Fastmail now supports Dynamic DNS for domains hosted with us.
It uses dyndns2, so ddclient and many home routers support it. There’s also a simpler one-line API for cron.
Dynamic DNS is a new opt-in record type. Its token can only update those records, not your regular A/AAAA, MX or DKIM records.
For some, not having Dynamic DNS blocked them from hosting their DNS with us.
Nothing changes unless you set it up.
https://www.fastmail.com/blog/keep-your-home-server-reachable-with-dynamic-dns/


