Notes on what to check and what to setup for email and the DNS used by email.
DNS Settings
In these examples, I will use domain.com as the primary domain
| DNS Entry | Record Type | Set to |
|---|---|---|
| mail.domain.com | A | IPv4 address of mail server. This must be an A record not a CNAME record |
| mail.domain.com | AAAA | IPv6 address of mail server. This must be an AAAA record and not a CNAME record |
| domain.com | MX | host name of your mail server. eg mail.domain.com this should also be the reverse dns entry for the mail host. |
| autodiscover.domain.com | CNAME | mail.domain.com This is for your client email program to be able to autoconfigure itself |
| _autodiscover._tcp.domain.com | SRV | mail.domain.com port x (whatever your your server uses) |
| autoconfig.domain.com | CNAME | mail.domain.com |
| domain.com | TXT | your SPF record. Perform a web search for generate SPF record for more details |
| _dmarc.domain.com | TXT | your DMARC record. Perform a web search for generate DMARC record for more details |
| dkim._domainkey.domain.com | TXT | your DKIM record. Perform a web search for generate DKIM record for more details. Make SURE your email server's DKIM Selector matches the “dkim” prefix portion as in the example. |
Many of these settings are essential if you want the big mail servers to be satisfied your server is legitimate. Add as many of them as your mail server supports.
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