TLS-RPT record check
Checks whether TLS failures reaching your mail servers are reported to anyone, the feedback you need before enforcing MTA-STS.
Judged against RFC 8460 section 3
Symptoms
Silence. Mail that fails on TLS is retried and eventually returned to the sender, and the sender is the one who sees it. You find out when a customer mentions that their reply bounced. Without TLS-RPT there is no channel through which that reaches you.
Diagnosis
TLS-RPT is a single TXT record at _smtp._tls.yourdomain.com containing a version and a destination. Receiving providers batch up what happened when they connected to your servers and send you a daily summary.
The version string is v=TLSRPTv1 and it is case-sensitive. The destination is either a mailto: address or an https: endpoint. Anything else is discarded, and because nothing depends on this record working, nothing tells you.
Cure
- Publish
v=TLSRPTv1; rua=mailto:tlsrpt@yourdomain.comat_smtp._tls. - Point it at a mailbox someone actually reads, or a service that parses the JSON for you.
- Watch it for two weeks before moving MTA-STS from testing to enforce.
Questions people actually ask
What does TLS-RPT actually report?
Daily summaries from receiving providers about TLS connections to your mail servers: how many succeeded, how many failed, and why. It is the only external view you get of encryption problems in transit.
Do I need TLS-RPT if I have MTA-STS?
You need it more. MTA-STS in enforce mode makes senders refuse to deliver when TLS fails, TLS-RPT is how you find out that is happening, ideally before you turn enforcement on.
Where should the reports go?
A mailbox someone reads, or a reporting service. They arrive as JSON attachments, so a shared alias that nobody opens is the same as not having them.
Does TLS-RPT slow anything down or leak information?
No. It adds one DNS record and asks receivers to send you a daily summary. It contains aggregate connection data about your own servers.
Related tests
Every fix on this site is yours to implement. If you would rather someone did it, I take this work directly.