DNS Records for Email Sending
What each record is, where it goes, and when Zyntro checks it.
Setting up a sending domain means publishing five DNS records. Two prove the domain is yours to use and are checked before setup can continue; three authorise sending and are checked before it can be activated.
Throughout, comms.example.com stands in for your sending domain and example.com for your registered domain. The hostname and value for every record are shown on screen with a copy button, and for DKIM and SPF the values are unique to your domain — always copy those from the screen.
The five records
| Record | Type | Hostname | Value | What it does |
|---|---|---|---|---|
| Inbound routing | MX | Your sending domain, e.g. comms.example.com | inbound.postmarkapp.com (priority 10) | Routes mail addressed to your sending domain into Zyntro, so replies reach the platform. |
| Return path | CNAME | Your return path domain, e.g. inbound.comms.example.com | pm.mtasv.net | Collects bounce reports, so Zyntro knows which addresses failed and why. |
| DKIM | TXT | Unique to your domain — copy from the screen | Unique to your domain — copy from the screen | Signs your outgoing mail so recipients can confirm it was not altered or forged. |
| SPF | TXT | Your sending domain, e.g. comms.example.com | Copy from the screen; includes spf.mtasv.net | Lists which services may send mail for your domain. |
| DMARC | TXT | _dmarc on your registered domain, e.g. _dmarc.example.com | Your own policy, e.g. v=DMARC1; p=none; | Tells inbox providers what to do with mail that fails the SPF and DKIM checks. |
Warning: The MX record goes on the sending domain, and it redirects mail for that domain to Zyntro. Never publish it on a domain that already receives your email.
Which stage each record gates
MX
— Checked against live DNS in the first half of setup. Continue stays locked until it is found.
Return path CNAME
— Checked alongside the MX record in the first half of setup.
DKIM
— Issued after Continue, then checked in the second half. Also needs acceptance by the delivery service.
SPF
— Issued after Continue. Also needs acceptance by the delivery service.
DMARC
— Your own policy. Zyntro verifies it against live DNS; the delivery service is not involved.
What the dashboard states mean
Published in DNS
— A live DNS lookup found the record with the expected value. Your side of the work is done.
Accepted for sending
— The delivery service has checked the record and accepted it. This is the state that allows mail to go out, and it applies to DKIM, SPF and Return Path.
Single status
— These two are verified by Zyntro against live DNS only. The delivery service does not track either, so they show one status rather than two.
Tip: DKIM keys can be rotated. If DKIM stops verifying later, select Verify on the DKIM card: Zyntro re-reads the current record first, so the card updates to show the value you now need to publish.
