A short while ago, I updated blueprintq.com to go through a CDN. Today, I noticed that I was not receiving email; although, I was able to continue sending.
CDNs inject themselves by updating the zone file’s “A” domain record. Evidently, CDNs can also update other records. Sure enough, that’s what happened here. This is what I had to do:
- Delete the “CNAME” mail records – it was an alias of blueprintq.com.
- Add an “A” mail record to point to my mail server IP.
That did the trick. In fact, within five minutes after doing this, I received a dozen emails that must have been sitting in a queue somewhere – this would also explain why senders were not receiving bounceback emails.