本文Linux系统为CentOS Linux 7。
ssh-keygen命令生成公钥和私钥，名字分别是“id_rsa.pub”和“id_rsa”，公钥发送到服务器上，私钥本地使用。
远程是在“~/.ssh/authrized_key”文件中，本地是在“%usersprofile%/.ssh/”目录
密钥生成命令
#ssh-keygen -t rsa
操作记录
[root@learnshell ~]# ssh-keygen -t rsa
Generating public/private rsa key pair.
Enter file in which to save the key (/root/.ssh/id_rsa): 密钥文件存储路径，直接回车使用默认
Created directory '/root/.ssh'.
Enter passphrase (empty for no passphrase): 密钥文件密码，直接回车使用不设置
Enter same passphrase again:
[root@learnshell ~]# cd /root/.ssh/
[root@learnshell .ssh]# ls
id_rsa id_rsa.pub
密钥上传
使用“ssh-copy-id”命令上传
[root@learnshell .ssh]# ssh-copy-id -i ~/.ssh/id_rsa.pub root@192.168.2.106
/usr/bin/ssh-copy-id: INFO: Source of key(s) to be installed: "/root/.ssh/id_rsa.pub"
/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@192.168.2.106's password:
Number of key(s) added: 1
Now try logging into the machine, with: "ssh 'root@127.0.0.1'"
and check to make sure that only the key(s) you wanted were added.
使用其他工具将文件添加至authorized_keys文件末尾
上传 id_rsa.pub文件后，使用重定向符追加至authorized_keys文件末尾
[root@learnshell .ssh]$cat id_rsa.pub >> authorized_keys
[root@learnshell .ssh]# cat ~/.ssh/authorized_keys
ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAxxxxxAwmvid5q8naRwUohZTHYa/BVP0vxhdcav2TI0b4YRFIPdhd/kNprqV1HgQQQdbOdHwqMXepM68B+n8ukt7JFyfEF1IHML8hQy27hoJHwUo2fNJI8N8w5mO6glG+GxQciPP4dAJ+UAdd1qxtj3QKhYvRxxxxxoqDKOvkkvTp0brHz0vYDNV8Fx6MELMz4rSdcQPFZhSeZ9P5dJCcW6hdPBcUnKKMY8RtadPAPw+AGINexxxxxXbwEcqLxNRpW/DHG5E14Voxp4lgndeWOt8CJNWgWrp3mAYhf9sXvtICTdnhZA8Hjs0ckUV6tabfUlKsyj1gKEgSymP root@learnshell.local
免密登录使用
命令行使用
将id_rsa拷贝至“%usersprofile%/.ssh/”目录，直接使用“ssh root@192.168.2.106”登录
SecureCRT使用
SecureCRT，新建会话，协议选择“ssh2”，其他根据实际情况填写，选中“PublicKey”，点击左侧的“Properties”，浏览生成的私钥保存。
注意，使用私钥登录需要去掉“Password”前的勾。
