CentOS 系统 Nginx 环境cd /usr/local/src
wget https://dl.eff.org/certbot-auto
chmod a+x certbot-auto
./certbot-auto --nginx（自动）
出现以下内容表示成功：
IMPORTANT NOTES:
- Congratulations! Your certificate and chain have been saved at:
/etc/letsencrypt/live/c.pensukeji.com/fullchain.pem
Your key file has been saved at:
/etc/letsencrypt/live/c.pensukeji.com/privkey.pem
Your cert will expire on 2018-10-16. To obtain a new or tweaked
version of this certificate in the future, simply run certbot-auto
again with the "certonly" option. To non-interactively renew all
of your certificates, run "certbot-auto renew" - Your account credentials have been saved in your Certbot
configuration directory at /etc/letsencrypt. You should make a
secure backup of this folder now. This configuration directory will
also contain certificates and private keys obtained by Certbot so
making regular backups of this folder is ideal. If you like Certbot, please consider supporting our work by:
Donating to ISRG / Let‘s Encrypt: ??https://letsencrypt.org/donate
Donating to EFF: ???????????????????https://eff.org/donate-le
./certbot-auto renew --dry-run（测试自动续订）
./certbot-auto renew（执行自动续订）
定时任务
为了做到自动化，我们要设置计划任务定时检查更新
编辑/etc/crontab增加一行规则
**12** root ./usr/local/src/certbot-auto renew
详细过程，手动过程及各个版本的安装方式可到以下官网自行查看
Certbot官网网址：https://certbot.eff.org/
使用 certbot 对网站免费加 https 协议
原文地址：http://blog.51cto.com/12384628/2151060