Email DNS Records Explained
Four kinds of DNS records make your email work and keep it out of spam folders. For a domain on CDNShark DNS they're published and kept up to date for you. For a domain with DNS elsewhere, add them as shown in the DNS tab of the Email page.
| Record | Name | Value | What it does |
|---|---|---|---|
| MX | @ | Our mail servers, priority 10 each | Tells the world where to deliver mail for your domain |
| TXT (SPF) | @ | v=spf1 mx -all | Says only your MX servers may send mail for your domain |
| TXT (DKIM) | <selector>._domainkey | A public key (RSA and ed25519) | Lets receivers check each message was signed by us and not changed |
| TXT (DMARC) | _dmarc | v=DMARC1; p=quarantine; adkim=s; aspf=s; rua=mailto:postmaster@your-domain | Tells receivers to quarantine mail that fails SPF/DKIM, and where to send reports |
Tips
- Create
postmaster@your-domainas a mailbox or an alias. DMARC reports from other mail providers are sent there. - Only one SPF record is allowed per domain. If you send through another service too, merge its rule into ours rather than adding a second record. See Send Mail From Other Services With Your Domain.
- The
-allin SPF andp=quarantinein DMARC are strict on purpose: they stop others from forging your address. - DNS changes can take up to a few hours to be seen everywhere, depending on the record's TTL.
Reverse DNS (PTR) for our sending servers is handled by us; you don't need to set anything.