Reverse DNS maps an IP address back to a hostname. It's important for mail delivery — many providers reject mail from IPs without a matching PTR record.
Setting a PTR
- Open your server and go to the IP addresses tab.
- Find the address you want and click Edit next to it.
- Enter the fully-qualified hostname (for example
mail.example.com) and save. To remove it, clear the field and save.
Reverse DNS is capability-gated: it's only editable when the server's provider supports it. If an address has no Edit option, or the tab notes that reverse DNS isn't available from the provider, PTR records can't be set for that server.
Make it match
Set a matching forward (A/AAAA) record for the same hostname so the forward and reverse lookups agree — mail servers check for this. Changes propagate within a few minutes, though downstream caches may take a little longer.