We've returned to our normal routing process and all systems have rejoined routing groups. We're sorry for the inconvenience and support activity this caused.
Update 08/14/2023 14:47 PM 13 days
The systems impacted by this issue have been removed from the network and we've confirmed that messages that were in the queue have been scanned and delivered.
We have removed the network that caused this issue from active routing. Delivery times are not being impacted.
Details: The error command 5.7.1 was issued due to a permanent failure in the SPF framework that validates senders domains and their SPF DNS records. The issue was caused by an upstream DNS server taking too long to respond to certain requests. This issue (and the related one with admin.exchangedefender.com) were caused by an OTA update to our network switches which caused some systems not to bring up the appopriate network interfaces (leading to decreased performance leading to timeouts leading to failure leading to errors).
Update 08/14/2023 14:15 PM 13 days
We're having an issue with SPF/DKIM detection in Dallas and regrettably a number of messages have been rejected with error code 5.7.1 as the system could not resolve the SPF record.
The network has been removed from our routing while we investigate so you should not be seeing any further errors. We will update this NOC when we bring the systems back online but in the meantime the email is routing without issue.