Hadoop users configure ssh secret-free login
In general, the Hadoop components of the production environment are started by the hadoop user. First, you need to configure the hadoop user ssh secret-free login.
1. Create Hadoop user [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.# give hadoop sudo permission [root@hadoop000 ~] # vi / etc/sudoershadoop ALL= (root) NOPASSWD:ALL2. Switch to hadoop user configuration secret-free login [root@hadoop000 ~] # su-hadoop# ensure that there is a ssh service [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]-+ | |. | | oo | | .e. + + | | S.. o * + | | *. = oo | |. B. | | .o. . . | |. +. | | +-+ [hadoop@hadoop000 ~] $cd .ssh [hadoop@hadoop000 .ssh] $lltotal 8hadoop000 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 RWL RWL-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 permission must be 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 'hadoop000192.168.6.217' (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 20183. Summary
Hadoop users configure ssh secret-free login authorized_keys permissions must be changed to 600,
