如何创建公钥私钥对

使用SSH协议下载，通过公钥认证的方式避免输入密码：

客户在本机上生成公钥私钥对（使用命令"ssh-keygen"，一直回车，不用输入口令），如下图所示：

$ ssh-keygen                                                                                                                                                           

Generating public/private rsa key pair.
Enter file in which to save the key (/home/lordyung/.ssh/id_rsa):
Created directory '/home/lordyung/.ssh'.
Enter passphrase (empty for no passphrase):
Enter same passphrase again:
Your identification has been saved in /home/lordyung/.ssh/id_rsa.
Your public key has been saved in /home/lordyung/.ssh/id_rsa.pub.
The key fingerprint is:
c2:a5:f4:f6:82:f8:1d:4e:a7:24:d3:7f:34:c9:e3:d6 lordyung@cm88
The key's randomart image is:
+--[ RSA 2048]----+
|                 |
|                 |
|      . .        |
|     o +         |
|      + S  . .   |
|     . = .  *    |
|    . + * oo +   |
|     . B *  + E  |
|      . + .o     |
+-----------------+

成功后会在~/.ssh/目录下生成id_rsa.pub和id_rsa 两个文件。

注意事项:

1. 公钥和私钥文件一定要保存好，不能删除。最好备份这两个文件，误删除时可恢复。
2. 客户下载代码时，如果命令行前面加了sudo,那么生成公钥的命令 ssh-keygen 前面也要加sudo（也就是要么都加sudo,要么都不加，必须保持一致)。