Below you can find a list of **recommended DNS records**. While some are mandatory for a mail server (A, MX), others are recommended to build a good reputation score (TXT/SPF) or used for auto-configuration of mail clients (SRV).
["How to eliminate spam and protect your name with DMARC"](https://www.skelleton.net/2015/03/21/how-to-eliminate-spam-and-protect-your-name-with-dmarc/)
Make sure that the PTR record of your IP matches the FQDN of your mailcow host: `${MAILCOW_HOSTNAME}` [^1]. This record is usually set at the provider you leased the IP (server) from.
This example shows you a set of records for one domain managed by mailcow. Each domain that is added to mailcow needs at least this set or records to function correctly.
In the example DNS zone file snippet below, a simple **SPF** TXT record is used to only allow THIS server (the MX) to send mail for your domain. Every other server is disallowed but able to ("`~all`"). Please refer to [SPF Project](http://www.openspf.org) for further reading.
It is highly recommended to create a **DKIM** TXT record in your mailcow UI and set the corresponding TXT record in your DNS records. Please refer to [OpenDKIM](http://www.opendkim.org) for further reading.
The last step in protecting yourself and others is the implementation of a **DMARC** TXT record, for example by using the [DMARC Assistant](http://www.kitterman.com/dmarc/assistant.html) ([check](https://dmarcian.com/dmarc-inspector/google.com)).
```
_dmarc IN TXT "v=DMARC1; p=reject; rua=mailto:mailauth-reports@example.org"
```
## The advanced DNS configuration
**SRV** records specify the server(s) for a specific protocol on your domain. If you want to explicitly announce a service as not provided, give "." as the target address (instead of "mail.example.tld."). Please refer to [RFC 2782](https://tools.ietf.org/html/rfc2782).
```
_imap._tcp IN SRV 0 1 143 mail.example.org.
_imaps._tcp IN SRV 0 1 993 mail.example.org.
_pop3._tcp IN SRV 0 1 110 mail.example.org.
_pop3s._tcp IN SRV 0 1 995 mail.example.org.
_submission._tcp IN SRV 0 1 587 mail.example.org.
_autoconfig._tcp IN SRV 0 1 443 autoconfig.example.org.
_autodiscover._tcp IN SRV 0 1 443 autodiscover.example.org.
If you are interested in statistics, you can additionally register with the [Postmaster Tool](https://gmail.com/postmaster) by Google and supply a **google-site-verification** TXT record, which will give you details about spam-classified mails by your domain. This is clearly optional.
[^1]: A **Fully Qualified Domain Name** (**FQDN**) is the complete (absolute) domain name for a specific computer or host, on the Internet. The FQDN consists of at least three parts divided by a dot: the hostname (myhost), the domain name (mydomain) and the top level domain in short **tld** (com). In the example of `mx.mailcow.email` the hostname would be `mx`, the domain name 'mailcow' and the tld `email`.
