id_rsa叫私钥，也就是钥匙，id_rsa.pub叫公钥。
ssh-keygen <== 建立密钥对
Your identification has been saved in /root/.ssh/id_rsa. <== 私钥
Your public key has been saved in /root/.ssh/id_rsa.pub. <== 公钥
===============================================================================
一、服务机1：Hadoop1实验
1、创建Hadoop1账户，并设置密码
[root@localhost ~]# useradd hadoop1
[root@localhost ~]# passwd hadoop1
更改用户 hadoop1 的密码 。
新的 密码：
无效的密码： 密码是一个回文
重新输入新的 密码：
passwd：所有的身份验证令牌已经成功更新。
2、使用su命令进入hadoop1，并设置公钥私钥的密码
[root@localhost ~]# su - hadoop1
[hadoop1@localhost ~]$ ssh-keygen -t rsa
Generating public/private rsa key pair.
Enter file in which to save the key (/home/hadoop1/.ssh/id_rsa):
Created directory '/home/hadoop1/.ssh'.
Enter passphrase (empty for no passphrase):
Enter same passphrase again:
Your identification has been saved in /home/hadoop1/.ssh/id_rsa.
Your public key has been saved in /home/hadoop1/.ssh/id_rsa.pub.
The key fingerprint is:
SHA256:aRHJRQu69sm8qGY4Vt8rPlTlf9ta+1WAsuW120z0UVw hadoop1@localhost.localdomain
The key's randomart image is:
+---[RSA 2048]----+
| .o+o .E|
| .oo.. . o|
| . .oo o o..|
| ..o.= . +o|
| o.S ... . +|
| ...= . . .=.|
| o o .= ..o=|
| + o +... ..+|
| . +.oooo. .oo|
+----[SHA256]-----+
[hadoop1@localhost ~]$ ls .ssh/
id_rsa id_rsa.pub
3、将公钥使用scp上传至Hadoop2
[hadoop1@localhost ~]$ ssh-copy-id -i /home/hadoop1/.ssh/id_rsa hadoop2@192.168.200.105
......
........
Number of key(s) added: 1
Now try logging into the machine, with: "ssh 'hadoop2@192.168.200.105'"
and check to make sure that only the key(s) you wanted were added.
4，使用ssh命令进入hadoop2@网段，并在hadoop2中使用cat命令查看公钥的位置和公钥密文
[hadoop1@localhost ~]$ ssh hadoop2@192.168.200.105
Last login: Fri Aug 16 08:55:15 2019
[hadoop2@localhost ~]$ cat .ssh/
authorized_keys id_rsa id_rsa.pub known_hosts
[hadoop2@localhost ~]$ cat .ssh/authorized_keys
ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQDQj5eKD2XmixXnxf
JCISF0E/qZ9ZIIDfBBlGJ28VuITxwqU3AWTOn2+ukJu+XomgqDBoVu19
dfZ4BKHt4JBXghHoHMzQmgA09KaljKslB81kOrcYLLAd+B6y4BfkUPBIZ
kaCkeiWVQZqM49scZ/kzNnYioC7NI+0FgbmatsWWJ9nrh2clVnKklmHs
Gm7Cp4ZyEDec7eOL88/rCv3lhJguzIeDCQ1aALpWe6xAphnzYKE23zyhSQ
I8feyYiC+rW30zhhKmLqBbu9fAOjGujImraC9hcOIbYKjKm+q9XaZpyjaPoo
8+EhUQJGpzd+BXaWnNtcyCnMpED+13IoeFwSZmF hadoop1@localhost.
localdomain
5，登出，使用cat命令查看hadoop1的公钥与上传至hadoop2的公钥进行对比
[hadoop2@localhost ~]$ cat .ssh/authorized_keys
ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQDQj5eKD2XmixXnxf
JCISF0E/qZ9ZIIDfBBlGJ28VuITxwqU3AWTOn2+ukJu+XomgqDBoVu19
dfZ4BKHt4JBXghHoHMzQmgA09KaljKslB81kOrcYLLAd+B6y4BfkUPBIZ
kaCkeiWVQZqM49scZ/kzNnYioC7NI+0FgbmatsWWJ9nrh2clVnKklmHs
Gm7Cp4ZyEDec7eOL88/rCv3lhJguzIeDCQ1aALpWe6xAphnzYKE23zyhSQ
I8feyYiC+rW30zhhKmLqBbu9fAOjGujImraC9hcOIbYKjKm+q9XaZpyjaPoo
8+EhUQJGpzd+BXaWnNtcyCnMpED+13IoeFwSZmF hadoop1@localhost.
localdomain[hadoop2@localhost ~]$ 登出
Connection to 192.168.200.105 closed.
[hadoop1@localhost ~]$ cat .ssh/
authorized_keys id_rsa id_rsa.pub known_hosts
[hadoop1@localhost ~]$ cat .ssh/id_rsa.pub
ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQDQj5eKD2XmixXnxf
JCISF0E/qZ9ZIIDfBBlGJ28VuITxwqU3AWTOn2+ukJu+XomgqDBoVu19
dfZ4BKHt4JBXghHoHMzQmgA09KaljKslB81kOrcYLLAd+B6y4BfkUPBIZ
kaCkeiWVQZqM49scZ/kzNnYioC7NI+0FgbmatsWWJ9nrh2clVnKklmHs
Gm7Cp4ZyEDec7eOL88/rCv3lhJguzIeDCQ1aALpWe6xAphnzYKE23zyhS
QI8feyYiC+rW30zhhKmLqBbu9fAOjGujImraC9hcOIbYKjKm+q9XaZpyja
Poo8+EhUQJGpzd+BXaWnNtcyCnMpED+13IoeFwSZmF hadoop1@loc
alhost.localdomain
二、服务机2：Hadoop2实验
1.创建Hadoop2账户，并设置密码
[root@localhost ~]# useradd hadoop2
[root@localhost ~]# passwd hadoop2
更改用户 hadoop2 的密码 。
新的 密码：
无效的密码： 密码少于 8 个字符
重新输入新的 密码：
passwd：所有的身份验证令牌已经成功更新。
2、使用su命令进入hadoop2，并设置公钥私钥的密码
[root@localhost ~]# su - hadoop2
[hadoop2@localhost ~]$ ssh-keygen -t rsa
Generating public/private rsa key pair.
Enter file in which to save the key (/home/hadoop2/.ssh/id_rsa):
Created directory '/home/hadoop2/.ssh'.
Enter passphrase (empty for no passphrase):
Enter same passphrase again:
Your identification has been saved in /home/hadoop2/.ssh/id_rsa.
Your public key has been saved in /home/hadoop2/.ssh/id_rsa.pub.
The key fingerprint is:
SHA256:Tmc9M6I0fxQ5A/FnzbkxzmtbpKhPWZprPXqiRh+FJL8 hadoop2@localhost.localdomain
The key's randomart image is:
+---[RSA 2048]----+
| o. |
| .o.. o.|
| +*.o+o|
| .o*+ +|
| S + *o.+.|
| + *.oEX o.|
| o...Bo.o.|
| .++.= o|
| .o+++ o |
+----[SHA256]-----+
[hadoop2@localhost ~]$ ls .ssh/
id_rsa id_rsa.pub
3、将公钥使用scp上传至Hadoop1
[hadoop2@localhost ~]$ ssh-copy-id -i /home/hadoop2/.ssh/id_rsa hadoop1@192.168.200.111
.......
and check to make sure that only the key(s) you wanted were added.
4，使用ssh命令进入hadoop2@网段，并在hadoop2中使用cat命令查看公钥的位置和公钥密文
[hadoop1@localhost ~]$ ssh hadoop2@192.168.200.105
Last login: Fri Aug 16 08:55:15 2019
[hadoop2@localhost ~]$ cat .ssh/
authorized_keys id_rsa id_rsa.pub known_hosts
[hadoop2@localhost ~]$ cat .ssh/authorized_keys
ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQDQj5eKD2XmixXnxf
JCISF0E/qZ9ZIIDfBBlGJ28VuITxwqU3AWTOn2+ukJu+XomgqDBoVu19
dfZ4BKHt4JBXghHoHMzQmgA09KaljKslB81kOrcYLLAd+B6y4BfkUPBIZ
kaCkeiWVQZqM49scZ/kzNnYioC7NI+0FgbmatsWWJ9nrh2clVnKklmHs
Gm7Cp4ZyEDec7eOL88/rCv3lhJguzIeDCQ1aALpWe6xAphnzYKE23zyhSQ
I8feyYiC+rW30zhhKmLqBbu9fAOjGujImraC9hcOIbYKjKm+q9XaZpyjaPoo
8+EhUQJGpzd+BXaWnNtcyCnMpED+13IoeFwSZmF hadoop1@localhost.
localdomain
5，登出，使用cat命令查看hadoop1的公钥与上传至hadoop2的公钥进行对比
[hadoop2@localhost ~]$ cat .ssh/authorized_keys
ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQDQj5eKD2XmixXnxf
JCISF0E/qZ9ZIIDfBBlGJ28VuITxwqU3AWTOn2+ukJu+XomgqDBoVu19
dfZ4BKHt4JBXghHoHMzQmgA09KaljKslB81kOrcYLLAd+B6y4BfkUPBIZ
kaCkeiWVQZqM49scZ/kzNnYioC7NI+0FgbmatsWWJ9nrh2clVnKklmHs
Gm7Cp4ZyEDec7eOL88/rCv3lhJguzIeDCQ1aALpWe6xAphnzYKE23zyhSQ
I8feyYiC+rW30zhhKmLqBbu9fAOjGujImraC9hcOIbYKjKm+q9XaZpyjaPoo
8+EhUQJGpzd+BXaWnNtcyCnMpED+13IoeFwSZmF hadoop1@localhost.
localdomain[hadoop2@localhost ~]$ 登出
Connection to 192.168.200.105 closed.
[hadoop1@localhost ~]$ cat .ssh/
authorized_keys id_rsa id_rsa.pub known_hosts
[hadoop1@localhost ~]$ cat .ssh/id_rsa.pub
ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQDQj5eKD2XmixXnxf
JCISF0E/qZ9ZIIDfBBlGJ28VuITxwqU3AWTOn2+ukJu+XomgqDBoVu19
dfZ4BKHt4JBXghHoHMzQmgA09KaljKslB81kOrcYLLAd+B6y4BfkUPBIZ
kaCkeiWVQZqM49scZ/kzNnYioC7NI+0FgbmatsWWJ9nrh2clVnKklmHs
Gm7Cp4ZyEDec7eOL88/rCv3lhJguzIeDCQ1aALpWe6xAphnzYKE23zyhS
QI8feyYiC+rW30zhhKmLqBbu9fAOjGujImraC9hcOIbYKjKm+q9XaZpyja
Poo8+EhUQJGpzd+BXaWnNtcyCnMpED+13IoeFwSZmF hadoop1@loc
alhost.localdomain
二、服务机2：Hadoop2实验
1.创建Hadoop2账户，并设置密码
[root@localhost ~]# useradd hadoop2
[root@localhost ~]# passwd hadoop2
更改用户 hadoop2 的密码 。
新的 密码：
无效的密码： 密码少于 8 个字符
重新输入新的 密码：
passwd：所有的身份验证令牌已经成功更新。
2、使用su命令进入hadoop2，并设置公钥私钥的密码
[root@localhost ~]# su - hadoop2
[hadoop2@localhost ~]$ ssh-keygen -t rsa
Generating public/private rsa key pair.
Enter file in which to save the key (/home/hadoop2/.ssh/id_rsa):
Created directory '/home/hadoop2/.ssh'.
Enter passphrase (empty for no passphrase):
Enter same passphrase again:
Your identification has been saved in /home/hadoop2/.ssh/id_rsa.
Your public key has been saved in /home/hadoop2/.ssh/id_rsa.pub.
The key fingerprint is:
SHA256:Tmc9M6I0fxQ5A/FnzbkxzmtbpKhPWZprPXqiRh+FJL8 hadoop2@localhost.localdomain
The key's randomart image is:
+---[RSA 2048]----+
| o. |
| .o.. o.|
| +*.o+o|
| .o*+ +|
| S + *o.+.|
| + *.oEX o.|
| o...Bo.o.|
| .++.= o|
| .o+++ o |
+----[SHA256]-----+
[hadoop2@localhost ~]$ ls .ssh/
id_rsa id_rsa.pub
3、将公钥使用scp上传至Hadoop1
[hadoop2@localhost ~]$ ssh-copy-id -i /home/hadoop2/.ssh/id_rsa hadoop1@192.168.200.111
.......
............
Number of key(s) added: 1
Now try logging into the machine, with: "ssh 'hadoop1@192.168.200.111'"
and check to make sure that only the key(s) you wanted were added.
4，使用ssh命令进入hadoop1@网段，并在hadoop1中使用cat命令查看公钥的位置和公钥密文
[hadoop2@localhost ~]$ ssh hadoop1@192.168.200.111
Last login: Fri Aug 16 08:52:47 2019
[hadoop1@localhost ~]$ ls .ssh/
authorized_keys id_rsa id_rsa.pub known_hosts
[hadoop1@localhost ~]$ cat .ssh/authorized_keys
ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQC4/aqdjHqvj6dp
On+a9R+l9uvW9KI2ZEIJgKX+km2UE7OHdd/9txnKqbwUy85vRylD
phYacSxcivPFNHOyR17mt6w/jA6OiLiUvG0vsOl9/d2cDbba3gxpOJ
VWW9h9o2UQNqZ8FPPpkdH/uvlqZrTyuzVkQWWzV/TWe4WNtN
uk8IINx89Q7tTAXBSxR7CdMhyzQNAinQAAP0zm+/X8DG69mf8n
etNJzedBE+IYytr7JxCY657S8lO0qcPaQ10mJ237qgQXCV1JW4cb9
QoHtfiQ5ajhBKYzWNu/BkyT4rig2c2d0O2qTt3AVS6+5QEKEXZyFjV
53ZfXlgP+XLqliuYb hadoop2@localhost.localdomain
and check to make sure that only the key(s) you wanted were added.
4，使用ssh命令进入hadoop1@网段，并在hadoop1中使用cat命令查看公钥的位置和公钥密文
[hadoop2@localhost ~]$ ssh hadoop1@192.168.200.111
Last login: Fri Aug 16 08:52:47 2019
[hadoop1@localhost ~]$ ls .ssh/
authorized_keys id_rsa id_rsa.pub known_hosts
[hadoop1@localhost ~]$ cat .ssh/authorized_keys
ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQC4/aqdjHqvj6dp
On+a9R+l9uvW9KI2ZEIJgKX+km2UE7OHdd/9txnKqbwUy85vRylD
phYacSxcivPFNHOyR17mt6w/jA6OiLiUvG0vsOl9/d2cDbba3gxpOJ
VWW9h9o2UQNqZ8FPPpkdH/uvlqZrTyuzVkQWWzV/TWe4WNtN
uk8IINx89Q7tTAXBSxR7CdMhyzQNAinQAAP0zm+/X8DG69mf8n
etNJzedBE+IYytr7JxCY657S8lO0qcPaQ10mJ237qgQXCV1JW4cb9
QoHtfiQ5ajhBKYzWNu/BkyT4rig2c2d0O2qTt3AVS6+5QEKEXZyFjV
53ZfXlgP+XLqliuYb hadoop2@localhost.localdomain
5，登出，使用cat命令查看hadoop1的公钥与上传至hadoop2的公钥进行对比
[hadoop1@localhost ~]$ cat .ssh/authorized_keys
ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQC4/aqdjHqvj6dp
On+a9R+l9uvW9KI2ZEIJgKX+km2UE7OHdd/9txnKqbwUy85vRylD
phYacSxcivPFNHOyR17mt6w/jA6OiLiUvG0vsOl9/d2cDbba3gxpOJ
VWW9h9o2UQNqZ8FPPpkdH/uvlqZrTyuzVkQWWzV/TWe4WNtN
uk8IINx89Q7tTAXBSxR7CdMhyzQNAinQAAP0zm+/X8DG69mf8n
etNJzedBE+IYytr7JxCY657S8lO0qcPaQ10mJ237qgQXCV1JW4cb9
QoHtfiQ5ajhBKYzWNu/BkyT4rig2c2d0O2qTt3AVS6+5QEKEXZyFjV
53ZfXlgP+XLqliuYb hadoop2@localhost.localdomain
[hadoop1@localhost ~]$ 登出
Connection to 192.168.200.111 closed.
[hadoop2@localhost ~]$ ls .ssh/
authorized_keys id_rsa id_rsa.pub known_hosts
[hadoop2@localhost ~]$ cat .ssh/id_rsa.pub
ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQC4/aqdjHqvj6
dpOn+a9R+l9uvW9KI2ZEIJgKX+km2UE7OHdd/9txnKqbwUy85v
RylDphYacSxcivPFNHOyR17mt6w/jA6OiLiUvG0vsOl9/d2cDbba3
gxpOJVWW9h9o2UQNqZ8FPPpkdH/uvlqZrTyuzVkQWWzV/TWe
4WNtNuk8IINx89Q7tTAXBSxR7CdMhyzQNAinQAAP0zm+/X8DG
69mf8netNJzedBE+IYytr7JxCY657S8lO0qcPaQ10mJ237qgQXCV1
JW4cb9QoHtfiQ5ajhBKYzWNu/BkyT4rig2c2d0O2qTt3AVS6+5QEK
EXZyFjV53ZfXlgP+XLqliuYb hadoop2@localhost.localdomain
[hadoop1@localhost ~]$ cat .ssh/authorized_keys
ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQC4/aqdjHqvj6dp
On+a9R+l9uvW9KI2ZEIJgKX+km2UE7OHdd/9txnKqbwUy85vRylD
phYacSxcivPFNHOyR17mt6w/jA6OiLiUvG0vsOl9/d2cDbba3gxpOJ
VWW9h9o2UQNqZ8FPPpkdH/uvlqZrTyuzVkQWWzV/TWe4WNtN
uk8IINx89Q7tTAXBSxR7CdMhyzQNAinQAAP0zm+/X8DG69mf8n
etNJzedBE+IYytr7JxCY657S8lO0qcPaQ10mJ237qgQXCV1JW4cb9
QoHtfiQ5ajhBKYzWNu/BkyT4rig2c2d0O2qTt3AVS6+5QEKEXZyFjV
53ZfXlgP+XLqliuYb hadoop2@localhost.localdomain
[hadoop1@localhost ~]$ 登出
Connection to 192.168.200.111 closed.
[hadoop2@localhost ~]$ ls .ssh/
authorized_keys id_rsa id_rsa.pub known_hosts
[hadoop2@localhost ~]$ cat .ssh/id_rsa.pub
ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQC4/aqdjHqvj6
dpOn+a9R+l9uvW9KI2ZEIJgKX+km2UE7OHdd/9txnKqbwUy85v
RylDphYacSxcivPFNHOyR17mt6w/jA6OiLiUvG0vsOl9/d2cDbba3
gxpOJVWW9h9o2UQNqZ8FPPpkdH/uvlqZrTyuzVkQWWzV/TWe
4WNtNuk8IINx89Q7tTAXBSxR7CdMhyzQNAinQAAP0zm+/X8DG
69mf8netNJzedBE+IYytr7JxCY657S8lO0qcPaQ10mJ237qgQXCV1
JW4cb9QoHtfiQ5ajhBKYzWNu/BkyT4rig2c2d0O2qTt3AVS6+5QEK
EXZyFjV53ZfXlgP+XLqliuYb hadoop2@localhost.localdomain