Monthly Archives: November 2012

whois

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Here’s a tip for internet domain owners:

Make sure the contact information for your domain has more than one email address.  And make sure at least one of those email addresses is not in the domain itself.

If your email starts malfunctioning, you want people to be able to tell you about the problem … and if the only email addresses you list are in the actual domain, they won’t be able to contact you.

For example … if the mail server for example.com is having problem … and all the domain registration in the whois database shows ‘joe@example.com’, Joe won’t be able to be notified there is a problem.

The contact information is publicly accessible via the ‘whois’ databases.

Domain registrars that offer whois privacy capabilities should let you list more than one email address when they redirect the email address that they list in the whois look-ups.

For privacy sake, I like using a PO Box for the mailing address on all my domains.

Adding Envelope Sender in sendmail

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Fair warning: This post is pretty darn technical and is of little interest to people who don’t muck around with Linux and/or mail servers.

Recently I had a problem with someone on a midrange.com mailing list where they sent obvious spam.

The problem was, they were a subscriber to the list and had posted before … so the normal counter measures for that didn’t work (the first post for all subscribers are held until approved, to prevent people from subscribing, posting spam, and unsubscribing).

The puzzling thing about this was … the ‘from address’ on the message was not in the subscriber list.

Turns out that Mailman will accept message based on the FROM address of the message or the SENDER address (also known as the envelope-from).  The sender addressed is set by the sending mail server and is not normally in the body of the message.

After a bit of digging around, I figured out a way to add this information to the message headers so I can more easily diagnose the problem in the future.

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