Hacking a Hallmark Text Band: First Attempt

The Hallmark Text Band is a strange thing: Doesn’t Hallmark know kids have cell phones now? Anyway, it is an extremely simple micro-controller driving a led matrix and a C-Max CMM-9201. You get 10 characters, and a small reed-switch? triggers a hardware interrupt, and broadcasts your 10 characters to a friend, and you swap messages. The devices holds 24 messages, FIFO. Memory is volatile. Profanity filter included. Oh well.

Validating Graphite Metrics With Bash!

At my dayjob I get to work with Graphite and power meters. It is cool: To make it easy for my clients to get power information, I’ve written a command line tool called “power” that they can run to get the power usage for a server when running their program. Here is an example: power METER-NAME sleep 10s Pretty handy. The “METER-NAME” is pretty important, as it lets the script know which system’s power you are interested in.

An IPMI SEL Viewing Shootout!

UPDATE (2015-02-18) Albert Chu from FreeIPMI commented that FreeIPMI does NOT attempt to decode OEM events by default. These are events that are OEM specific, so each motherboard may require a different interpretation. FreeIPMI has a --interpret-oem-data option and possibly in conjunction with the -W assumesystemevent option, to attempt to decode these. Unfortunately I no longer have the motherboard I originally ran these on. I might do a followup post with a new motherboard with similar “issues” and see how FreeIPMI compares to the other tools with these options.

Configuring BIOS Settings With Puppet!

You know what it is like to spend time configuring the BIOS on a a server. You reboot the server, and wait for it to take its sweet time to come back up, frantically push its button, hope that you didn’t miss your chance. Then spend some one-on-one alone time with the interface, making sure you do all the right keystrokes to get the settings you want. Sounds like a bad date.

Building Linux Packages For Kernel Drivers! (dkms howto)

Background Most of the time the Linux kernel does a great job of having drivers you need, but sometimes you need to install a special driver or update an existing module. Running make; make install is all fine and dandy for testing, but for production you want a repeatable process. For me, this means OS packages. (deb/rpms) So, how do you go from kernel module source code => Debian package?

Cool Things to Do After Installing OpenWrt

OpenWrt is the bomb. Think all the power of a full Linux distro on your tiny home router or plug computer. Install an External Root Overlay What the heck does that mean? OpenWrt uses an ingenious system were the root filesystem is a super compressed squashfs, merged with a read/write jffs2 filesystem called the overlay. This maximizes your available space on the device. Instead of using part of your remaining flash for read/write, you can use a larger, external device for the overlay.

7 Underused IPMItool Commands

IPMI is Awesome. But, it is underused. Most sysadmins don’t even enable it. If they do enable it, they probably enable it by manually going into the BIOS, and then probably only using the Web interface. LAME. There is no need to go to the BIOS to configure ipmi. You can use IPMItool to configure it in-band. This is my first underused command: (disclaimer: not all IPMI interfaces / bios versions / hardware platforms are equal.

Carbon Fiber Table

It kinda sucks. No matter how much sanding and polish I do, I can’t get it to look great. It is smooth, however. Corners are hard. Just posting these pics for archival purposes, not to show off here.

Carbon Fiber / Copper Solar Light

A copper tube sculptural with carbon fiber leaves. One of the carbon fiber leaves is a solar panel from a deconstructed solar lamp. The tips of the small copper tubes have the white LEDs. The larger copper tube stores the battery and charge circuitry. I would show pictures of them at night but the sun doesn’t shine much here anymore…

Configuring Nagios Like a Boss!

I’m tired of configuring Nagios by hand. Just tired. I always forget to do stuff. I’ll add a new host, or stick in a raid card, add a new website, whatever, and forget to add a nagios check for it. So it happened. You setup a server, put critical infrastructure on it, but forgot to monitor it. It goes down, bad stuff happens. Your boss asks, why weren’t we monitoring this?