Hadoop用户配置ssh免密登录

一般生产环境 Hadoop组件都是由hadoop用户来启动，首先需要配置hadoop用户ssh免密登录

1.创建Hadoop用户

[root@hadoop000 ~]# useradd hadoop[root@hadoop000 ~]# id hadoopuid=1102(hadoop) gid=1102(hadoop) groups=1102(hadoop)[root@hadoop000 ~]# passwd hadoopChanging password for user hadoop.New password: BAD PASSWORD: it is too simplistic/systematicBAD PASSWORD: is too simpleRetype new password: passwd: all authentication tokens updated successfully.#给hadoop sudo权限[root@hadoop000 ~]# vi /etc/sudoershadoop ALL=(root) NOPASSWD:ALL

2.切换到hadoop用户 配置免密登录

[root@hadoop000 ~]# su - hadoop#确保有ssh服务[hadoop@hadoop000 ~]$ sudo service sshd statusopenssh-daemon (pid  24823) is running...[hadoop@hadoop000 ~]$ ssh-keygenGenerating public/private rsa key pair.Enter file in which to save the key (/home/hadoop/.ssh/id_rsa): Created directory '/home/hadoop/.ssh'.Enter passphrase (empty for no passphrase): Enter same passphrase again: Your identification has been saved in /home/hadoop/.ssh/id_rsa.Your public key has been saved in /home/hadoop/.ssh/id_rsa.pub.The key fingerprint is:bd:75:87:ca:44:2d:1f:de:b7:5e:a0:96:ac:b3:7e:01 hadoop@hadoop000The key's randomart image is:+--[ RSA 2048]----+|                 ||             .   ||            o o  ||         .E. + + ||        S ..o * +||           *.= oo||          . B. ..||          .o. . .||         .++   . |+-----------------+[hadoop@hadoop000 ~]$ cd .ssh[hadoop@hadoop000 .ssh]$ lltotal 8-rw------- 1 hadoop hadoop 1675 May 17 14:59 id_rsa-rw-r--r-- 1 hadoop hadoop  395 May 17 14:59 id_rsa.pub[hadoop@hadoop000 .ssh]$ cat id_rsa.pub >> authorized_keys[hadoop@hadoop000 .ssh]$ lltotal 12-rw-rw-r-- 1 hadoop hadoop  395 May 17 14:59 authorized_keys-rw------- 1 hadoop hadoop 1675 May 17 14:59 id_rsa-rw-r--r-- 1 hadoop hadoop  395 May 17 14:59 id_rsa.pub#authorized_keys权限必须为600[hadoop@hadoop000 .ssh]$ chmod 600 authorized_keys[hadoop@hadoop000 .ssh]$ ssh hadoop000 dateThe authenticity of host 'hadoop000 (192.168.6.217)' can't be established.RSA key fingerprint is 25:d9:d6:7e:fa:e0:a7:92:7c:06:76:5c:2b:19:bf:a3.Are you sure you want to continue connecting (yes/no)? yesWarning: Permanently added 'hadoop000,192.168.6.217' (RSA) to the list of known hosts.Thu May 17 15:00:28 CST 2018[hadoop@hadoop000 .ssh]$ ssh hadoop000 dateThu May 17 15:00:30 CST 2018

3.总结

hadoop用户配置ssh免密登录 authorized_keys权限必须改为600