https://blog.wongcw.com/2018/10/12/%e3%80%8e%e6%95%99%e7%a8%8b%e3%80%8f%e4%bd%bf%e7%94%a8-mailcow-dockerized-%e6%90%ad%e5%bb%ba%e4%b8%80%e4%b8%aa%e6%bb%a1%e5%88%86%e7%9a%84%e8%87%aa%e6%9c%89%e9%82%ae%e7%ae%b1%e6%9c%8d%e5%8a%a1/
『教程』使用 mailcow: dockerized 搭建一个满分的自有邮箱服务