mail server setup

[Jason White]

Gregory Nowak <greg at gregn.net> wrote:
 
> Dkim: <https://en.wikipedia.org/wiki/Dkim>. In short, it authenticates
> e-mails sent from a given domain, with some caveats. I don't know
> either what dmark is as that would relate to the internet; a search of
> the web doesn't help.


It's spelled "DMARC". It specifies the SPF and DKIM policies for a domain and
allows recipients to send reports regarding messages that passed or failed SPF
and DKIM checks.
https://tools.ietf.org/html/rfc7489

Currently, I am experimenting with rspamd as a spam filtering solution. It was
reviewed favourably on Linux Weekly News last year, performs well and includes
a variety of checks (DMARC among them) on incoming messages. It also has a
Bayesian statistical classifier similar to the default classifier in crm114.

It's too early to report on its effectiveness in my installation.

I have also added SPF, DKIM and DMARC records to my domain. Outbound mail is
signed with opendkim.

I'm running Postfix as my mail transfer agent, but these tools support
Sendmail as well.

Setting up a server is easy; filtering spam is less so, unfortunately.

Various tutorials related to DKIM, SPF and DMARC have been published too.