Publishing your domain's email records does not configure the reverse DNS of the server sending your mail. That record belongs to the sending IP's address zone.
Who controls a PTR record?
The operator responsible for the IP address controls its reverse DNS or delegates that control.
A reverse DNS zone holds names associated with an address block. Your domain's DNS zone is a separate area of authority. Permission to edit example.com therefore does not grant permission to change a sending IP's PTR record.
A hosting provider may offer a control panel or accept a configuration request. A sending platform usually handles the reverse zone for the addresses it supplies. Use the operator responsible for the address, even when your domain's records are hosted elsewhere.
What must the forward and reverse lookups show?
The sending IP must resolve to a hostname that resolves back to the same IP. Gmail can temporarily limit or block mail when those lookups disagree.
Google's sender requirements require both directions. Publish the sending IPv4 address in an A record at the PTR hostname. For IPv6, publish an AAAA record.
If the PTR record names mail.example.com, that hostname must have an address record containing the sending IP. A hostname that no longer resolves fails this check. A hostname resolving only to another IP fails too.
RFC 1912 recommends matching reverse records for each address of a host with multiple IPs. Checking only one address can leave traffic from another without a valid reverse lookup.
Point your PTR record directly to the hostname holding the sending IP's address record to avoid an extra lookup. A CNAME alias adds this indirection, which RFC 1912 discourages.
Does Gmail require PTR records from low-volume senders?
Yes, Gmail requires matching forward and reverse DNS from every sender.
The requirement does not depend on entering the bulk-sender tier. A low-volume application sending password resets still needs a properly configured sending IP.
Google's Postmaster Tools dashboards include a bad-or-missing-PTR delivery error. If that error appears, investigate the sending IP's reverse lookup before changing unrelated domain authentication records.
An email server identifies itself with a HELO greeting containing its hostname. Match that greeting's hostname to the server's hostname and reverse DNS, as Spamhaus recommends. Misconfigured servers can have delivery problems even where receivers do not use Spamhaus lists.
What should you do for your sending setup?
Configure reverse DNS through the operator of your sending IP, or ask that operator to correct a mismatch.
| How you send | Who can configure the reverse record |
|---|---|
| A platform's shared sending IPs | The platform or its address provider |
| A platform's dedicated sending IP | The platform or its address provider |
| Your own mail server | Your hosting provider, or you if reverse-zone control is delegated |
A dedicated IP does not automatically give you control of its reverse zone. A managed service can still have a mismatch. Confirm the configuration when diagnosing a new address.
For platform sends, provide the failing IP and delivery error to support. For a server you manage, check both DNS directions and the greeting hostname. Blocklist checks address a separate possible cause of refusal.
In short
PTR records belong to the address zone.
The operator responsible for an IP address controls its reverse DNS or delegates that control.
Forward and reverse lookups must agree.
The sending IP must map to a hostname that resolves back to the same IP.
Gmail requires reverse DNS from every sender.
Matching forward and reverse DNS are baseline requirements, regardless of bulk volume.
The sending operator handles the repair.
Ask the platform or hosting provider responsible for the IP when you cannot edit its reverse zone.