hadoop安裝配置：使用cloudrea

這裏使用cloudrea的rpm源，安裝hadoop

環境爲：

192.168.255.132 test01.linuxjcq.com =》master
192.168.255.133 test02.linuxjcq.com =》slave01
192.168.255.134 test03.linuxjcq.com =》slave02

每臺主機中的/etc/hosts文件有以上配置和基本的java環境設置，使用的java包爲openjdk

1. 安裝cloudrea

wget http://archive.cloudera.com/redhat/6/x86_64/cdh/cdh3-repository-1.0-1.noarch.rpm -P /usr/local/src

yum localinstall --nogpgcheck /usr/local/src/cdh3-repository-1.0-1.noarch.rpm

rpm --import http://archive.cloudera.com/redhat/6/x86_64/cdh/RPM-GPG-KEY-cloudera 

2. 安裝hadoop包

yum install hadoop-0.20 hadoop-0.20-namenode hadoop-0.20-secondarynamenode hadoop-0.20-datanode hadoop-0.20-jobtracker hadoop-0.20-tasktracker hadoop-0.20-source

將hadoop按照各個部分的功能分爲了

source：hadoop-0.20-source

base：hadoop-0.20

namenode：hadoop-0.20-namenode

secondnamenode：hadoop-0.20-secondarynamenode

jobtracker：hadoop-0.20-jobtracker

tasktracker：hadoop-0.20-tasktracker

同時會默認添加兩個用戶和一個組

hdfs用戶用於操作hdfs文件系統

mapred用戶用於mapreduce工作

這兩個用戶都屬於hadoop組，不存在hadoop用戶。

以上1,2在每一個節點都需進行操作

3. 配置master節點

a. 創建配置

cloudrea配置可以通過alternatives工具

cp -r /etc/hadoop-0.20/conf.empty /etc/hadoop-0.20/conf.my_cluster

複製配置文件

alternatives --display hadoop-0.20-conf

alternatives --install /etc/hadoop-0.20/conf
hadoop-0.20-conf /etc/hadoop-0.20/conf.my_cluster 50

查看配置，並安裝新的配置

alternatives --display hadoop-0.20-conf
hadoop-0.20-conf - status is auto.
 link currently points to /etc/hadoop-0.20/conf.my_cluster
/etc/hadoop-0.20/conf.empty - priority 10
/etc/hadoop-0.20/conf.my_cluster - priority 50
Current `best' version is /etc/hadoop-0.20/conf.my_cluster.

確認安裝了新配置

b. 設置java主目錄

vi hadoop-env.sh
export JAVA_HOME=/usr/lib/jvm/java-1.6.0-openjdk-1.6.0.0.x86_64

JAVA_HOME爲JAVA的主目錄，可以使用OPENJDK

c. 設置core-site.xml

vi core-site.xml
<configuration>
  <property>
    <name>fs.default.name</name>
    <value>hdfs://test01.linuxjcq.com:9000/</value>
  </property>
</configuration>

使用這個訪問hdfs文件系統

d. 設置hdfs-site.xml

vi /etc/hadoop/hdfs-site.xml
<configuration>
  <property>
    <name>dfs.replication</name>
    <value>2</value>
  </property>
  <property>
    <name>dfs.name.dir</name>
    <value>/data/hadoop/hdfs/name</value>
  </property>
  <property>
    <name>dfs.data.dir</name>
    <value>/data/hadoop/hdfs/data</value>
  </property>
</configuration>

e. 設置mapred-site.xml

<configuration>
  <property>
    <name>mapred.system.dir</name>
    <value>/mapred/system</value>
  </property>
  <property>
    <name>mapred.local.dir</name>
    <value>/data/hadoop/mapred/local</value>
  </property>
  <property>
    <name>mapred.job.tracker</name>
    <value>test01.linuxjcq.com:9001</value>
  </property>
</configuration>

f. 設置secondnamenode和datanode

secondnamenode

vi /etc/hadoop/masters
test02.linuxjcq.com

datanode

test02.linuxjcq.com
test03.linuxjcq.com

g. 創建相應的目錄

創建dfs.name.dir和dfs.data.dir

mkdir -p /data/hadoop/hdfs/{name,data}

創建mapred.local.dir

mkdir -p /data/hadoop/mapred/local

修改dfs.name.dir和dfs.data.dir擁有者爲hdfs，組擁有者爲hadoop，目錄權限爲0700

chown -R hdfs:hadoop /data/hadoop/hdfs/{name,data}

chmod -R 0700 /data/hadoop/hdfs/{name,data}

修改mapred.local.dir擁有者爲mapred，組擁有者爲hadoop，目錄權限爲755

chown -R mapred:hadoop /data/hadoop/mapred/local

chmod -R 0755 /data/hadoop/mapred/local

4. 配置secondnamenode和datanode節點

重複3中的步驟a-f

5. 在master節點上格式化namenode

sudo -u hdfs hadoop namenode -format

6. 啓動節點

master啓動namenode

service hadoop-0.20-namenode start

secondnamenode啓動

service hadoop-0.20-secondnamenode start

啓動各個數據節點

service hadoop-0.20-datanode start

7. 創建hdfs的/tmp目錄和mapred.system.dir

sudo -u hdfs hadoop fs -mkdir /mapred/system
sudo -u hdfs hadoop fs -chown mapred:hadoop /mapred/system
sudo -u hdfs hadoop fs -chmod 700 /mapred/system

mapred.system.dir需要在jobtracker啓動前創建

sudo -u hdfs hadoop dfs -mkdir /tmp
sudo -u hdfs hadoop dfs -chmod -R 1777 /tmp

8. 開啓mapreduce

在datanode節點上執行

service hadoop-0.20-tasktracker start

在namenode節點上啓動jobtracker

service hadoop-0.20-jobtasker start

9. 設置開機啓動

namenode節點：需要啓動的爲namenode何jobtracker，關閉其他的服務

chkconfig hadoop-0.20-namenode on
chkconfig hadoop-0.20-jobtracker on
chkconfig hadoop-0.20-secondarynamenode off
chkconfig hadoop-0.20-tasktracker off
chkconfig hadoop-0.20-datanode off

datanode節點：需要啓動datanode和tasktracker

chkconfig hadoop-0.20-namenode off
chkconfig hadoop-0.20-jobtracker off
chkconfig hadoop-0.20-secondarynamenode off
chkconfig hadoop-0.20-tasktracker on
chkconfig hadoop-0.20-datanode on

secondarynamenode節點：需要啓動secondarynamenode

chkconfig hadoop-0.20-secondarynamenode on

說明：

這些hadoop包作爲獨立的服務啓動，不需要通過ssh，也可以配置ssh，通過使用start-all.sh和stop-all.sh來管理服務。