Web Programming, Linux System Administation, and Entrepreneurship in Athens Georgia

Check DomainKeys, DKIM, SPF valiadity, and SpamAssassin score in one place

I spent the whole day today stepping through DomainKeys, DKIM, and SPF for a customer to make sure that they were all set up and working properly. I found a couple of the existing tools available on the Internet didn’t test them properly and didn’t give enough explanation when they failed.

So, I went about creating some of my own tests using a bunch of Perl modules. I finally fixed a couple issues that I think were causing problems for this customer. Gmail and Yahoo are now delivering the messages anyway. Hotmail is still a mystery (no surprise since its from Microsoft). Their troubleshooting website is full of talk about how great their service is, but there is a huge lack of anything technical on the site.

Anyway, I made all of these nifty testers and figured that others might like to use them. So I created a way for others to send mail to it, and a web interface that you can view all of them results. I’ve added it as a link to the top of my website.

8 Comments

  1. Adrian

    Here is a good tool regarding to this post https://www.myiptest.com/staticpages/index.php/DomainKeys-DKIM-SPF-Validator-test

  2. Randy Owens

    Just a little suggestion for the SpamAssassin setup you use for checking on that page. It might be a good idea to turn off the auto(white|black)listing on it, so people aren’t getting hit with modifiers because they’re already sent off a few tests, like right now I’m getting “-1.3 AWL AWL: From: address is in the auto white-list”.

  3. Brandon

    @Randy,

    Great idea, thanks. That has been implemented now. I also found this post that describes how the auto-whitelist works

    The Problem With Spamassassin’s AutoWhitelist Feature

  4. OmegaSharp

    I sent an email as [email protected] via relay smtp.com. Your tool checks myhostspf.smtp.com for SPF records. Is this the correct way? Or shall I ask smtp.com to add such a SPF record?

  5. Brandon

    @OmegaSharp,

    I’m not sure I follow what is going on. If you are sending a message with an envelope sender of ‘[email protected]’, then you should have an SPF record for myhost.com that specifies that smtp.com is permitted to send mail from your domain name.

  6. Adam

    Brandon,

    Just wanted to say THANK YOU for this great tool! I’m a DKIM noob and it helped me debug my problem.

  7. Christina

    Hi, great post, just used this to check my DKIM and SPF. Love the idea that you don’t have to keep resending the message.

    However I’ve noticed that the SPF test sometimes returns “Result: PermError (Included domain ‘_spf.google.com’ has no applicable sender policy)”, and other times returns “Result: Pass (Mechanism ‘include:_spf.google.com’ matched)”? (on the same email, no DNS changes, with include:_spf.google.com in the SPF record). Is that an issue with the test, or an issue with Google’s servers?

    thanks,
    Christina

  8. Zlawa

    Can you release your implementation of this “email tester”?

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