My mx record for example.com points to mail.example.com I have only set an AAAA record for mail.example.com, but no A record. I don't want to expose my IPv4, only the IPv6.
I can receive e-mail from a Gmail account, but when I run tests with online "send anonymous email" tools, the mails don't show up (but the same tools do work with my Gmail account).
When I use mxtoolbox, I see the correct IPv6 as well as a {No A Record} message.
Is it recommended to have an A-record set up, or should having only an AAAA-record work fine as well? What else could be the problem?