Why would my IP be on a Spamhaus blacklist due to a generic RDNS?

Email marketer from ServerFault shares that the rDNS record (reverse DNS) should resolve to the same hostname as the A record, which means the IP address and host name should match. If the hostname does not resolve to the same IP address, it could be flagged as spam.

Email marketer from cPanel Forums explains that using a generic RDNS (like one assigned by your ISP) can lead to deliverability problems. A proper, domain-specific RDNS is seen as a sign of a legitimate mail server.

Email marketer from Mailhardener.com shares that having a dynamic RDNS can negatively impact your email deliverability. ISPs and email providers often view these as suspicious because they are commonly associated with compromised or spam-sending machines. A static, properly configured RDNS is essential for establishing trust.

Email marketer from MXToolbox shares that a generic or missing reverse DNS (rDNS) record can indicate that an IP address is being used for spamming activities. They explain that setting up a proper rDNS record that matches the hostname of your mail server is crucial for email deliverability.

Email marketer from Reddit explains that dynamic IP addresses usually have generic RDNS records assigned by the ISP. Mail servers often distrust these because they are frequently used for sending unsolicited emails, leading to blacklisting.

Expert from Email Geeks shares that it’s a false positive, which spamhaus will fix, but suggests moving to something a bit less convoluted.

Expert from Spam Resource explains that the rDNS helps identify the source of an email and impacts your sending reputation. Generic or missing rDNS records can negatively impact your email deliverability and may contribute to blacklisting because they don't clearly identify your organization or infrastructure.

Expert from Email Geeks explains that the hostname is matching a “looks like generic” pattern and automation might see it as generic.

Expert from Word to the Wise explains that blocklisting can occur due to various factors, including IP reputation issues associated with generic RDNS. These issues can arise from spam traps, complaints, or evidence of spam-like activity.

Documentation from Hetzner.com explains that a missing or generic rDNS record is often used by spammers, so many mail servers reject emails from servers that don't have a matching rDNS record.

Documentation from Microsoft.com explains that using static IP addresses with a valid reverse DNS entry (PTR record) that matches the domain name is crucial for sending email. Dynamic IP addresses are often associated with spammers and may be blocked.

Documentation from Spamhaus.org explains that dynamic or generic RDNS listings often indicate that the IP address is being used by a home user or a small business with a dynamic IP address. These IP addresses are often used by spammers, so they are blacklisted.