【Linux】服务器间免密登录、免确认机器指纹

1.生成密钥

ssh-keygen -t rsa -C "<填写自己方便识别的注释>" -b 4096  没什么问题就执行三次空格。 
三次问题是1.填入生成密钥对的路径名字。2 填入自定义passphrsa。3确认。

静默模式，不需要回车生成密钥

ssh-keygen -t rsa -N '' -f id_rsa -q 

• -N:是指密码为空；
• -f:id_rsa是指保存文件为~/.ssh/id_rsa和~/.ssh/id_rsa.pub
• -q:指静默模式, 不输出显示

 [root@localhost home]# ssh-keygen -t rsa -C "********" -b 4096
 Generating public/private rsa key pair.
 Enter file in which to save the key (/root/.ssh/id_rsa):
 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:oQYIN3KUkPmnCn0LrC25h5L0yVpiIvoHUgawDuyCKuE **************
 The key's randomart image is:
 +---[RSA 4096]----+
 |*==.             |
 |=*.o             |
 |o+. .   .        |
 |= + .. . .       |
 |+B o  o S        |
 |*o* ..           |
 |BEo=..           |
 |# =+o            |
 |+*o.             |
 +----[SHA256]-----+

2.生成的公钥和私钥在/root/.ssh目录下

 [root@localhost .ssh]# pwd
 /root/.ssh
 [root@localhost .ssh]# ls -l
 总用量 12
 -rw-------. 1 root root 3247 9月  19 10:00 id_rsa       #私钥
 -rw-r--r--. 1 root root  746 9月  19 10:00 id_rsa.pub   #公钥
 -rw-r--r--. 1 root root  174 9月  18 16:58 known_hosts

3.将公钥id_rsa.pub复制到远程主机/root/.ssh/文件中，并且重命名为authorized_keys。

• scp  /root/.ssh/id_rsa.pub   root@远程ip:/root/.ssh/authorized_keys

或

• ssh-copy-id  -i  ~/.ssh/id_rsa.pub root@远程ip

验证密码即可

4.连接

• ssh 远程ip

5.免确认机器指纹（不加入known_hosts）

• ssh -o StrictHostKeyChecking=no 远程ip