Summary
Gmail PTR record errors when using Cloudflare arise because Cloudflare's IP addresses are used for sending email, but these IPs lack PTR records matching your domain. This obscures your server's true IP and leads to authentication failures. Solutions involve using a dedicated SMTP service (like SendGrid, Mailgun, or Amazon SES) to handle authentication and PTR records, or bypassing Cloudflare for email traffic. Ensure forward and reverse DNS lookups match, configure PTR records at the IP block owner level (hosting provider), and properly configure email DNS records (MX, SPF, DKIM). Cloudflare's primary function is web traffic management, not email delivery. Proper forward-confirmed reverse DNS (FCrDNS) implementation is vital for trust.
Key findings
- IP Address Mismatch: Gmail PTR errors occur because Cloudflare's IP address (used for sending email) does not have a matching PTR record for your domain.
- Cloudflare's Proxy: Cloudflare's proxy obscures the actual IP address of your mail server, causing authentication and deliverability problems.
- PTR Record Configuration: PTR records are configured at the server level (hosting provider) and not within Cloudflare DNS settings.
- Forward-Confirmed Reverse DNS: Implementing forward-confirmed reverse DNS (FCrDNS) is essential for establishing trust with receiving mail servers.
Key considerations
- Dedicated SMTP Service: Use a dedicated SMTP service to handle email authentication, as these services manage their own PTR records and maintain relationships with major email providers.
- Bypassing Cloudflare: Consider routing email directly from your server (bypassing Cloudflare's proxy) to ensure proper PTR record alignment.
- DNS Record Configuration: Verify and properly configure email DNS records (MX, SPF, DKIM) to improve email deliverability and reduce the likelihood of being marked as spam.
- Contact Hosting Provider: Contact your hosting provider to set the PTR record to match your domain name, ensuring accurate reverse DNS resolution.
- Transactional email services: Transactional email services like SendGrid, Mailgun, or Amazon SES handle the technical aspects of email deliverability, including PTR records, SPF, DKIM, and DMARC.
What email marketers say
13 marketer opinions
When using Cloudflare, Gmail PTR record errors arise because Cloudflare's IP address is used for sending email, but its PTR record doesn't match your domain. Solutions involve using a dedicated SMTP service (like SendGrid, Mailgun, or Amazon SES) to handle email authentication and PTR records, or bypassing Cloudflare for email traffic. Ensure forward and reverse DNS lookups match, configure PTR records at the IP block owner level (hosting provider), and properly configure email DNS records (MX, SPF, DKIM). Cloudflare's primary function is web traffic management, not email delivery.
Key opinions
- PTR Mismatch: Gmail PTR errors with Cloudflare stem from a mismatch: Cloudflare's IP sends the email, but its PTR record doesn't match your domain.
- Cloudflare Proxying: Cloudflare hides your server's IP address, causing PTR record verification failures and deliverability issues.
- SMTP Service Required: A reliable solution is using a dedicated SMTP service, which manages its own PTR records and has established relationships with email providers.
- Hosting Provider Control: PTR records are configured at the IP block owner (hosting provider) level, not at the domain level (Cloudflare).
Key considerations
- Forward-Confirmed Reverse DNS: Having forward and reverse DNS lookups match (Forward-Confirmed reverse DNS) is crucial for email authentication.
- Bypassing Cloudflare: If possible, bypass Cloudflare for email traffic to ensure proper PTR record alignment and avoid deliverability issues.
- Proper DNS Configuration: Ensure correct setup of email DNS records (MX, SPF, DKIM) to improve email deliverability.
- Email vs. Web Traffic: Cloudflare is primarily for web traffic management; email requires specific handling for authentication and deliverability.
- Transactional email services: Transactional email services like SendGrid, Mailgun, or Amazon SES handle the technical aspects of email deliverability, including PTR records, SPF, DKIM, and DMARC.
Marketer view
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.
30 Jul 2021 - Webmaster World
Marketer view
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.
28 Jan 2025 - Reddit
What the experts say
4 expert opinions
When using Cloudflare, Gmail PTR record errors arise because Cloudflare's IP addresses are used, which may not have PTR records associated with your domain, obscuring your server's true IP. A correct PTR record is crucial for establishing trust with receiving mail servers. Solutions include utilizing dedicated third-party email sending services or routing email directly from your server (bypassing Cloudflare) to maintain proper PTR record alignment and ensure correct DNS configuration, implementing forward-confirmed reverse DNS (FCrDNS).
Key opinions
- Cloudflare Obscures IP: Cloudflare's IP addresses obscure your server's true IP, leading to authentication failures.
- PTR Record Importance: A correct PTR record is crucial for establishing trust and verifying the legitimacy of the sending server.
- Third-Party Email Services: Dedicated third-party email sending services manage their own PTR records and improve deliverability.
- Alignment with Domain: Ensure PTR records are aligned with your domain to prevent issues with email delivery.
Key considerations
- Bypassing Cloudflare: Consider routing email directly from your server, bypassing Cloudflare's proxy, to avoid PTR-related issues.
- DNS Configuration: Ensure email DNS records (MX, SPF, DKIM) are correctly configured for proper PTR record alignment.
- SMTP Relay Service: Use a reliable SMTP relay service to handle email sending and authentication, particularly when Cloudflare is in use.
- Forward-Confirmed Reverse DNS: Implement forward-confirmed reverse DNS (FCrDNS) for proper IP and domain name resolution.
Expert view
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.
12 Aug 2022 - Word to the Wise
Expert view
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.
11 Jul 2023 - Spam Resource
What the documentation says
5 technical articles
Gmail requires a valid PTR record for the sending IP, which must resolve to a hostname with a corresponding A record back to the IP. Missing or incorrect PTR records lead to delivery issues by hindering server legitimacy verification. Cloudflare hides the origin server's IP, necessitating bypassing Cloudflare or using a dedicated email delivery service to manage authentication records like SPF, DKIM, and PTR correctly.
Key findings
- PTR Record Requirement: Gmail requires valid PTR records for sending IPs to ensure server legitimacy and prevent spam.
- Reverse DNS Lookup: PTR records map IP addresses to domain names and are crucial for reverse DNS lookups.
- Cloudflare IP Obscurity: Cloudflare hides the origin server's IP, leading to PTR verification failures.
- Delivery Issues: Missing or incorrect PTR records result in email delivery problems.
Key considerations
- Dedicated Email Service: Use a dedicated email delivery service to handle authentication (SPF, DKIM, PTR) correctly.
- Bypass Cloudflare for Email: Configure DNS records to bypass Cloudflare and point directly to the origin server for email.
- Correct PTR Configuration: Ensure the PTR record matches the IP address of your mail server and points to your domain name.
- Verify PTR Setup: Use tools to check if the PTR record is correctly set up to avoid deliverability issues.
Technical article
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.
18 Apr 2023 - Microsoft Learn
Technical article
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.
13 Oct 2023 - MXToolbox
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