NetworkingTutorial· Updated 30 May 2026

Configuring reverse DNS (PTR records)

Set a PTR record for your IP address so mail servers and logs show your hostname.

Reverse DNS maps an IP address back to a hostname. It is important for mail delivery — many providers reject mail from IPs without a matching PTR.

Setting a PTR 1. Open the IP Addresses section under your subnet. 2. Click the address you want to edit. 3. Enter the fully-qualified hostname (for example mail.example.com) in the PTR field and save.

Changes propagate within a few minutes on our authoritative servers, though downstream caches may take longer. Make sure a matching forward (A/AAAA) record exists for the hostname as well.

Knowledge Base

Configuring reverse DNS (PTR records)

Setting a PTR 1. Open the IP Addresses section under your subnet. 2. Click the address you want to edit. 3. Enter the fully-qualified hostname (for example mail.example.com) in the PTR field and save.

Knowledge Base

Configuring reverse DNS (PTR records)

Setting a PTR 1. Open the IP Addresses section under your subnet. 2. Click the address you want to edit. 3. Enter the fully-qualified hostname (for example mail.example.com) in the PTR field and save.