记录linux的SSH免密登录

﹏ヽ暗。殇╰゛Y 2022-05-30 06:29 108阅读 0赞

当我们从一台机器通过ssh登录到另外一台机器的时候，总是会要求输入登录密码，为了不输入密码登录，ssh提供了免密码登录，也就是所谓的公钥登录，公钥登录就是用户把自己的公钥发送到远程主机上，当远程主机需要登录的时候会做一个验签名的操作，如果签名通过那么就不需要密码登录啦。具体操作如下。

1、生成rsa的秘钥对

进入当前用户的根目录，执行ssh-keygen -t rsa，输入四个回车就行，不需要写啥..

[hadoop@hadoop ~]$ cd
    [hadoop@hadoop ~]$ ssh-keygen  -t rsa
    Generating public/private rsa key pair.
    Enter file in which to save the key (/home/hadoop/.ssh/id_rsa): 
    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:
    48:28:73:09:f6:8a:03:d0:ab:37:2d:34:65:23:18:89 hadoop@hadoop.madmant.com
    The key's randomart image is:
    +--[ RSA 2048]----+
    |+=o              |
    |E.oo+o           |
    |. o==..          |
    |..+= . .         |
    |oo.o  . S        |
    |..+ .            |
    | . o             |
    |                 |
    |                 |
    +-----------------+
    [hadoop@hadoop ~]$

命令执行完之后会在当前目录的.ssh目录下生成两个文件，就是私钥和公钥。

[hadoop@hadoop .ssh]$ pwd
    /home/hadoop/.ssh
    [hadoop@hadoop .ssh]$ ll
    total 8
    -rw------- 1 hadoop hadoop 1675 Mar  6 05:47 id_rsa
    -rw-r--r-- 1 hadoop hadoop  407 Mar  6 05:47 id_rsa.pub
    [hadoop@hadoop .ssh]$

然后再/home/hadoop/.ssh目录下执行发送秘钥命令

[hadoop@hadoop .ssh]$ ssh-copy-id hadoop.madmant.com

这里的hadoop.madmant.com就是主机名，也可以是ip，然后就可以测试ssh登录看看还需不需要密码。