Installing Fedora Core 3, Part 5

UPS

I have a APC Uninterruptible Power Supply, and so I thought, what better way to run it with linux, than with their native PowerChute Business Edition, for linux! Boy was I wrong.

Apparently (from APC tech support) this software doesn’t run any UPS over the USB link, even though almost all of their UPSes nowadays use USB to talk to the computer. Also it has absolutely no documentation. If you go to the official link on the APC website for the documentation for this software product, it will direct you to one file which is a single page of information entitled “Troubleshooting” which discusses a particular problem with a particular hotfix for Micros0ft Wind0ws. There’s a readme file, but that only tells you how to install it and turn their monitoring agent on, but after that, there’s a whole java web interface that I guess you’re supposed to guess about. (The tech support guy actually told me how to use it.)

A much more civilized approach is to get apcupsd, which after trying to get PowerChute to work, is the equivalent of running through a field of daisies on a sunny day. Or whatever you like doing on a sunny day.

Hot-plugging Devices, or “Where are my USB devices?” or “How I learned to stop worrying and love udev”

If you have to use any USB device on a linux 2.6 system, required reading should be the following: Beginnings of Comprehension and Enlightenment. Especially the latter will help you to take a random generic USB device, and turn it into something far more identifiable, such as /dev/palm, /dev/lp-brother, or even /dev/ups. Much magic happens in /etc/udev, such as assigning device names to loaded drivers (/etc/udev/rules.d) to defining permissions of devices (/etc/udev/permissions.d). And it’s not just for USB. For instance, my nvidia graphics card drivers are loaded by udev and have their permissions also set by udev. Knowing udev means living a richer, happier life with a linux 2.6 kernel.

Another great tool specifically for USB information is usbview. It’s a great help in writing rules for udev. It updates in real time, so you can unplug and plug USB devices and see how they show up.

chkrootkit

Recently on a computer at work we had some jerk trying every common username and password through ssh, and we wanted to be sure that the little guy hadn’t actually gotten in and mucked anything up. A colleague alerted me to chkrootkit, a program you can run to check for “rootkits” which are basically automated hacking programs. It’s the first thing to look for if you’re concerned about someone hacking your system.