This article currently is just a preholder to keep info to set up the mox server again and resolve all the DNS related issues.
DNS
First of all you will obviously need an A DNS record to address your server.
A: (somesubdomain.)mysite.com -> 1.2.3.4
And maybe you will need the AAA DNS record.
Then you will need the MX dns record, something like that:
MX: (somesubdomain.)mysite.com
Where the somesubdomain stands for any subdomain you want, by high chance it will be something like "mail" so the final domain would look like "mail.mysite.com" in this case.
DMARC
TXT: _dmarc(.somesubdomain) = v=DMARC1; p=reject
SPF
TXT: (.suomesubdomain) = v=spf1 a mx include:_spf.your.hosting.com ip4:1.2.3.4 ~all
DKIM
TXT: mail._domain_key(.somesubdomain) = v=DKIM1;t=s;p=HereWillBeAVeryLongPublicKey