安装依赖

yum install gcc gcc-c++ make 
yum install pam-devel make gcc-c++ wget

下载

wget https://google-authenticator.googlecode.com/files/libpam-google-authenticator-1.0-source.tar.bz2
tar jxvf libpam-google-authenticator-1.0-source.tar.bz2 

安装pam模块

cd libpam-google-authenticator-1.0 
make
make install

生成公钥

google-authenticator #生成公钥

启用Google验证模块

vim /etc/pam.d/sshd 
---------------------
auth       required pam_google_authenticator.so   #加载第一验证模块之前
---------------------

vim /etc/ssh/sshd_config 
---------------------
ChallengeResponseAuthentication yes # 修改
---------------------

service sshd restart #重启后切勿直接关闭终端

证书验证信息 && 万能秘钥

cat ~/.google_authenticator

CJEWH6THAJH5FUKI
" RESETTING_TIME_SKEW 47822956-958 47823967-958 47823452-959
" RATE_LIMIT 3 30 1439976483 1439976496
" DISALLOW_REUSE 47959316
" TOTP_AUTH
52449723
11133056
68918952
53756951
95063501