Linux 生成pem文件用于免密登录
Linux命令讲解
生成密钥对，在远程机器生成.pem文件：
$ ssh-keygen -t rsa -b 2048 -v
直接确认下一步，查看生成的密钥对：
$ ls ~/.ssh/
生成了id_rsa和id_rsa.pub
将私钥重命名至id_rsa.pem：
$ mv ~/.ssh/id_rsa ~/.ssh/id_rsa.pem
修改~/.ssh/目录权限：
$ chmod 700 ~/.ssh/
将id_rsa.pub文件内容重定向至authorized_keys文件：
$ cat ~/.ssh/id_rsa.pub >> ~/.ssh/authorized_keys
修改authorized_keys文件权限：
$ chmod 600 ~/.ssh/authorized_keys
修改ssh配置文件
$ sudo vim /etc/ssh/sshd_config
添加以下几行
RSAAuthentication yes
PubkeyAuthentication yes#修改一下，禁用密码登录
PasswordAuthentication no#可选项，禁用密码登录
AuthorizedKeysFile %h/.ssh/authorized_keys
重启ssh服务：
$ sudo service sshd restart
将id_rsa.pem文件拷贝至本机，即可通过登录工具，利用私钥进行登录。
总体Shell脚本如下
ssh-keygen -t rsa -b 2048 -v
回车到结束
ls ~/.ssh/
mv ~/.ssh/id_rsa ~/.ssh/id_rsa.pem
chmod 700 ~/.ssh/
cat ~/.ssh/id_rsa.pub >> ~/.ssh/authorized_keys
chmod 600 ~/.ssh/authorized_keysvim /etc/ssh/sshd_configAuthorizedKeysFile .ssh/authorized_keys
sudo vim /etc/ssh/sshd_config
sudo service sshd restart
