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Converting Mbox to Maildir

MBox is the original and ancient format for storing mail on Unix systems, it consists of a single file per user under /var/spool/mail that has messages concatenated. Obviously performance is very poor when deleting messages from a large mail store as the entire file has to be rewritten. Maildir was invented for Qmail by Dan […]

Mail Server Training

Today I ran a hands-on training session on configuring a MTA with Postfix and Dovecot for LUV. I gave each student a virtual machine running Debian/Jessie with full Internet access and instructions on how to configure it as a basic mail server. Here is a slightly modified set of instructions that anyone can do on […]

Postfwd and Local Only Email

Over a year ago when I was considering my first Android phone purchase I setup a test account on my mail server so that I could test email clients on phones and tablets. I used a short password because I didn’t want to type a lot on small screens and because typing a password into […]

SASL Authentication and Debian/Wheezy

After upgrading a mail server to Debian/Unstable (which will soon be released as Wheezy) I started getting SASL errors.

535 5.7.8 Error: authentication failed: no mechanism available

The SMTP protocol gave the above error for both LOGIN and PLAIN methods.

SASL LOGIN authentication failed: no mechanism available

The postfix/smtpd process logged messages like the above […]

Some Postfix Scripts for dealing with Outbound Spamming

I’ve just written some small scripts to help me manage spam emergencies on a mail server. I’ve been doing this thing with a bit of manual effort for a while, but after having done it once from a phone I want to optimise it a bit to reduce painful typing.

My observation is that when […]

Why Cyrus Sucks

I’m in the middle of migrating a mail server away from the Cyrus mail store [1]. Cyrus provides a POP and IMAP server, a local delivery agent (accepting mail via LMTP). It is widely believed that Cyrus will give better performance than other mail stores, but according to a review by linux-magazin.de Dovecot and Courier […]

Maildrop, IMAP, and Postfixadmin

I have recently configured my mail server to use IMAP. I started doing this when I was attending Linux.conf.au so that I could read urgent mail using my EeePC while at the conference and then be able to deal with the more complex stuff using my laptop later on.

The next logical step is to […]

I need an LMTP server

I am working on a system where a front-end mail server sends mail to what it considers to be a LDA (Local Delivery Agent) which actually sends mail to a back-end server via LMTP. I can’t remove that fake LDA from the design because it does a bunch of business specific processing along the way.

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Do Spammers target Secondary MX Servers

Rumour has it that some types of spammer target the secondary MX servers. The concept is that some people have less control over the secondary MX server and less ability to implement anti-spam measures. Therefore if they accept all mail from the secoondary then a spammer will have more success if they attack the secondary […]

Please Turn off Your Spam Protection

Hi, I’d like to send an email from a small domain that you’ve never heard of or from a big ISP that’s known for being slack about spam (*), I can’t send the mail to you because of your anti-spam measures. I think that this is unfair, it’s discrimination, and you are cutting off your […]