Identifying spammers in your shared web service (featuring Postfix, auditd, and iptables)

Over the last week, we’ve been having a problem with spam in our shared web service: Something was sending out lots of low-quality, easily-blockable spam, and the bouncebacks were filling up the Postfix queues in our outgoing email cluster.  The way we tracked down the spammer was interesting, so I’m writing it up here in case it’s of interest to anyone else!

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Developing on El Capitan? Need OpenSSL? Install MacPorts!

I’m right now experiencing the joys of setting up a Perl development environment on Mac OS X 10.11 (El Capitan).  I’ve already talked about the weird linker warnings that appear when building Perl, and I’ve just come across another fun roadblock: A lack of OpenSSL header files.  This is not unintentional, and there is a solution.

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Weird object file warnings building Perl on OS X 10.11 El Capitan

I just recently got a Mac laptop with Mac OS X 10.11 (El Capitan) installed, and one of the things I do in a new system is install a local Perl environment using perlbrew.  It allows me to install and upgrade modules without worrying that I am getting in the way of the system environment.  Problem is, when I built my first perlbrew environment on El Capitan, I saw some weird stuff happening in the build.

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How About This? An Introduction

From time to time (and more often when I have more free time), I wonder “Hmmm, how would I solve [insert problem here].”, and from time to time I think “How about this?”  That’s what I’ll be using this category for, problems that I find interesting, and that my solution might work for.

Am I going to be talking about things that are way out of my depth?  Probably!  Am I going to be talking about problems that have already been solved?  Most likely!  But hey, you never know, it might be useful!