Mail server DNS records - setup and configuration explained 

Thank you so much, it makes me happy to see it helps so many people 😁

@@christianlempa I second his comment. Thank you for your great explanation and awesome videos!

@@christianlempa Thank You Very Much

Thanks you so much! It really makes me happy to read such a comment :)

Haha, I would love to see a video like this pop up ;) Thank you!

Thanks! :)

Thank you so much :)

Thank you ;) Great it was helpful!

Thank you!

thank you! glad it helped you :)

Thank you mate

Freut mich sehr!

Thank you so much! :)

Glad it was helpful!

Glad it was helpful!

Thanks man ☺️

Thank you too!

Thank you so much 🤣👍

Thank you so much :)

Thanks 😆

Thank you 😊

thanks mate!

You're welcome!

Danke :)

Welcome 😊

Glad you think so!

Thank you so much! :)

Thank you! Cheers!

Sehr gerne ;)

Haha don't worry ;) thanks man

Thanks mate :)

Sehr gerne :) freut mich dass es geholfen hat

Thank you, man 😉! If you have only one IP address, you can only set 1 rDNS name. You could choose one domain as the main domain for the mail server and point all MX records of the other domains to that mail server DNS, that's how I do it in my setup. If these domains are for different customers, you could simply use your company domain as a mail server (that's how ISPs, Office365, etc. do it). Or get more IP addresses from your hoster.

Yea that's definately something you need! If you don't have a static IP address at home, that's going to be a challenge though.

You need to ask your ISP to create the PTR record for you, but in order to do that you need to get a static IP. And they probably won't do it for you because ISPs generally don't want people hosting mail servers on a residential connection. Although like TDL said hosting a mail server at home is probably not going to work. If you haven't run into this already, you'll probably find that your ISP blocks incoming and outgoing connections to port 25, which is the standard port that all mail servers use to talk to one another (and you can't change this, not even with a SRV record). Having a dynamic IP is its own big issue - even if you get the mail server working, you'll be chugging along and then one day it just breaks because your IP changed. If you do insist on hosting it at home though you can use services like dnsexit to relay incoming or outgoing mail for you to different ports. For example you can configure your mail server to send outgoing mail to a relay server on port 24, which may not be blocked, and the relay server will send the mail for you. Of course you'll probably have to pay for something like this if you do use it and if you're going to pay then why not shell out for hosting?

Yeah you need to setup them separately

Yes you can, you would still need to set up a mail server somewhere but once you do that you can configure your DNS records like in the video to point to that mail server

Digitalocean automatically configures a PTR based on the hostname you set in the droplet. So always set a valid FQDN as a droplet hostname and you should be fine. Also make sure you contact Digitalocean to open the port 25 to your account, by default it's blocked... took me 2 hours to find out :D

If your mail server is behind a router you probably need to forward the SMTP port 25 and the web ports 80, 443 and IMAP/POP if you need to connect mail clients.

You need to talk to your ISP or configure it on your router if possible

Hi, I would recommend checking with google. Maybe your IP reputation is bad. This can happen if it's not a static IP, but dynamic or due to previous abuse.

If you're running the mail server On-Prem you would need to ask your ISP.

Haven't heard about that, maybe just give your provider a chat

No, some mail servers might retry to send you the emails, but if that's longer than a few days... probably not. However, the Sender should have received an "undeliverable" response and might try to contact you again.

Well, if you configure it right, it shouldn't

Should be possible, all DNS records are standardized. But I don't have any experience with that with bind, sorry.

You can configure multiple email addresses and aliases in the web admin of mailcow, I hope that helps :)

Check if you've set the correct nameservers in Godaddy.

Yes that sounds about right. Dynamic IPs are reassigned, so your PTR record will be invalid when your IP is reassigned. I would also recommend not running a mail server at home because this is one of the many problems you'll face. If you haven't yet, you'll also find that your ISP blocks incoming and outgoing connections to port 25, so none of your emails will even make it to any other mail server and vice versa. The best thing to do is to just shell out for hosting and set up your mail server on a remote machine with a business class connection and no port restrictions (or port restrictions that can easily be lifted).

I'm working on that. I'm updating my cheat sheet on Github: github.com/xcad2k/cheat-sheets

Maybe your IP address was blacklisted from Microsofts servers. I would create a support ticket, and ask the guys if your IP is on a blacklist and how to remove it.

@@christianlempa yes please how i can send you the ip

Haha that's great, thank you! :)

You can host multiple domains very easily. You can create an MX for every domain which points to your FQDN of your Mailserver.

@@christianlempa thanks

Well not really, I'd need more details :) Why not come to our Discord and share your setup, maybe we're able to help you out there.