I have a dedicated server (Ubuntu 18.04 with virtualmin & webmin) which is hosting 7 WordPress sites on it. I have set up MX, DMARC, SPF and DKIM records for each one of them but dns tests online kept mentioning that I need to set up PTR records for reverse DNS too if I want to send/receive emails. (The other records passed successfully).
On googling about PTR records, I understood that I need to request my host to provide me with an ipv6 address which he did and gave me a link to set it up.
The link took me to a page with a single input field, a submit button and a one-line explanation that says:
Edit reverse DNS entry for XXXX:feXX:XXX:XaX::fXe:fXXd
What exactly should I add and submit here? The reverse IP address of my server followed by
.in-addr.arpa or something else? And what should I add in my domain registrar's record after?