Will Bradley

Hot on the heels of my Arduino Nagios Display, I’ve made a kit version of the LED matrix that is much easier to assemble! It’s daisy-chainable, so you only need however many rows you want. Perfect for workshops where you want to introduce someone to shift registers and LED matrixes but don’t want to buy 80 LEDs per student, while letting them take home something useful yet expandable.

It uses the Arduino ShiftOut tutorial code with only slight modifications to the pin assignments. This allows the boards to be single-sided, meaning the traces are easy to follow for newbies to understand how everything works. It also allows the board to alongside an Arduino Ethernet with no pin conflicts.

The basic kit includes one shield and one strip. Additional strips can be added theoretically forever, but practically limited by the Arduino’s power supply, the shift registers, the circuit traces, and the characteristics of the LEDs and resistors.

If you’re interested in buying some, check out my brand-new store!

I’m also teaching a workshop soon that includes this kit. Below is everything included in that workshop:

Reviewing my system, I realized one script I take advantage of the most is a logging script I made years ago to track logins.

I mainly use it to see who is using which computer, saving on guesswork and coming in very handy when troubleshooting weird problems. It also comes in handy when tracking down an asset or debugging login issues (i.e. if there’s no connection during login, it won’t write to the logfile.)

So here you go, in all its VBScript glory:

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You may realize that giving out admin rights (i.e. adding someone to the Administrators group) is a bad thing. But your boss and/or favorite employee might be demanding that they need them in order to do their job. You feel stuck. What do you do?

First, you need to learn something: the Administrators group isn’t magic. The only reason it can do all the things it can do is because when Windows gets installed, it creates a group called Administrators and grants it a lot of permissions on files, folders, registry, and Local Security Policy entries.
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I recently waded into a debate about whether people in an organization should be given local administrator access to their machines.

Now firstly, this violates the principle of least privilege, which is what all of security is based on. You don’t get it unless you need it; you get the minimal privilege necessary to do your job. Imagine if cashiers could withdraw from the company account, if untrained boot camp grads were given missile launch keys, and if spies told their families everything. Security doesn’t work that way.

Still, it got debated, and someone finally asked what specific dangers they were putting their network in by giving certain people local admin rights.

It’s not a simple question, but I’ve come up with some examples.
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This is a comment I posted on Paul Gregory’s Forbes post about Mr. Buffet’s Secretary’s salary– saying that for her to be paying less than him (assuming a 15% rate) then she’d have to be making over $200k, meaning she’s not such a poster child for injustice after all. (I guess God only has pity for those making more or less than $200-500k?)
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Getting notified by SMS is better than via email, I think, because then you can tell the difference between midnight spam and a server fire. Here’s my command for sending a shortened message (to #yournumber#@YourCarrierSMSGateway.com)

Add these to your commands.cfg and then change your contact settings (usually contacts_nagios2.cfg) to use the appropriate command.
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I like the Whiteline icon set for Nagios’ statusmap cgi, but it’s too big; here it is resized to 40px wide and I added an Ubuntu icon as well.

Download: whiteline.zip

See my earlier Nagios post

Sometimes padlocks, zip ties, sternly-worded signs and keyed ignitions just don’t cut it. Maybe what you’re looking for is something more like…

…a web-enabled RFID interlock loosely based on 23b’s Open Access Control system?
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The Minecraft release party, MineCon, was this year in Las Vegas. In a flash of inspiration, I knew I’d found my first cosplay opportunity. Most people would wear cardboard boxes, which isn’t very Vegas. What Minecraft-themed costume would fit Vegas, aside from old people in sweatpants gambling their retirement checks away? A suit, of course! With a Notch-inspired Fedora, and Creeper-print fabric to tie it back to Minecraft. Hours of sewing later, I’m the proud owner of a Creeper shirt (and fedora.)
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The movie ‘Hackers’ came out in 1995, when I was still in elementary school. So by the time I grew up and watched it (along with the Matrix and Tron) I knew that the kinds of computer visualization depicted in those movies was something I wanted. I’m a very visual person (and I think computers are generally way more cerebral than visual) so I’ve always wanted a more visual, physical representation of computer systems. Imagine if we had a tricorder or sick bay analyzer that could show you every little invisible detail of complex systems like the environment, human bodies, or networks? This is one small step towards that.
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