Posts tagged: EMAIL

SPF-enabled spam domains

Among the many anti-spam measures on my mail server – which help me reject 5000 spam attempts per day – is SPF. SPF allows domain name owners to specify which mail servers are allowed to send its mail. That makes it an excellent way to detect address forgeries, a favorite spammer tool.

One of the early questions raised about SPF was: won’t spammers just buy their own domains and set up their own SPF records that say it’s all OK? You can read the answer in the SPF FAQ, but the short version is: Yes, they will, but it won’t give them a free pass.

Email servers: how not to do it

I run my own mail server. I don’t consider myself an especially skilled administrator, so I shouldn’t point fingers. However, in recent weeks I’ve had the following experience more than once.

  1. A delivery-failure message arrives from an unfamiliar host.
  2. The (quoted) orginal message is nothing I ever sent.
  3. The recipient is unfamiliar to me.
  4. The “sender” of the original message is an email address I control, but not one I ever send mail with.
  5. OK, so this is backscatter.
  6. I email the postmaster suggesting they learn how to avoid sending it.
  7. The message to the postmaster bounces back because of some server misconfiguration.

Argh! Nothing spoils the catharsis of a good complaint like a bounce.

Attachment-viewing script for mutt

My primary email client for my e-scribe mail is mutt. This came about in an almost accidental way.

Last summer I moved all my websites and mail to a new server. As I was setting it up I realized that I had an opportunity to decide that no passwords for this box would ever be sent in the clear. No telnet and no FTP, that was easy. But given the hassle of setting up encrypted mail authentication, I had in the past let that one slide. So I decided that until I set it up properly, I’d use a terminal-based mail reader over SSH. No unencrypted POP3 or IMAP for me. I looked around and decided mutt looked good.