INFO mapreduce.Job: Job job_1441114883272_0008 running in uber mode : false
15/11/13 21:50:57 INFO mapreduce.Job:  map 0% reduce 0%
15/11/13 21:51:10 INFO mapreduce.Job:  map 100% reduce 0%
15/11/13 21:58:31 INFO mapreduce.Job: Task Id : attempt_1441114883272_0008_r_000000_0, Status : FAILED
Container launch failed for container_1441114883272_0008_01_000005 : java.net.NoRouteToHostException: No Route to Host from  slave8/10.204.16.58 to slave7:45758 failed on socket timeout exception: java.net.NoRouteToHostException: No route to host; For more details see:  http://wiki.apache.org/hadoop/NoRouteToHost
        at sun.reflect.GeneratedConstructorAccessor22.newInstance(Unknown Source)
        at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
        at java.lang.reflect.Constructor.newInstance(Constructor.java:526)
        at org.apache.hadoop.net.NetUtils.wrapWithMessage(NetUtils.java:792)
        at org.apache.hadoop.net.NetUtils.wrapException(NetUtils.java:758)
        at org.apache.hadoop.ipc.Client.call(Client.java:1480)
        at org.apache.hadoop.ipc.Client.call(Client.java:1407)
        at org.apache.hadoop.ipc.ProtobufRpcEngine$Invoker.invoke(ProtobufRpcEngine.java:229)
        at com.sun.proxy.$Proxy36.startContainers(Unknown Source)
        at org.apache.hadoop.yarn.api.impl.pb.client.ContainerManagementProtocolPBClientImpl.startContainers(ContainerManagementProtocolPBClientImpl.java:96)
        at sun.reflect.GeneratedMethodAccessor3.invoke(Unknown Source)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
        at java.lang.reflect.Method.invoke(Method.java:606)
        at org.apache.hadoop.io.retry.RetryInvocationHandler.invokeMethod(RetryInvocationHandler.java:187)
        at org.apache.hadoop.io.retry.RetryInvocationHandler.invoke(RetryInvocationHandler.java:102)
        at com.sun.proxy.$Proxy37.startContainers(Unknown Source)
        at org.apache.hadoop.mapreduce.v2.app.launcher.ContainerLauncherImpl$Container.launch(ContainerLauncherImpl.java:151)
        at org.apache.hadoop.mapreduce.v2.app.launcher.ContainerLauncherImpl$EventProcessor.run(ContainerLauncherImpl.java:375)
        at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
        at java.lang.Thread.run(Thread.java:745)
Caused by: java.net.NoRouteToHostException: No route to host
        at sun.nio.ch.SocketChannelImpl.checkConnect(Native Method)
        at sun.nio.ch.SocketChannelImpl.finishConnect(SocketChannelImpl.java:739)
        at org.apache.hadoop.net.SocketIOWithTimeout.connect(SocketIOWithTimeout.java:206)
        at org.apache.hadoop.net.NetUtils.connect(NetUtils.java:531)
        at org.apache.hadoop.net.NetUtils.connect(NetUtils.java:495)
        at org.apache.hadoop.ipc.Client$Connection.setupConnection(Client.java:609)
        at org.apache.hadoop.ipc.Client$Connection.setupIOstreams(Client.java:707)
        at org.apache.hadoop.ipc.Client$Connection.access$2800(Client.java:370)
        at org.apache.hadoop.ipc.Client.getConnection(Client.java:1529)
        at org.apache.hadoop.ipc.Client.call(Client.java:1446)
        ... 15 more

15/11/13 21:58:40 INFO mapreduce.Job:  map 100% reduce 100%
15/11/13 21:58:41 INFO mapreduce.Job: Job job_1441114883272_0008 completed successfully
15/11/13 21:58:41 INFO mapreduce.Job: Counters: 49
        File System Counters
                FILE: Number of bytes read=680
                FILE: Number of bytes written=462325
                FILE: Number of read operations=0
                FILE: Number of large read operations=0
                FILE: Number of write operations=0
                HDFS: Number of bytes read=887
                HDFS: Number of bytes written=327
                HDFS: Number of read operations=12
                HDFS: Number of large read operations=0
                HDFS: Number of write operations=2
        Job Counters
                Launched map tasks=3
                Launched reduce tasks=1
                Data-local map tasks=3
                Total time spent by all maps in occupied slots (ms)=30688
                Total time spent by all reduces in occupied slots (ms)=6346
                Total time spent by all map tasks (ms)=30688
                Total time spent by all reduce tasks (ms)=6346
                Total vcore-seconds taken by all map tasks=30688
                Total vcore-seconds taken by all reduce tasks=6346
                Total megabyte-seconds taken by all map tasks=31424512
                Total megabyte-seconds taken by all reduce tasks=6498304
        Map-Reduce Framework
                Map input records=13
                Map output records=52
                Map output bytes=752
                Map output materialized bytes=692
                Input split bytes=331
                Combine input records=52
                Combine output records=45
                Reduce input groups=25
                Reduce shuffle bytes=692
                Reduce input records=45
                Reduce output records=25
                Spilled Records=90
                Shuffled Maps =3
                Failed Shuffles=0
                Merged Map outputs=3
                GC time elapsed (ms)=524
                CPU time spent (ms)=5900
                Physical memory (bytes) snapshot=1006231552
                Virtual memory (bytes) snapshot=4822319104
                Total committed heap usage (bytes)=718798848
        Shuffle Errors
                BAD_ID=0
                CONNECTION=0
                IO_ERROR=0
                WRONG_LENGTH=0
                WRONG_MAP=0
                WRONG_REDUCE=0
        File Input Format Counters
                Bytes Read=556
        File Output Format Counters
                Bytes Written=327
运行过程中抛出异常，如下：

5/11/13 21:58:31 INFO mapreduce.Job: Task Id : attempt_1441114883272_0008_r_000000_0, Status : FAILED
Container
launch failed for container_1441114883272_0008_01_000005 :
java.net.NoRouteToHostException: No Route to Host from 
slave8/10.204.16.58 to slave7:45758 failed on socket timeout exception:
java.net.NoRouteToHostException: No route to host; For more details
see:  http://wiki.apache.org/hadoop/NoRouteToHost

在等待较长时间后，最终运行成功，报错的原因以后继续分析。

-运行成功后，在 /output/wordcount下自动生成两个文件：_SUCCESS、part-r-00000，可用hdfs命令查看：

[bob@master hadoop]$ hdfs dfs -ls /output/wordcount
15/11/13 22:31:59 WARN util.NativeCodeLoader: Unable to load native-hadoop library for your platform... using builtin-java classes where applicable
Found 2 items
-rw-r--r--   2 bob supergroup          0 2015-11-13 21:58 /output/wordcount/_SUCCESS
-rw-r--r--   2 bob supergroup        327 2015-11-13 21:58 /output/wordcount/part-r-00000

-显示part-r-00000文件内容，命令及输出如下：

[bob@master hadoop]$ hdfs dfs -cat /output/wordcount/part-r-00000
15/11/13 22:34:07 WARN util.NativeCodeLoader: Unable to load native-hadoop library for your platform... using builtin-java classes where applicable
/home/bob/study/hello.jar       1
/input/*.txt    2
/input/wordcount        1
/output/wordcount       3
/usr/bob/hadoop-2.7.1/share/hadoop/mapreduce/hadoop-mapreduce-examples-2.7.1.jar2
day     2
example 2
first   2
hadoop  5
hello   2
i       2
in      2
is      2
it      2
jar     3
my      2
myself,come     2
nice    2
on.     2
succeed 2
wordcount       2
中国人  1
中国梦  2
学习    2
学校    2
-------------------------------------------------------------------------

ok，第一次完整搭建过程说完了，欢迎批评指正。

posted @ 2015-08-25 14:26 Bob.Guo

first updated @ 2015-11-13 20:29 Bob.Guo