1.下载并安装安装sshsudo apt-get install openssh-server openssh-client3.搭建vsftpd#sudo apt-get update#sudo apt-get install vsftpd配置参考的开始、关闭和重启$sudo /etc/vsftpd start #开始$sudo /etc/vsftpd stop #关闭$sudo /etc/vsftpd restart #重启4.安装sudo chown -R hadoop:hadoop /optcp /soft/ /optsudo vi /etc/profilealias untar='tar -zxvf'sudo source /etc/profilesource /etc/profileuntar jdk*环境变量配置# vi /etc/profile●在profile文件最后加上# set java environmentexport JAVA_HOME=/opt/export CLASSPATH=.:$JAVA_HOME/lib/:$JAVA_HOME/lib/ export PATH=$JAVA_HOME/bin:$PATH配置完成后，保存退出。
●不重启，更新命令#source /etc/profile●测试是否安装成功# Java –version其他问题：出现unable to resolve host 解决方法参考开机时停在Starting sendmail 不动了的解决方案参考安装软件时出现E: Unable to locate package vsftpd 参考vi/vim 使用方法讲解参考分类: Hadoop--------------------------------------------克隆master虚拟机至node1 、node2分别修改master的主机名为master、node1的主机名为node1、node2的主机名为node2 (启动node1、node2系统默认分配递增ip，无需手动修改)分别修改/etc/hosts中的ip和主机名(包含其他节点ip和主机名)---------配置ssh免密码连入hadoop@node1:~$ ssh-keygen -t dsa -P ''-f ~/.ssh/id_dsaGenerating public/private dsa key pair.Created directory '/home/hadoop/.ssh'.Your identification has been saved in/home/hadoop/.ssh/id_dsa.Your public key has been saved in/home/hadoop/.ssh/.The key fingerprint is:SHA256:B8vBju/uc3kl/v9lrMqtltttttCcXgRkQPbVoU hadoop@node1The key's randomart image is:+---[DSA 1024]----+|....||o+.E .||. oo +||..++||o +.o ooo +||=o.. o. ooo. o.||*o....+=o .+++.+|+----[SHA256]-----+hadoop@node1:~$ cd .sshhadoop@node1:~/.ssh$ ll总用量16drwx------ 2 hadoop hadoop 4096 Jul 24 20:31 ./drwxr-xr-x 18 hadoop hadoop 4096 Jul 2420:31../-rw------- 1 hadoop hadoop 668 Jul 24 20:31 id_dsa-rw-r--r-- 1 hadoop hadoop 602 Jul 24 20:31hadoop@node1:~/.ssh$ cat >> authorized_keyshadoop@node1:~/.ssh$ ll总用量20drwx------ 2 hadoop hadoop 4096 Jul 24 20:32 ./drwxr-xr-x 18 hadoop hadoop 4096 Jul 2420:31../-rw-rw-r-- 1 hadoop hadoop 602 Jul 24 20:32 authorized_keys-rw------- 1 hadoop hadoop 668 Jul 24 20:31 id_dsa-rw-r--r-- 1 hadoop hadoop 602 Jul 24 20:31单机回环ssh免密码登录测试hadoop@node1:~/.ssh$ ssh localhostThe authenticity of host'localhost ' can't be established.ECDSA key fingerprint is SHA256:daO0dssyqt12tt9yGUauImOh6tt6A1SgxzSfSmpQqJVEiQTxas. Are you sure you want to continue connecting (yes/no) yesWarning: Permanently added 'localhost'(ECDSA)to the list of known hosts.Welcome to Ubuntu (GNU/Linux x86_64)* Documentation:packages can be updated.178 updates are security updates.New release' LTS' available.Run 'do-release-upgrade'to upgrade to it.Last login: Sun Jul 2420:21:392016from exit注销Connection to localhost closed.hadoop@node1:~/.ssh$出现以上信息说明操作成功,其他两个节点同样操作让主结点(master)能通过SSH免密码登录两个子结点（slave）hadoop@node1:~/.ssh$ scp hadoop@master:~/.ssh/./The authenticity of host'master ' can't be established.ECDSA key fingerprint is SHA256:daO0dssyqtt9yGUuImOh646A1SgxzSfatSmpQqJVEiQTxas.Are you sure you want to continue connecting (yes/no) yesWarning: Permanently added 'master,'(ECDSA)to the list of known hosts.hadoop@master's password:100%603s 00:00 hadoop@node1:~/.ssh$ cat >> authorized_keys如上过程显示了node1结点通过scp命令远程登录master结点，并复制master的公钥文件到当前的目录下，这一过程需要密码验证。
接着，将master结点的公钥文件追加至authorized_keys文件中，通过这步操作，如果不出问题，master结点就可以通过ssh远程免密码连接node1结点了。
在master结点中操作如下：hadoop@master:~/.ssh$ ssh node1The authenticity of host'node1 ' can't be established.ECDSA key fingerprint is SHA256:daO0dssyqt9yGUuImOh3466A1SttgxzSfSmpQqJVEiQTxas.Are you sure you want to continue connecting (yes/no) yesWarning: Permanently added 'node1,'(ECDSA)to the list of known hosts.Welcome to Ubuntu (GNU/Linux x86_64)* Documentation:packages can be updated.178 updates are security updates.New release' LTS' available.Run 'do-release-upgrade'to upgrade to it.Last login: Sun Jul 2420:39:302016from exit注销Connection to node1 closed.hadoop@master:~/.ssh$由上图可以看出，node1结点首次连接时需要，“YES”确认连接，这意味着master结点连接node1结点时需要人工询问，无法自动连接，输入yes后成功接入，紧接着注销退出至master结点。
要实现ssh免密码连接至其它结点，还差一步，只需要再执行一遍ssh node1，如果没有要求你输入”yes”，就算成功了，过程如下：hadoop@master:~/.ssh$ ssh node1Welcome to Ubuntu (GNU/Linux x86_64)* Documentation:packages can be updated.178 updates are security updates.New release' LTS' available.Run 'do-release-upgrade'to upgrade to it.Last login: Sun Jul 2420:47:202016from exit注销Connection to node1 closed.hadoop@master:~/.ssh$如上图所示，master已经可以通过ssh免密码登录至node1结点了。
对node2结点也可以用上面同样的方法进行表面上看，这两个结点的ssh免密码登录已经配置成功，但是我们还需要对主结点master也要进行上面的同样工作，这一步有点让人困惑，但是这是有原因的，具体原因现在也说不太好，据说是真实物理结点时需要做这项工作，因为jobtracker有可能会分布在其它结点上，jobtracker有不存在master结点上的可能性。