Playing around with Exim, Spamassassin, DKIM and SPF
I was playing around with my mail server today and decided to have a look at DKIM and SPF. Jump to the bottom for some useful links. You will have to be able to change TXT entries for your domain/subdomains to do any of this. Sending a mail to check-auth@verifier.port25.com will generate an auto-reply with the result of your mail servers settings. I also noticed that Exim wasn’t listening to the IPv6 interface and promptly fixed that, and have received my first mail via IPv6.
Some spamassassin scores for your local/user settings:
1 2 3 4 5 6 | score SPF_PASS -1.0 score SPF_FAIL 3.5 score SPF_SOFTFAIL 1.0 score SPF_HELO_PASS -1.1 score SPF_HELO_FAIL 3.5 score SPF_HELO_SOFTFAIL 1.0 |
SPF:
Syntax: http://www.openspf.org/SPF_Record_Syntax
Tools & Information: http://www.openspf.org/
Wizard: http://www.spfwizard.net/
DKIM:
Exim walkthrough: http://mikepultz.com/2010/02/using-dkim-in-exim/
Domain specific settings: http://www.debian-administration.org/users/lee/weblog/41
Tools: http://dkimcore.org/tools/
Wizard: https://www.port25.com/dkim-wizard/