配置环境
准备： 三台虚拟机
配置主节点：
1. 查看当前使用网卡
[root@localhost ~]# dmesg | grep -i ethBluetooth: BNEP (Ethernet Emulation) ver 1.3eth0: no IPv6 routers presentdmesg是显示开机启动信息， grep -i是忽略大小写查找
2. 查看当前ip、网关
[root@localhost ~]# ifconfigeth0 Link encap:Ethernet HWaddr 00:0C:29:E0:C3:61 inet addr:192.168.182.138 Bcast:192.168.182.255 Mask:255.255.255.0 inet6 addr: fe80::20c:29ff:fee0:c361/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:24092 errors:0 dropped:0 overruns:0 frame:0 TX packets:12373 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:35176927 (33.5 MiB) TX bytes:672502 (656.7 KiB) Interrupt:19 Base address:0x2024 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:8 errors:0 dropped:0 overruns:0 frame:0 TX packets:8 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:0 RX bytes:480 (480.0 b) TX bytes:480 (480.0 b)配置静态IP：
[root@localhost ~]# vi /etc/sysconfig/network-scripts/ifcfg-eth0DEVICE="eth0"#BOOTPROTO="dhcp"BOOTPROTO="static"HWADDR="00:0C:29:E0:C3:61"#IPV6INIT="yes"IPV6INIT="no"NM_CONTROLLED="yes"ONBOOT="yes"TYPE="Ethernet"UUID="7039ffae-3334-4445-b571-a805eecd4a77"IPADDR=192.168.182.101NETMASK=255.255.255.0GATEWAY=192.168.182.255修改主机名：
[root@localhost ~]# vi /etc/sysconfig/networkNETWORKING=yesHOSTNAME=master[root@localhost ~]# hostname master[root@localhost ~]# hostnamemaster
修改hosts文件：
[root@localhost ~]# vi /etc/hosts127.0.0.1 localhost localhost.localdomain localhost4 localhost4.localdomain4::1 localhost localhost.localdomain localhost6 localhost6.localdomain6192.168.182.100 master192.168.182.101 slave1192.168.182.102 slave2关闭防火墙（生产环境不能关闭， 需要添加允许列表）
[root@localhost ~]# service iptables stopiptables: Setting chains to policy ACCEPT: filter [ OK ]iptables: Flushing firewall rules: [ OK ]iptables: Unloading modules: [ OK ][root@localhost ~]# chkconfig iptables off关闭 selinux
[root@localhost ~]# vi /etc/selinux/config
将SELINUX的值对应修改为： SELINUX=disabled
将两台从属节点按照上面的配置配好， ip分别设置为192.168.182.102和192.168.182.103， 主机名分别为slave1、slave2。
创建相同的用户（三台主机）
#useradd hadoop#passwd hadoop
配置无密码访问
三台机器上分别执行以下语句：
[hadoop@master .ssh]$ ssh-keygen -t rsa[hadoop@master .ssh]$ cat ~/.ssh/id_rsa.pub >> ~/.ssh/authorized_keys
将salve1和slave2上生成的authorized_keys文件拷贝到master上
scp ~/.ssh/authorized_keys master:~/.ssh/authorized_keys1scp ~/.ssh/authorized_keys master:~/.ssh/authorized_keys2合并文件
cat authorized_keys1 >> authorized_keyscat authorized_keys2 >> authorized_keys
将master主机上合并后的authorized_keys文件复制到salve1和slaver2上
scp ~/.ssh/authorized_keys slave1:~/.ssh/scp ~/.ssh/authorized_keys slave2:~/.ssh/
三台主机上执行:
$ chmod 600 authorized_keys
验证 $ ssh slave1
$ ssh slave2
配置hadoop
上传hadoop-1.2.1.tar.gz到home目录， 解压后确认所属用户和组都是hadoop
$ tar xzvf hadoop-1.2.1-bin.tar.gz$ chown -R hadoop:hadoop hadoop-1.2.1
配置hadoop用户的.bashrc文件：
export JAVA_HOME=/usr/java/jdk1.6.0_45export PATH=$PATH:$JAVA_HOME/binexport CLASSPATH=$CLASSPATH:$JAVA_HOME/lib
发送到另外两台主机
$ scp .bashrc slave1:~ $ scp .bashrc slave2:~
修改hadoop-env.sh文件
[hadoop@master ~]$ vi hadoop-1.2.1/conf/hadoop-env.sh
修改：
export JAVA_HOME=/usr/java/jdk1.6.0_45 export HADOOP_HEAPSIZE=20修改core-site.xml
[hadoop@master ~]$ vi hadoop-1.2.1/conf/core-site.xml文件内容:
hadoop会自动创建/home/hadoop/tmp 修改 hdfs-site.xmlhadoop.tmp.dir /home/hadoop/tmp fs.default.name hdfs://master:9000
[hadoop@master ~]$ vi hadoop-1.2.1/conf/hdfs-site.xml文件内容：
修改mapred-site.xml， 文件内容：dfs.data.dir /home/hadoop/data dfs.replication 2
修改master文件：mapred.job.tracker master:9001
master修改slave文件：
slave1slave2
将master节点上配置好的hadoop发送到slave1、slave2节点
$ scp -r ./hadoop-1.2.1 slave1:/home/hadoop$ scp -r ./hadoop-1.2.1 slave2:/home/hadoop
格式化HDFS $ ./hadoop namenode -format
运行start-all.sh（只在主节点运行）
$ ./start-all.sh
通过jps命令检测启动情况
master节点上应该存在：NameNode、SecondaryNameNode、JobTracker
slave1、slave2节点上存在：DataNode、TaskTracker
查看运行情况
1）
[hadoop@master bin]$ hadoop dfsadmin -report2）
http://192.168.182.100:50070/dfshealth.jsp
http://192.168.182.100:50030/jobtracker.jsp