Hadoop基础教程-第1章环境安装配置（1.6 SSH免密登录）

程裕强

发布于 2022-05-06 18:26:59

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发布于 2022-05-06 18:26:59

文章被收录于专栏：大数据学习笔记大数据学习笔记

第1章环境安装配置

1.6 SSH免密登录

1、XShell的一个技巧

当多台虚拟机需要执行相同命令时，可以单击XShell右下角的“三条横杠”按钮，选择“全部会话”，这时XShell下方的输入框将显示提示“发送文本到当前XShell窗口的全部会话”

比如在XShell下方输入框输入data命令

回车后，将该date命令同时发送到node1、node2和node3。这时可以看到其他两个会话标签多了个叹号提示符。

查看node2执行情况

查询node3执行情况

2、生成RSA秘钥对

在XShell下方输入框中输入命令ssh-keygen -t rsa，然后回车执行。再回车3次，即可生成RSA秘钥对

查看密钥对文件

[root@node1 ~]# ls .ssh
id_rsa  id_rsa.pub

id_rsa：私钥
id_rsa.pub：公钥

3、将每个节点的公钥拷贝到authorized_keys

可以通过命令ssh-copy-id，将本机公钥复制到其他节点的authorized_keys目录，这样本机即可免秘钥登录其他节点。为了操作方便，我们通过XShell执行下方输入框执行命令即可：

ssh-copy-id node1

按照提示输入“yes”和密码，即可将node1的公钥复制到node1、node2和node3节点。（复制本机，可以实现免密登录本机）

然后再通过XShell分别执行：

ssh-copy-id node2
ssh-copy-id node3

通过XShell执行三条ssh-copy-id命令，实际上就是分别在node1、node2和node3节点执行。下面是命令执行信息： （1）node1 ssh-copy-id node1 ssh-copy-id node2 ssh-copy-id node3

[root@node1 ~]# ssh-copy-id node1
The authenticity of host 'node1 (192.168.80.131)' can't be established.
ECDSA key fingerprint is e2:9a:7d:70:25:24:45:11:97:12:35:e0:45:4c:64:31.
Are you sure you want to continue connecting (yes/no)? yes
/usr/bin/ssh-copy-id: INFO: attempting to log in with the new key(s), to filter out any that are already installed
/usr/bin/ssh-copy-id: INFO: 1 key(s) remain to be installed -- if you are prompted now it is to install the new keys
root@node1's password: 

Number of key(s) added: 1

Now try logging into the machine, with:   "ssh 'node1'"
and check to make sure that only the key(s) you wanted were added.

[root@node1 ~]# ssh-copy-id node2
The authenticity of host 'node2 (192.168.80.132)' can't be established.
ECDSA key fingerprint is e2:9a:7d:70:25:24:45:11:97:12:35:e0:45:4c:64:31.
Are you sure you want to continue connecting (yes/no)? yes
/usr/bin/ssh-copy-id: INFO: attempting to log in with the new key(s), to filter out any that are already installed
/usr/bin/ssh-copy-id: INFO: 1 key(s) remain to be installed -- if you are prompted now it is to install the new keys
root@node2's password: 

Number of key(s) added: 1

Now try logging into the machine, with:   "ssh 'node2'"
and check to make sure that only the key(s) you wanted were added.

[root@node1 ~]# ssh-copy-id node3
The authenticity of host 'node3 (192.168.80.133)' can't be established.
ECDSA key fingerprint is e2:9a:7d:70:25:24:45:11:97:12:35:e0:45:4c:64:31.
Are you sure you want to continue connecting (yes/no)? yes
/usr/bin/ssh-copy-id: INFO: attempting to log in with the new key(s), to filter out any that are already installed
/usr/bin/ssh-copy-id: INFO: 1 key(s) remain to be installed -- if you are prompted now it is to install the new keys
root@node3's password: 

Number of key(s) added: 1

Now try logging into the machine, with:   "ssh 'node3'"
and check to make sure that only the key(s) you wanted were added.

[root@node1 ~]#

（2）node2 ssh-copy-id node1 ssh-copy-id node2 ssh-copy-id node3

[root@node2 ~]# ssh-copy-id node1
The authenticity of host 'node1 (192.168.80.131)' can't be established.
ECDSA key fingerprint is e2:9a:7d:70:25:24:45:11:97:12:35:e0:45:4c:64:31.
Are you sure you want to continue connecting (yes/no)? yes
/usr/bin/ssh-copy-id: INFO: attempting to log in with the new key(s), to filter out any that are already installed
/usr/bin/ssh-copy-id: INFO: 1 key(s) remain to be installed -- if you are prompted now it is to install the new keys
root@node1's password: 

Number of key(s) added: 1

Now try logging into the machine, with:   "ssh 'node1'"
and check to make sure that only the key(s) you wanted were added.

[root@node2 ~]# ssh-copy-id node2
The authenticity of host 'node2 (192.168.80.132)' can't be established.
ECDSA key fingerprint is e2:9a:7d:70:25:24:45:11:97:12:35:e0:45:4c:64:31.
Are you sure you want to continue connecting (yes/no)? yes
/usr/bin/ssh-copy-id: INFO: attempting to log in with the new key(s), to filter out any that are already installed
/usr/bin/ssh-copy-id: INFO: 1 key(s) remain to be installed -- if you are prompted now it is to install the new keys
root@node2's password: 

Number of key(s) added: 1

Now try logging into the machine, with:   "ssh 'node2'"
and check to make sure that only the key(s) you wanted were added.

[root@node2 ~]# ssh-copy-id node3
The authenticity of host 'node3 (192.168.80.133)' can't be established.
ECDSA key fingerprint is e2:9a:7d:70:25:24:45:11:97:12:35:e0:45:4c:64:31.
Are you sure you want to continue connecting (yes/no)? yes
/usr/bin/ssh-copy-id: INFO: attempting to log in with the new key(s), to filter out any that are already installed
/usr/bin/ssh-copy-id: INFO: 1 key(s) remain to be installed -- if you are prompted now it is to install the new keys
root@node3's password: 

Number of key(s) added: 1

Now try logging into the machine, with:   "ssh 'node3'"
and check to make sure that only the key(s) you wanted were added.

[root@node2 ~]#

（3）node3 ssh-copy-id node1 ssh-copy-id node2 ssh-copy-id node3

[root@node3 ~]# ssh-copy-id node1
The authenticity of host 'node1 (192.168.80.131)' can't be established.
ECDSA key fingerprint is e2:9a:7d:70:25:24:45:11:97:12:35:e0:45:4c:64:31.
Are you sure you want to continue connecting (yes/no)? yes
/usr/bin/ssh-copy-id: INFO: attempting to log in with the new key(s), to filter out any that are already installed
/usr/bin/ssh-copy-id: INFO: 1 key(s) remain to be installed -- if you are prompted now it is to install the new keys
root@node1's password: 

Number of key(s) added: 1

Now try logging into the machine, with:   "ssh 'node1'"
and check to make sure that only the key(s) you wanted were added.

[root@node3 ~]# ssh-copy-id node2
The authenticity of host 'node2 (192.168.80.132)' can't be established.
ECDSA key fingerprint is e2:9a:7d:70:25:24:45:11:97:12:35:e0:45:4c:64:31.
Are you sure you want to continue connecting (yes/no)? yes
/usr/bin/ssh-copy-id: INFO: attempting to log in with the new key(s), to filter out any that are already installed
/usr/bin/ssh-copy-id: INFO: 1 key(s) remain to be installed -- if you are prompted now it is to install the new keys
root@node2's password: 

Number of key(s) added: 1

Now try logging into the machine, with:   "ssh 'node2'"
and check to make sure that only the key(s) you wanted were added.

[root@node3 ~]# ssh-copy-id node3
The authenticity of host 'node3 (192.168.80.133)' can't be established.
ECDSA key fingerprint is e2:9a:7d:70:25:24:45:11:97:12:35:e0:45:4c:64:31.
Are you sure you want to continue connecting (yes/no)? yes
/usr/bin/ssh-copy-id: INFO: attempting to log in with the new key(s), to filter out any that are already installed
/usr/bin/ssh-copy-id: INFO: 1 key(s) remain to be installed -- if you are prompted now it is to install the new keys
root@node3's password: 

Number of key(s) added: 1

Now try logging into the machine, with:   "ssh 'node3'"
and check to make sure that only the key(s) you wanted were added.

[root@node3 ~]#

4、测试免密登录

[root@node1 ~]# ssh node1
Last login: Fri Jul 21 23:13:10 2017 from node1
[root@node1 ~]# ls .ssh
authorized_keys  id_rsa  id_rsa.pub  known_hosts
[root@node1 ~]# ssh node2
Last login: Fri Jul 21 23:13:18 2017 from node2
[root@node2 ~]# ssh node3
Last login: Fri Jul 21 23:16:03 2017 from node3
[root@node3 ~]# ssh node2
Last login: Fri Jul 21 23:31:43 2017 from node1
[root@node2 ~]# ssh node1
Last login: Fri Jul 21 23:16:06 2017 from node3
[root@node1 ~]#

[root@node1 ~]# ll .ssh
total 16
-rw------- 1 root root 1176 Jul 21 23:14 authorized_keys
-rw------- 1 root root 1679 Jul 21 23:14 id_rsa
-rw-r--r-- 1 root root  392 Jul 21 23:14 id_rsa.pub
-rw-r--r-- 1 root root  546 Jul 21 23:15 known_hosts

cat .ssh/authorized_keys

[root@node1 ~]# cat .ssh/authorized_keys 
ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQC6II3oKg4lI8LWTPBQXVmtRxO/9t+Fen1Ful2wpfAiJfv2ysUxI7hvVKedGdmgmzqhsbpyhC9wadS69WQPS4Kxi81ZbDbCzQtzMh7tlMe1TXsIkBzEMHlskNzwb0ZRdknnF6RXHnfwDBG2WBvs9r8WxmWtm/RzAp0j03RFHmW6IevXu4xuwi1jDJftMjJfkXD9YKiPGlwBBzZ69AWT++KlZe743Dt/1JKGcxNgCMAtjpmFTPPBaKpYEb1GFP1A1StKABFk6QMoI1T442lc5C6W7V98kSWYZdutXoLtrymzQmrERJSjV/31hs27FbzJ93kj42/Nyfj8QlFpNfPZOI6l root@node1
ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQD1ZDljkN4isOzG90Iyv8yMomZFcfHYK2JghV3ZD5Fc/RA10502V4PMpTSYcePAylFAnuFmzYkCKY6HHhM0hONL7rqTvwpsmRQ4llc2eaxj8GB/87sYQQm+GAe6/QWDCh4G461pKo5CxhR5L7yAT2/Q8ddFuGfaBUp8GN+zfpBBgPUnJid1F8YavJJTZPAMqZMcfAnbyb++AZ6+RtOzfbyehmYo2Q/a5maBtK4s80N8XT7yMcAzk+B5DUOuxRXUtjcbbZqn94o4NUfWB3Qm+OWWr+yL9fW2tQdD4iLR1lCS33IikyN1/q++jfNW6yzWlWZUSrqTst6pn+JhxmFmMeId root@node3
ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQDTtAK1vI6hXvucGd+98Naqb8r/LaAIOzbmRGP/yVma2R9LLZrPY+++NkQHx9CGEEoJUABQVAOAerWepkxy65Rfn0i6KkcgPAS/ItaxnVB7+fDraq0aOFrwh+WYC3BK/2ns+3b0dweYuHTYpAhpbWuyAUQA4gSSiFyVuzk8ycQ1b7oe4hPrmamb4+T1B8H4aDgg9shreH7i4OIXAQLPQlZmNdyiX+HnxtuREEvhqGH+JquIe/I/AfB9KiLaE3e/52dOmBl5rzr8GcncqUese3L7dVwxBUNWFA/wmwuWRAQhY/GwSAp/67ZnwpNs1sBSK6D+1d2XNgzmpfWK18Ilk6fb root@node2

cat .ssh/known_hosts

[root@node1 ~]# cat .ssh/known_hosts 
node1,192.168.80.131 ecdsa-sha2-nistp256 AAAAE2VjZHNhLXNoYTItbmlzdHAyNTYAAAAIbmlzdHAyNTYAAABBBA+9ht7NXrQyz1cD2YY4w17BEMnM0yZjG2VeVFIztrmusVnFFqJNmvHsxVHWJNnhQeFQPJ0GvPL7I4WB34pmz5E=
node2,192.168.80.132 ecdsa-sha2-nistp256 AAAAE2VjZHNhLXNoYTItbmlzdHAyNTYAAAAIbmlzdHAyNTYAAABBBA+9ht7NXrQyz1cD2YY4w17BEMnM0yZjG2VeVFIztrmusVnFFqJNmvHsxVHWJNnhQeFQPJ0GvPL7I4WB34pmz5E=
node3,192.168.80.133 ecdsa-sha2-nistp256 AAAAE2VjZHNhLXNoYTItbmlzdHAyNTYAAAAIbmlzdHAyNTYAAABBBA+9ht7NXrQyz1cD2YY4w17BEMnM0yZjG2VeVFIztrmusVnFFqJNmvHsxVHWJNnhQeFQPJ0GvPL7I4WB34pmz5E=
[root@node1 ~]#

5、退出ssh登录

exit命令退出

[root@node1 ~]# exit
logout
Connection to node1 closed.
[root@node2 ~]#

快捷键ctl+d退出

[root@node2 ~]# logout
Connection to node2 closed.
[root@node3 ~]# logout
Connection to node3 closed.
[root@node2 ~]# logout
Connection to node2 closed.
[root@node1 ~]#

6、免密登录脚本

（1）脚本内容

# !/bin/bash
SERVERS="node1 node2 node3"
PASSWORD=123456
auto_gen_ssh_key() {
    expect -c "set timeout -1;
        spawn ssh-keygen;
        expect {
            *(/root/.ssh/id_rsa)* {send -- \r;exp_continue;}
                *passphrase)* {send -- \r;exp_continue;}
                *again* {send -- \r;exp_continue;}
                *(y/n)* {send -- y\r;exp_continue;}
                *password:* {send -- $PASSWORD\r;exp_continue;}
                eof         {exit 0;}
        }";
}

auto_ssh_copy_id() {
        expect -c "set timeout -1;
        spawn ssh-copy-id $1;
        expect {
            *(yes/no)*  {send -- yes\r;exp_continue;}
            *password:* {send -- $2\r;exp_continue;}
            eof         {exit 0;}
        }";
}

auto_copy_id_to_all() {
        for SERVER in $SERVERS
    do
         auto_ssh_copy_id $SERVER $PASSWORD
    done
}
yum install -y expect
auto_gen_ssh_key
auto_copy_id_to_all

（2）创建脚本文件，填入上面内容

[root@node3 ~]# vi ssh.sh

（3）设置脚本可执行

[root@node3 ~]# chmod +x ssh.sh 
[root@node3 ~]# ll
总用量 8
-rw-------. 1 root root 1260 8月  28 2021 anaconda-ks.cfg
-rwxr-xr-x  1 root root  780 8月  28 10:37 ssh.sh
[root@node3 ~]#

（4）执行脚本

[root@node3 ~]# ./ssh.sh 
已加载插件：fastestmirror
Loading mirror speeds from cached hostfile
 * base: mirrors.aliyun.com
 * extras: mirrors.aliyun.com
 * updates: mirrors.aliyun.com
正在解决依赖关系
--> 正在检查事务
---> 软件包 expect.x86_64.0.5.45-14.el7_1 将被 安装
--> 正在处理依赖关系 libtcl8.5.so()(64bit)，它被软件包 expect-5.45-14.el7_1.x86_64 需要
--> 正在检查事务
---> 软件包 tcl.x86_64.1.8.5.13-8.el7 将被 安装
--> 解决依赖关系完成

依赖关系解决

===================================================================================================
 Package              架构                 版本                           源                  大小
===================================================================================================
正在安装:
 expect               x86_64               5.45-14.el7_1                  base               262 k
为依赖而安装:
 tcl                  x86_64               1:8.5.13-8.el7                 base               1.9 M

事务概要
===================================================================================================
安装  1 软件包 (+1 依赖软件包)

总下载量：2.1 M
安装大小：4.9 M
Downloading packages:
(1/2): expect-5.45-14.el7_1.x86_64.rpm                                      | 262 kB  00:00:00     
(2/2): tcl-8.5.13-8.el7.x86_64.rpm                                          | 1.9 MB  00:00:01     
---------------------------------------------------------------------------------------------------
总计                                                               1.4 MB/s | 2.1 MB  00:00:01     
Running transaction check
Running transaction test
Transaction test succeeded
Running transaction
  正在安装    : 1:tcl-8.5.13-8.el7.x86_64                                                                                                         1/2 
  正在安装    : expect-5.45-14.el7_1.x86_64                                                                                                       2/2 
  验证中      : 1:tcl-8.5.13-8.el7.x86_64                                                                                                         1/2 
  验证中      : expect-5.45-14.el7_1.x86_64                                                                                                       2/2 

已安装:
  expect.x86_64 0:5.45-14.el7_1                                                                                                                       

作为依赖被安装:
  tcl.x86_64 1:8.5.13-8.el7                                                                                                                           

完毕！
spawn ssh-keygen
Generating public/private rsa key pair.
Enter file in which to save the key (/root/.ssh/id_rsa): 
Created directory '/root/.ssh'.
Enter passphrase (empty for no passphrase): 
Enter same passphrase again: 
Your identification has been saved in /root/.ssh/id_rsa.
Your public key has been saved in /root/.ssh/id_rsa.pub.
The key fingerprint is:
SHA256:KcSgIBxGPk4/9QvRvdOL7Gk8G72q/5+u7LkyKrbi/Bs root@node3
The key's randomart image is:
+---[RSA 2048]----+
|=+. .            |
|+o . o. .        |
| +.  oo. .       |
|o o ..o  .o      |
| . o ...So .     |
|    . ..o + .    |
|     E ..+ o     |
|  .. o. .*+ o .  |
|  .o+++o=*OO=+   |
+----[SHA256]-----+
spawn ssh-copy-id node1
/usr/bin/ssh-copy-id: INFO: Source of key(s) to be installed: "/root/.ssh/id_rsa.pub"
The authenticity of host 'node1 (192.168.9.101)' can't be established.
ECDSA key fingerprint is SHA256:rkytFGgctle6A5MUemlUxQBCVRoH+LC/QlLipa7gzG4.
ECDSA key fingerprint is MD5:0c:20:40:c0:1d:ea:00:bc:8e:45:8a:76:62:27:c8:3b.
Are you sure you want to continue connecting (yes/no)? yes
/usr/bin/ssh-copy-id: INFO: attempting to log in with the new key(s), to filter out any that are already installed
/usr/bin/ssh-copy-id: INFO: 1 key(s) remain to be installed -- if you are prompted now it is to install the new keys
root@node1's password: 

Number of key(s) added: 1

Now try logging into the machine, with:   "ssh 'node1'"
and check to make sure that only the key(s) you wanted were added.

spawn ssh-copy-id node2
/usr/bin/ssh-copy-id: INFO: Source of key(s) to be installed: "/root/.ssh/id_rsa.pub"
The authenticity of host 'node2 (192.168.9.102)' can't be established.
ECDSA key fingerprint is SHA256:rkytFGgctle6A5MUemlUxQBCVRoH+LC/QlLipa7gzG4.
ECDSA key fingerprint is MD5:0c:20:40:c0:1d:ea:00:bc:8e:45:8a:76:62:27:c8:3b.
Are you sure you want to continue connecting (yes/no)? yes
/usr/bin/ssh-copy-id: INFO: attempting to log in with the new key(s), to filter out any that are already installed
/usr/bin/ssh-copy-id: INFO: 1 key(s) remain to be installed -- if you are prompted now it is to install the new keys
root@node2's password: 

Number of key(s) added: 1

Now try logging into the machine, with:   "ssh 'node2'"
and check to make sure that only the key(s) you wanted were added.

spawn ssh-copy-id node3
/usr/bin/ssh-copy-id: INFO: Source of key(s) to be installed: "/root/.ssh/id_rsa.pub"
The authenticity of host 'node3 (192.168.9.103)' can't be established.
ECDSA key fingerprint is SHA256:rkytFGgctle6A5MUemlUxQBCVRoH+LC/QlLipa7gzG4.
ECDSA key fingerprint is MD5:0c:20:40:c0:1d:ea:00:bc:8e:45:8a:76:62:27:c8:3b.
Are you sure you want to continue connecting (yes/no)? yes
/usr/bin/ssh-copy-id: INFO: attempting to log in with the new key(s), to filter out any that are already installed
/usr/bin/ssh-copy-id: INFO: 1 key(s) remain to be installed -- if you are prompted now it is to install the new keys
root@node3's password: 

Number of key(s) added: 1

Now try logging into the machine, with:   "ssh 'node3'"
and check to make sure that only the key(s) you wanted were added.

[root@node3 ~]#

（5）测试免密登录

[root@node3 ~] ssh node1
Last login: Sat Aug 28 10:35:43 2021 from 192.168.9.1
[root@node1 ~]# exit
登出
Connection to node1 closed.
[root@node3 ~]# ssh node2
Last login: Sat Aug 28 10:36:01 2021 from 192.168.9.1
[root@node2 ~]# exit
登出
Connection to node2 closed.
[root@node3 ~]# ssh node3
Last login: Sat Aug 28 10:36:07 2021 from 192.168.9.1
[root@node3 ~]# exit
登出
Connection to node3 closed.
[root@node3 ~]#

（6）然后将该脚本复制到node1和node2,执行一遍。

[root@node3 ~]# scp ssh.sh node1:/root
ssh.sh                                                                                                              100%  780   212.1KB/s   00:00    
[root@node3 ~]# scp ssh.sh node2:/root
ssh.sh                                                                                                              100%  780   197.4KB/s   00:00    
[root@node3 ~]#