SSH免密码登录Linux服务器

服务器：Ubuntu 16.04 x64

本机：Ubuntu 16.04 x64

1、查看本机是否存在密钥对

username@ubuntu:~$ cd ~/.sshusername@ubuntu:~/.ssh$ lsid_rsa  id_rsa.pub

2、如果不存在，则首先生成密钥对

username@ubuntu:~$ ssh-keygen -t rsaGenerating public/private rsa key pair.Enter file in which to save the key (/home/username/.ssh/id_rsa): Enter passphrase (empty for no passphrase): Enter same passphrase again: Your identification has been saved in /home/username/.ssh/id_rsa.Your public key has been saved in /home/username/.ssh/id_rsa.pub.The key fingerprint is:SHA256:xxxxxxxxxxxxxxxxxxxx username@ubuntuThe key's randomart image is:+---[RSA 2048]----+|                 ||                 ||                 ||        A        ||    randomart    ||      image      ||                 ||                 ||                 |+----[SHA256]-----+

3、将本机公钥上传到远程服务器

username@ubuntu:~$ scp ~/.ssh/id_rsa.pub root@romote_server_IP:/root/The authenticity of host 'romote_server_IP (romote_server_IP)' can't be established.ECDSA key fingerprint is SHA256:xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx.Are you sure you want to continue connecting (yes/no)? yesWarning: Permanently added 'romote_server_IP' (ECDSA) to the list of known hosts.root@romote_server_IP's password: xxxxxxxxxxid_rsa.pub                                    100%  390     0.4KB/s   00:00    username@ubuntu:~$ 

4、登录远程服务器，将本机公钥添加到远程服务器的authorized_keys中，如果服务器中用户目录下不存在.ssh文件夹和authorized_keys文件，则新建并修改权限

username@ubuntu:~$ ssh root@romote_server_IProot@romote_server_IP's password: Welcome to Ubuntu 16.04.x LTS (GNU/Linux x.x.x-xx-generic x86_64) * Documentation:  https://help.ubuntu.com * Management:     https://landscape.canonical.com * Support:        https://ubuntu.com/advantagexx packages can be updated.xx updates are security updates.Last login: last_login_time from xxx.xx.xx.xxxroot@remote_server:~# ls -a.   .bash_history  .cache    .viminfo    id_rsa.pub..  .bashrc        .profile  .wget-hsts  root@remote_server:~# mkdir .sshroot@remote_server:~# chmod 700 ~/.sshroot@remote_server:~# touch ~/.ssh/authorized_keysroot@remote_server:~# chmod 600 ~/.ssh/authorized_keysroot@remote_server:~# cat ~/id_rsa.pub >> ~/.ssh/authorized_keysroot@remote_server:~# 

5、本机配置远程服务器别名代替IP地址

username@ubuntu:~$ vim ~/.ssh/configHost remote_server_aliasHostName xxx.xxx.xx.xxPort 22User remote_server_usernamePreferredAuthentications publickeyIdentityFile ~/.ssh/id_rsa~                                                                               ~                                                                                                                                                   :wqusername@ubuntu:~$ ssh remote_server_aliasWelcome to Ubuntu 16.04.x LTS (GNU/Linux x.x.x-xx-generic x86_64) * Documentation:  https://help.ubuntu.com * Management:     https://landscape.canonical.com * Support:        https://ubuntu.com/advantagexx packages can be updated.xx updates are security updates.Last login: last_login_time from xxx.xx.xx.xxxroot@remote_server:~#