linux 的useradd 命令的p选项    
 
         错误用法: #useradd   gaojian   -p  gaojian
                     # 其实 -p 后面应该跟着的是 加密过的口令比如: 
                     #useradd tomjack
                     #passwd tomjack 输入口令明文:tomjack
                     查看 /etc/shadow文件: 
                     cat /etc/shadow | grep tomjack 
                     tomjack: $1$FHH178od$RxN/hIJBq1vWIF6GeRX9x1:15771:0:99999:7:::
                     把 第一个冒号和第二个冒号中间的部分拷贝出来用在useradd 的-p 选项上: 
                     #useradd  gaojian -p  $1$FHH178od$RxN/hIJBq1vWIF6GeRX9x1:15771
                     # 然后,重新启动,用 gaojian用户登录输入口令  tomjack ,可以登录成功 
05-11 13:36