[not_your_vase]

I tried to set up a self hosted mail server just a few months ago, but I stumbled over 1 minor thing.

I have a residential connection of course. Thought contractually I have a dynamic IP, in practice it hasn't changed ever since I have been with them (which is now 7 or so years). I can host my own website from my home without a problem. Also, all the necessary ports are unblocked. So that's great.

I started to follow some tutorials, and it was working fine, I could send emails to certain places. But not everywhere. Most notably not to gmail. And that's when I started to learn about DMARC and other email security thingies. I started to set them up, and one of them required me to set up RDNS records.

When I contacted my ISP about that, the customer service folks had no idea what I was talking about. After a few rounds of back and forth, I gave up. (3 years ago I really thought that AI would solve such customer support issues by now. I was wrong.)

And I don't really know what else... I guess I would use some smtp relay services, though I haven't found one yet that would sell only smtp relay, without some other hosting bundle.

[pestatije]

why would you contact ur ISP to set RDNS records? u set them the same way as any other DNS records

[not_your_vase]

Ahh, I would have to dive into the details again to get the exact answer... But from what I can recall is for reverse DNS I need a PTR record also, and for a PTR record I need to know my IP's reverse zone (or setup one?), and that's where my ISP came into picture as the owner of the IP block, as they are the only ones who can do that.