Networking

Setting reverse DNS (PTR records)

Point your IPs back to your hostnames — essential for mail servers — and verify it.

3 min readReviewed 25 September 2026

Set a PTR record

On your server’s page in the client area, open Network → Reverse DNS, pick the address and enter the hostname, for example mail.example.org. It works for every IPv4 and IPv6 address assigned to you.

Match forward and reverse

Mail providers check that the reverse name points back to the same IP (forward-confirmed reverse DNS). Create the matching A or AAAA record at your DNS provider first, then set the PTR.

Verify

$ dig -x 203.0.113.10 +short
mail.example.org.
$ dig +short mail.example.org
203.0.113.10

Changes are usually visible within minutes, subject to the TTL of the previous record.

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