How to resolve Gmail PTR record error when using Cloudflare?
Summary
What email marketers say13Marketer opinions
Email marketer from Webmaster World shares that email delivery issues with Gmail when using Cloudflare often stem from a mismatch between the sending IP (Cloudflare's IP) and the PTR record (which should point to your server's IP). To resolve this, either route email directly from your server (bypassing Cloudflare) or use a third-party email service that handles PTR records correctly.
Email marketer from Reddit explains that when using Cloudflare, the IP address used for sending email is likely Cloudflare's IP, not your server's. Google checks the PTR record of the sending IP. Because Cloudflare's IP doesn't have a PTR record pointing to your domain, Gmail rejects the email. The solution is to use an external SMTP service or ensure your server's IP is used for sending email and has a correct PTR record.
Email marketer from HostAdvice responds that reverse DNS (PTR) records map IP addresses to domain names. Email servers often use PTR records to verify the identity of sending servers. When using Cloudflare, email may appear to originate from Cloudflare's IP addresses, leading to authentication failures. Using a dedicated email sending service or bypassing Cloudflare for email traffic are common solutions.
Marketer from Email Geeks shares that SocketLabs offers 2,000 a month.
Marketer from Email Geeks explains that if you have to send directly, having the forward and reverse lookups match (Forward-Confirmed reverse DNS) is pretty much a requirement. Also says PTR records are set by the IP block owner, not Cloudflare, and DKIM is also pretty much required but won't let you not have proper reverse lookups.
Email marketer from DigitalOcean Community explains that to resolve PTR issues, you need to configure the PTR record at the IP address owner level (usually your hosting provider). If you're using Cloudflare for DNS but your server is hosted elsewhere, Cloudflare cannot manage the PTR record. You need to contact your hosting provider to set the PTR record to match your domain name.
Email marketer from Namecheap explains that PTR records are set at the server level (where your website is hosted), not at the domain level (where you manage your DNS records). So Namecheap cannot set it but your hosting provider can. When you use Cloudflare for name servers, your domain uses Cloudflare's IP addresses, and your hosting server's IP address becomes hidden, causing issues with email deliverability and PTR record verification.
Email marketer from ServerFault notes that Gmail's PTR record error can arise if the IP address sending emails from your server lacks a valid PTR record or if the hostname in the PTR record doesn't match the hostname used in your email headers. This is common when using Cloudflare due to IP address masking. The advice is to either use a dedicated mail server with proper PTR setup or relay emails through a third-party service.
Email marketer from Cloudflare Community recommends using a dedicated email sending service (like Mailgun or Sendgrid) when your website is behind Cloudflare. Cloudflare's primary function is web traffic management, not email delivery, and using a dedicated service ensures proper email authentication (SPF, DKIM, DMARC, and PTR records) which can prevent emails from being flagged as spam.
Email marketer from Stack Overflow suggests using a transactional email service like SendGrid, Mailgun, or Amazon SES to relay emails. These services handle the technical aspects of email deliverability, including PTR records, SPF, DKIM, and DMARC, which can resolve Gmail's PTR record error when using Cloudflare.
Marketer from Email Geeks shares that Postmark offers 100 emails a day to anyone as well, in case you need more than 5 recipients.
Marketer from Email Geeks suggests that if a web server needs the proxying that Cloudflare provides, then it should relay out through a dedicated SMTP service. If it doesn't need the proxying and you just like the Cloudflare interface, disable it. Then reiterates not to send directly from the web server.
Email marketer from cPanel Forum responds that the Gmail error indicates a mismatch between the IP address and its reverse DNS (PTR) record. When using Cloudflare, the email is likely being sent from a Cloudflare IP, which doesn't match your domain's PTR record. To fix this, either bypass Cloudflare for email traffic or use a dedicated SMTP service with a correctly configured PTR record.
What the experts say4Expert opinions
Expert from Word to the Wise highlights that a correct PTR record is crucial for establishing trust with receiving mail servers. It confirms that the IP address sending the email is authorized to send mail for that domain. Using a service like Cloudflare can interfere with this process if not configured correctly. So its key to implement forward-confirmed reverse DNS (FCrDNS), meaning your IP resolves to a domain name, and that domain name resolves back to the same IP address.
Expert from Spam Resource explains that one way to resolve PTR record issues when using Cloudflare is to utilize a dedicated third-party email sending service. These services typically manage their own PTR records and have established relationships with major email providers like Gmail, which can improve deliverability.
Expert from Word to the Wise says that when using Cloudflare, the Cloudflare IP addresses may obscure your server's true IP address. This can cause authentication failures because the PTR record of the sending IP won't match your domain. One possible approach is to ensure that your email is routed directly from your server (bypassing Cloudflare's proxy), or to use a reliable SMTP relay service to handle email sending and authentication.
Expert from Spam Resource indicates that when using Cloudflare, your email may be sent from Cloudflare's IP addresses, which may not have PTR records associated with your domain. To avoid issues, ensure that your email DNS records (MX, SPF, DKIM) are correctly configured, and consider using an email delivery service or bypassing Cloudflare for email traffic to maintain proper PTR record alignment.
What the documentation says5Technical articles
Documentation from Microsoft Learn recommends creating a PTR record that matches the IP address of your mail server and points to your domain name. It specifies that incorrect or missing records can result in delivery problems. This is particularly important when using third-party services like Cloudflare for website management, which might obscure the true source IP of your email server.
Documentation from MXToolbox explains that PTR records (Pointer Records) are used to map an IP address back to a domain name (reverse DNS lookup). A properly configured PTR record is essential for email deliverability, as it helps receiving mail servers verify that the sending server is legitimate. The documentation also provides tools to check if a PTR record is correctly set up.
Documentation from Google Workspace Admin Help explains that Gmail requires a valid PTR record for the sending IP address. The PTR record must resolve to a hostname, and that hostname must have a corresponding A record that resolves back to the sending IP address. This is to ensure that the sending server is legitimate and not a source of spam. If using Cloudflare, ensure email is not proxied through Cloudflare IPs, or use a dedicated email sending service.
Documentation from Cloudflare explains that when using Cloudflare, the actual IP address of the origin server is hidden. For email, it is essential to either bypass Cloudflare (configure DNS records to directly point to the origin server) or use a dedicated email delivery service that handles email authentication correctly, including SPF, DKIM, and PTR records.
Documentation from RFC 5321 details the importance of reverse DNS lookups (PTR records) for email server authentication and spam prevention. It emphasizes that a missing or incorrect PTR record can lead to email delivery issues, as it makes it difficult to verify the legitimacy of the sending server. This is particularly relevant when using services like Cloudflare that may mask the original sending IP address.