I am lost in DNS and rDNS (PTR) record setting for the following scenario:
I have my main website example.com
running in Digital Ocean at IP 192.0.2.4
In Digital Ocean control panel I have the following records:
imap CNAME mail.example.com.
smtp CNAME mail.example.com.
example.com. MX mail.example.com.
mail A 192.0.2.8
I have my mail server at 192.0.2.8
hosted in different server (say Linode).
Due to missing rDNS (PTR) record system generated mail are not delivered correctly.
From Digital Ocean docs I have found that Digital Ocean configures PTR based on host name so I renamed my droplets to example.com
and changed hostname as well, so that it will create PTR records for me.
I don't have any clue what to do next as I am new to DNS stuff.
What am I missing here and how should I configure mail for this scenario so that there is no any problem regarding mail delivery and spamming issues?