I’ve gone graph crazy with Munin! After configuring the usual plugins I went searching for ones that graph fan speed and chassis temperature on Dell hardware. Unfortunately, the one I did find was too quick and dirty and so I went ahead and made them myself. They’re useful graphs to have but really I just needed a worthwhile project to continue playing with Python and creating some basic classes.

I recently began scripting in Python using the VIM editor; my editor of choice. In what became a failing effort to keep my sanity I forewent customization of the VIM settings on my personal machines. You see, I’m often tasked with editing files on servers whose VIM settings I can’t customize. I feared that if I were to become overly accustomed to any custom settings then I’d likely blurt obscenities when forced to use a vanilla VIM. Without some tweaking of my vimrc I end up having to manually indent code in Python. Talk about a loss of productivity, having to use the space bar...

Just finished my first Python script. It’s a Nagios plugin to check Dell hardware components via the omreport utility. It’s designed to be used client-side via NRPE (or check_by_ssh). Additional usage information can be found within the scripts docstrings as well as the --help option. Some gotchas: In some instances NRPE will not execute scripts that start with #!/usr/bin/env. In these instances you will need to specify the full path to python . The plugin expects a symlink of omreport in /usr/sbin, you may need to add one if the OMSA install script didn’t. I hard-coded the path...

Just finished watching a Google Tech Talk on Bonjour presented by Dr. Stuart Cheshire. It’s a very simple introduction to Apple’s implementation of zeroconf. Bonjour aka Zeroconf aka Avahi isn’t the evil I thought it was; and I don’t know why I assumed it was evil. I guess it’s a mixture of hating that Avahi is on by default in most RH-based distros coupled with my misconception that bonjour was appletalk rebranded. Appletalk had a reputation for being chatty so I just assumed bonjour inherited that gene. Truth is bonjour doesn’t introduce any non-standard whiz-bang...

I wanted to use a DynDNS address with iptables. Obviously, you need a way to update the iptables rules when the IP of the dyndns address changes. Easiest solution is to cron a script that updates iptables when the IP changes. Here is one such script:

Creating a ramdisk on FreeBSD is straight forward but Google will lead you astray. The main problem with finding accurate results on how to create a ramdisk is that it’s not called a ramdisk. It’s technically referred to as a “memory-based disk” in FreeBSD. To make matters worse the name of the utility has recently changed. It use to be “vnconfig” and is now “mdconfig“. Most of the articles instruct the user to create a startup script run out of rc.local that initializes and mounts the memory disk at startup. However, FreeBSD added proper rc scripts...

After exhausting the official recommendations on tuning Nagios I begain searching for additional recommendations. I found several mailing list archives discussing the use of check_fping in place of check_ping (fping = fast ping). This sounded great since upwards of 30% of our 9000+ checks are ping. The net effect of one second faster per check is significant. Unfortunately, fping is only faster because its default behavior is to send 1 packet. For fping to remain comparable to our existing check it must send 3 packets. In my tests check_fping is actually slower then check_ping. # /usr/bin/time...