Reverse DNS (rDNS / PTR record) maps an IP address back to a hostname (for example: 203.0.113.10 → mail.example.com). It is especially important if you send email from your VPS — many mail systems check that your IP has valid reverse DNS.
For best deliverability, set up FCrDNS (forward-confirmed reverse DNS):
mail.example.com)Typical choice is mail.yourdomain.tld or vps.yourdomain.tld. The hostname must be a fully qualified domain name (FQDN).
Create an A record in your DNS zone:
mailReverse DNS is configured at the IP provider level. To set it for a GARMTECH VPS:
After PTR is set, you can verify from any Linux/macOS terminal:
dig -x 203.0.113.10 +short
And verify forward DNS:
dig mail.example.com +short