谷歌上google authenticator二次验证

参考:

GA安装:

https://www.cnblogs.com/hanyifeng/p/kevin4real.html

https://shenyu.me/2016/09/05/centos-google-authenticator.html

https://www.howtoing.com/secure-ssh-with-google-authenticator-on-centos-7

原理:

https://en.wikipedia.org/wiki/Google_Authenticator

原文地址：https://www.cnblogs.com/hongfeng2019/p/11596042.html