Emails/DNS
From wiki
MX
The most important DNS record, is the MX one. It is the one that allows other persons to find your server and send you emails
@ MX 10 smtp
- Name (@): This must point to the root of your domain
- Type (MX):
- Value (10 smtp): Indicate that the server smtp.example.org will handle the emails of your domain. The number 10 represent the priority. YOu can add other servers with increasing priority (10, 20, 30...).
SMTP
This record is used for two purposes:
- It is the one pointed by the MX record above. External server will send emails here.
- It is also the one that you will use in your email client to send emails from your machine to other persons.
smtp A 198.51.100.42
AAAA 2001:db8:57:12::1
- Name (smtp): This will be expanded to smtp.example.org
- Type (A/AAAA): A for IPV4 and AAAA for IPV6. Note that as the above MX record is pointing to this one, you cannot use a CNAME here.
- Value: The IP address of your server
IMAP
This record is used for Dovecot.
imap CNAME server
- Name (imap): This will be expanded to imap.example.org.
- Type (CNAME): A for IPV4 and AAAA for IPV6. Note that as the above MX record is pointing to this one, you cannot use a CNAME here.
- Value (server): The name of your server. You must have a corresponding server.example.org record with the IP address.
SPF
The SPF record is a spam fighting tool. It allows to tell other mail server who is allowed to send emails on your behalf.
@ TXT "v=spf1 mx -all"
- Name (@): This must point to the root of your domain.
- Type (TXT): The SPF record is of this TXT. You might might find some example using a SPF record, but this type of record is deprecated and should not be used.
- Value: The SPF record must follow a strict syntax. The example above allow the server pointed by the MX record to send emails and disallow all others. For more options, you can use a SPF record generator.
DKIM
See Exim/DKIM
DMARC
_dmarc TXT "v=DMARC1;p=none;rua=mailto:you@example.org"
This record is used to access Roundcube.
mail CNAME server
- Name (mail): This will be expanded to mail.example.org
- Type (CNAME): A for IPV4 and AAAA for IPV6. Note that as the above MX record is pointing to this one, you cannot use a CNAME here.
- Value (server): The name of your server. You must have a corresponding server.example.org record with the IP address.