Interactive map showing the email providers of all ~2,100 Swiss municipalities, based on DNS analysis of MX and SPF records.

I’m in the process of taking back control of my email hosting situation and I needed a backup mx infrastructure to handle receiving mails if my primary mail server (hosted at home) is unavailable for any reason. Ideally it should be as simple as possible to avoid any configuration mistakes …

How to setup DNS records to ensure that domains that do not send email cannot be used for spoofing.