What causes reverse DNS failures from AT&T and how can they be resolved?

Email marketer from StackOverflow answers that a common cause is that the IP address being used to send email does not have a PTR record set up, or the PTR record does not match the hostname used in the HELO/EHLO greeting. Ensure your PTR record is correctly configured and matches your sending domain.

Email marketer from Email Geeks shares that they are seeing reverse DNS failures from ATT this morning.

Email marketer from EmailAdminForums shares that temporary reverse DNS problems with providers such as AT&T are often quickly resolved so advise is to monitor for 24 hours before trying to apply any fixes your end.

Email marketer from Reddit shares that reverse DNS failures from AT&T are often a waiting game. They suggest monitoring the situation and checking if AT&T's status page reports any known issues. Workarounds might include using a different sending IP or temporarily throttling email volume to AT&T domains.

Marketer from Email Geeks shares a command to check the MX records for att.net and suggests prioritizing IPs `.143` and `.144` if possible, or to wait for the fix.

Email marketer from SendGrid Support explains that if AT&T is experiencing rDNS issues, it could affect deliverability to their users. They recommend monitoring the situation, contacting AT&T support directly, and ensuring your sending reputation is high to mitigate potential impact.

Expert from Spam Resource, John Levine, responds to a question regarding mail delivery failures and the importance of reverse DNS. He explains the reason email servers will bounce if rDNS cannot be found. He shares that a large fraction of mail servers on residential IP addresses are blocked and they need to have rDNS set up to authenticate who they are.

Expert from Word to the Wise, Laura Atkins, discusses the importance of maintaining a good sending reputation and proper email authentication. She explains the importance of ensuring valid rDNS records point to the sending servers and that both forward and reverse DNS records match. She discusses the impact of DNS issues on corporate email delivery and the requirement for corporate senders to correctly setup their sending infrastructure.

Expert from Email Geeks responds that it is a widespread issue.

Expert from Email Geeks shares that they are seeing reverse DNS failures from ATT.

Expert from Email Geeks responds that many people are reporting the reverse DNS failures from ATT and it's not isolated to one person. They share that AT&T has been made aware of the issue, but an ETA for a fix is unknown.

Expert from Email Geeks shares that they are seeing reverse DNS failures from ATT.

Documentation from Digital Ocean explains that a reverse DNS record (rDNS), also known as a PTR record, resolves an IP address to a domain or hostname. Configuring rDNS for your server gives it a hostname that other servers can use to verify its identity. This can help your server gain trust and avoid being marked as spam.

Documentation from Google Admin Toolbox explains that rDNS lookups are a key element of identifying mail servers. Problems with rDNS records will cause issues when sending to any mail provider not just AT&T

Documentation from AT&T Support explains that reverse DNS failures can occur due to temporary outages or misconfigurations within AT&T's network. Resolution involves contacting AT&T support to report the issue and request a correction of the DNS records.

Documentation from RFC explains that the absence of a valid rDNS (PTR) record can cause email servers to reject the email due to anti-spam measures. It highlights the importance of correctly configured rDNS for mail server identification and reputation.

Documentation from MXToolbox explains that reverse DNS failures can stem from incorrect PTR records. To resolve, ensure your sending IP has a corresponding PTR record pointing back to your domain's hostname. They also recommend using their tools to diagnose and verify the PTR record configuration.