CentOS7.X生成免费SSL通配符证书

安装certbot

1. 安装certbot

   yum install epel-release -y
   yum install certbot -y

2. 生成证书(*.xxx.com为通配符域名)

   certbot certonly --manual --force-renewal --server https://acme-v02.api.letsencrypt.org/directory --preferred-challenges dns-01 -d "*.xxx.com,xxx.com"
   # 1.执行过程中输入邮箱
   # 2.执行过程中输入A同意
   # 3.执行过程中输入Y确认
   # 4.执行过程中输入Y确认
   # 5.执行过程中添加DNS的TXT解析记录,以阿里云DNS为例
      # 记录类型TXT
      # 主机记录_xxx-xxx.xxx.com
      # 解析线路默认
      # 记录值xxx
      # TTL 10分钟
   # 6.按下回车,提示成功！
   # 7.执行过程中添加DNS的TXT解析记录,以阿里云DNS为例
      # 记录类型TXT
      # 主机记录_xxx-xxx.xxx.com
      # 解析线路默认
      # 记录值xxx
      # TTL 10分钟
   # 8.按下回车,提示成功！

3. 按照成功后的提示，记下证书文件的路径，提示信息类似如下

   IMPORTANT NOTES:
    - Congratulations! Your certificate and chain have been saved at:
      /etc/letsencrypt/live/xxx.com/fullchain.pem
      Your key file has been saved at:
      /etc/letsencrypt/live/xxx.com/privkey.pem
      Your cert will expire on 2xxx-xx-xx. To obtain a new or tweaked
      version of this certificate in the future, simply run certbot
      again. To non-interactively renew *all* of your certificates, run
      "certbot renew"
    - 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
   
   # 生成的文件放在：
   /etc/letsencrypt/live/xxx.com/fullchain.pem
   /etc/letsencrypt/live/xxx.com/privkey.pem
   
   # 该证书有效期90天，90天后再重复本步骤，续期90天

4. 配置Web服务器并重载配置