Why am I getting Google bounces due to PTR record issues, even though my setup seems compliant?
Summary
What email marketers say10Marketer opinions
Email marketer from Email Geeks shares Google documentation stating that the sending IP address must match the IP address of the hostname specified in the PTR record.
Email marketer from StackOverflow indicates that even with a PTR record, a mismatch between the hostname used in the HELO/EHLO greeting and the IP address can cause bounces. He suggests ensuring the hostname presented during the SMTP handshake resolves to the sending IP.
Email marketer from MailChannels Support explains that your email might be getting blocked or sent to spam because of IP reputation issues. The IP may have a bad reputation due to previous spamming activity, even if the PTR is set up correctly.
Email marketer from Reddit shares that a common issue is the PTR record not matching the sending IP. They recommend double-checking with your ISP or hosting provider to ensure the PTR record is correctly configured for your mail server's IP address. Even if other tests pass, Gmail can be strict about this.
Email marketer from Postmark shares that you should check if the domain used in your SMTP HELO command matches the domain in your PTR record and the domain you use to send mail. If they don't align, it can cause deliverability problems.
Email marketer from SendGrid explains that, if you have recently made changes to your DNS records, it may take some time for those changes to propagate across the internet. The PTR record changes might not have been fully updated, leading to Google still seeing outdated information and bouncing your emails.
Email marketer from Word to the Wise explains the importance of Forward Confirmed Reverse DNS (FCrDNS). FCrDNS is when the PTR record resolves to an A record that matches the original IP address. Lack of FCrDNS is a common issue causing email delivery problems.
Email marketer from EmailDeliverability.com shares that if you're on a shared IP, the PTR record might be correctly set up for the IP, but it could be generic and not specific to your domain. This can still trigger bounces. She recommends considering a dedicated IP for better control.
Email marketer from SparkPost mentions that some ISPs or email providers, like Google, have stringent security measures that require PTR records to be correctly configured for optimal email delivery. Even if your PTR record appears correct, stricter policies may trigger bounces.
Email marketer from Litmus suggests using tools to check your DNS health and specifically look for inconsistencies between your forward and reverse DNS records. Often, these tools can highlight discrepancies that you might miss with manual checks.
What the experts say3Expert opinions
Expert from Email Geeks explains that the issue is not the PTR record itself, but the hostname the IP points to resolving to incorrect IPs. Google might be enforcing new requirements from last October. The user needs to change the DNS record for o1178.service.musclefood.com to point to 149.72.183.96 and delete the existing record that points to 18.130.118.158, ensuring no other services are using the old hostname.
Expert from SpamResource suggests that problems with email delivery require methodical diagnosis, including checking common DNS issues. Although they don't directly answer the PTR problem, they emphasise you should start with common problems, and these are normally in the DNS settings.
Expert from Word to the Wise explains the importance of Forward Confirmed Reverse DNS (FCrDNS). FCrDNS is when the PTR record resolves to an A record that matches the original IP address. Lack of FCrDNS is a common issue causing email delivery problems.
What the documentation says4Technical articles
Documentation from Google Workspace Admin Help explains that the sending IP address must match the IP address of the hostname specified in the Pointer (PTR) record. This is a requirement for sending emails to Gmail and helps prevent your mail from being marked as spam.
Documentation from Microsoft Docs clarifies that a reverse DNS (rDNS) lookup, using the PTR record, resolves an IP address to a domain name. It emphasizes that the forward and reverse DNS records should match. If they don't, some mail servers, including Google, may reject the email.
Documentation from MXToolbox explains that while you may have a PTR record, it needs to be correctly associated with your domain. They suggest using their tools to verify if the reverse DNS lookup matches your sending domain and IP. Incorrectly configured records are a common cause for deliverability issues.
Documentation from RFC1912, a key document for DNS setup, reiterates the importance of matching forward and reverse DNS records. The document notes that misconfigurations in DNS are a common cause for email delivery problems.