Hello my friend! Question about digital ocean.

Questions ArchiveCategory: Digital MarketingHello my friend! Question about digital ocean.
Siarhei asked 1 week ago

I have 1 droplet with 2 domains (2 sites). But if i want to send emails from both domains,  i need PTR record (rdns) to this sites. In digitalocean IP/ Droplet can only have a single PTR record, and i cant to make ptr records for my sites (hostnames). So mails have 8/10 on mail-tester. So the only way – 2 droplets for 2 sites?  And we can use 1 droplet only for multi subdomains, not for sites? 
Ps. Thank you very much for your courses!