Quick answer: Working email DNS needs five pieces: MX records (where mail is delivered), SPF, DKIM and DMARC (proving your outgoing mail is genuine), and — if you send from your own server — a PTR record mapping your IP back to your mail hostname. Miss one and deliverability suffers.
Overview
Receiving mail depends only on MX. Getting your outgoing mail into inboxes depends on the authentication trio plus reverse DNS and IP reputation. This article wires them together; the per-record guides go deeper.
Before you start
- Decide where mail lives: a third-party provider (recommended for most) or your own server.
- Collect the provider's required records, or your own mail server's hostname and IP.
Step-by-step guide
- MX — point at your mail system (details):
example.com. MX 10 mail.example.com.- A record for the mail host (self-hosting):
mail→ server IP. - SPF / DKIM / DMARC — publish all three (combined guide).
- PTR (reverse DNS) — for a Cloud2Y server, set your IP's PTR to
mail.example.comvia the Client Area or a support ticket; it must match the name your server uses in SMTP HELO. - Test end-to-end: send to a Gmail address and inspect “Show original” — SPF, DKIM and DMARC should all say PASS.
Common issues
- Webmail works, custom domain does not: MX still points at the old provider or a stale record lingers.
- Mail lands in spam despite MX being right: almost always missing SPF/DKIM/DMARC or a generic PTR.
- MX to a CNAME: standards violation that some receivers punish — target an A-resolvable name.
- Autodiscovery missing: clients cannot auto-configure; add the CNAMEs your provider documents.
When to contact support
PTR records for Cloud2Y IPs are managed on our side — open a ticket with the desired hostname if you cannot set it in the Client Area. Also contact us if outbound port 25 appears blocked for your service.
Frequently asked questions
What DNS records does email need?
MX for inbound routing, SPF, DKIM and DMARC as TXT records for outbound authentication, and a PTR (reverse DNS) entry matching your mail server's hostname if you self-host.
How do I set a PTR record for my Cloud2Y IP?
Reverse DNS for Cloud2Y addresses is managed on our side: set it on the service page in the Client Area if the option is shown, or open a ticket with the desired hostname.
Mail arrives but my messages go to spam — why?
Inbound only proves MX works. Spam-foldering points at missing SPF/DKIM/DMARC, a generic PTR record, or poor IP reputation — publish the trio and verify with a Gmail test.
Related articles
- How to configure SPF, DKIM and DMARC
- How to configure MX records
- How to set reverse DNS / PTR record
- How to configure TXT records
Need a hand? Contact Cloud2Y support →
