??????.???Hadoop
????1.???Hadoop?????usr/hadoop1.2.1file?￡??????????????????
????<span style="font-family: ????; font-size: 18pt;">sudo  tar  -zxvf  hadoop-1.2.1.tar.gz
????//hxsyl????????????
????sudo  chown  -hR  hxsyl  /usr/hadoop1.2.1file
????</span>
????2.???????????
??????????????????????jdk???????????????????????????????ok??
????3.???e?????Э??
??????????OpenSSH??Hadoop??????SSH?????Slave?б??и???????????????????SSH????譎???????????????????????α??????????????Hadoop??????????????α??????????α??????Hadoop??????????????????????????????????conf/slaves?м????????????????????α??????Salve?localhost????????????α??????SSH???????
????<span style="font-family: ????; font-size: 18pt;">//???ù????????????????????磩??
????//???SSH??????????????????
????sudo  apt-get install openssh-server
????//???????????????????
????//??????????????????е?ssh??滹?????“.”????????
????ssh-keygen  -t  dsa -P '' -f  ~/.ssh/id_dsa
?????????????????????????ssh-keygen ?????????????-t ???????????????????dsa ??dsa?????????????-P ???????????????????????????????????????-f ??????????????????
????????????????????????????????.ssh??????′???id_dsa??id_dsa.pub?????????????SSH???????????????id_dsa.pub????????????????key?????????????????
????cat  ~/.ssh/id_dsa.pub  >>  ~/.ssh/authorized_keys
????????????????????SSH??????????????′???.ssh???????????У??????????????????????????????????????????ls???????
????????ssh  localhost????????????????
????</span>
??????.????hadoopα????
????1.??????????Hadoop??????У?????????conf????У???????;????hadoop???????hadoop-env.sh;???????????????”# export JAVA_HOME = ...” ?????????????“#”??????????????д???????JDK·????
????2.????Hadoop????????core-site.xml???????????????<configuration></configuration>????????????????????????
????<span style="font-family: ????; font-size: 18pt;"><property>
????<name>fs.default.name</name>
????<value>hdfs://localhost:9000</value>
????</property>
????<property>
????<name>dfs.replication</name>
????<value>1</value>
????</property>
????<property>
????<name>hadoop.tmp.dir</name>
????<value>/home/hxsyl/tmp</value>
????</property>
????</span>
?????????????value??У???????hxsyl?????????????????????????????????????????????????????
????3.????Hadoop??MapReduce?????????mapred-site.xml???????????????<configuration></configuration>????????????????????????
????<span style="font-family: ????; font-size: 18pt;"><property>
????<name>mapred.job.tracker</name>
????<value>localhost:9001</value>
????</property>
????</span>
????4.????Hadoop??hdfs-site.xml????????????????????<configuration></configuration>?м?????′???
????<span style="font-family: ????; font-size: 18pt;"><property>
????<name>dfs.name.dir</name>
????<value>/usr/hadoop1.2.1file/hadoop-1.2.1/datalog1??/usr/local/hadoop/hadoop-1.2.1/datalog2</value>
????</property>
????<property>
????<name>dfs.data.dir</name>
????<value>/usr/hadoop1.2.1file/hadoop-1.2.1/data1??/usr/local/hadoop/hadoop-1.2.1/data2</value>
????</property>
????<property>
????<name>dfs.replication</name>
????<value>2</value>
????</property>
????</span>
?????????????????????????棬???
????<span style="font-family: ????; font-size: 18pt;">sudo gedit ...................
????</span>
??????.?????HDFS?????Hadoop
????1.???????hadoop??????и????Hadoop?????????????м????????????????У????????Hadoop?????·???￡????????????????
????<span style="font-family: ????; font-size: 18pt;">bin/hadoop  namenode -format
????//??????????????????Hadoop??????????????????
????bin/start-all.sh
????</span>
????2.???????????????????????????????jps?????????
????jps(Java Virtual Machine Process Status Tool)??JDK 1.5?????????????????java????pid????????????????????linux/unix??????????java??????Щ???????
???????hadoop
????<span style="font-family: ????; font-size: 18pt;">bin/stop-all.sh   </span>
????3.???????WordCount??????????????????????