Mail log IP address count

The following monster will parse the mail log and report on unique host connections along with a count.

cat /var/log/mail.log | \
  grep ' connect from unknown' | \
  awk '{ print $8 }' | \
  sort | \
  sed -n 's/.*\[\([0-9]\{1,3\}\.[0-9]\{1,3\}\.[0-9]\{1,3\}\.[0-9]\{1,3\}\)\].*/\1/p' | \
  awk '{count[$1]++} END {for (word in count) print count[word], word}' | \
  sort -n

I’ve been meaning to make this change for a while now, and finally got around to it this evening.

I started blogging at back in November 2003 and continued through to May 2005. After that I stopped blogging for a while, but I started again at in August 2011.

The ProgClub blog was imagined to be a group blog, my plan when I set it up was to have all the ProgClub members have an account on the blog, but that turned out to be a pretty poorly received idea. Eventually, and for a long time now, it has just been me (your host, jj5) over on the ProgClub blog.

Since this has become a personal blog, I figured it was time to move it from ProgClub back to, where it all began.

The transition should be seamless, old links should be properly redirected, old logins should continue to work, but if you run into any problems please let me know.


For a long while now I have been having intermittent problems with the audio in my lab. I stream the GoaPsy channel from, and I really love it, but not when there’s skipping! I figured the problem was related to latency and jitter on my broadband connection, and if so, there was little to be done, except to wait for network conditions at my ISP to change.

But this evening I noticed that when I sat close in to my workstation to type the skipping would start. Then if I moved back in my chair, it would stop. I found I could actually cause the skipping to start or stop just by moving around in my chair!

Turns out the problem wasn’t my internet connection, the problem was the bluetooth connection between my laptop and my speakers! To fix the problem I got underneath my desk and moved my sub woofer about one foot to the left. Now when I move around in my chair my music doesn’t skip anymore! Happy days!

Network v4

I have redone my computer network in its fourth (and final?) incarnation. Everything got redesigned from the ground up. You can see some of the (color coded!) cabling here:

The two switches on top (GREEN and ORANGE) support speeds up to 2.5 Gbps, whereas the bottom two switches (RED and BLUE) only support up to 1 Gbps. The white cables on the right are spares, they’re just auxiliary cables which have already been installed and are available if I need them in an emergency.