Does rotating DKIM keys improve email deliverability and how should DKIM keys be rotated?

The consensus is that rotating DKIM keys is primarily a security measure that indirectly benefits email deliverability. It's crucial for preventing deliverability issues stemming from compromised keys, mitigating the risk of spoofing and phishing, and maintaining a positive sender reputation. While not directly boosting deliverability scores, a failure to rotate keys poses a substantial security risk. The recommended process involves generating a new key pair, updating DNS records (often including a new selector), testing the new key, transitioning mail flow to the new key, and eventually removing the old key. Different ESPs may have different methods for managing key rotation, and setting up multiple selectors from the start is beneficial. Regularly reminding yourself to change the key is important for continued security.

Rotating DKIM keys is primarily a security measure that indirectly benefits email deliverability. While not directly boosting deliverability scores, it prevents deliverability issues stemming from compromised keys, protects against spoofing and phishing attacks, and contributes to a positive sender reputation. The process involves generating a new key pair, updating DNS records (often with a new selector), testing the new key, switching mail flow, and eventually removing the old key. ESPs may handle rotation differently, some requiring customers to add new DNS records, while others use methods like CNAME ping-pong or maintain multiple selectors.

Experts generally agree that DKIM key rotation is crucial for email security, primarily to prevent deliverability issues that arise from compromised keys. While it may not directly boost deliverability, failing to rotate keys poses a significant security risk. Key rotation involves publishing a new key with a new selector, signing emails with the new key, and eventually removing the old key from DNS. Having multiple keys and a rotation strategy is recommended. CNAME ping-pong is a common method used by ESPs.

Documentation emphasizes that DKIM key rotation is a security best practice, primarily aimed at mitigating the risk of key compromise. While it doesn't directly improve deliverability, it prevents deliverability issues caused by compromised keys. The process involves generating a new key pair, updating DNS records, and gradually switching to the new key. DKIM uses selectors to facilitate key rotation, allowing senders to transition to a new key without invalidating old signatures by publishing multiple keys under different selectors.