Wednesday, December 12, 2007

Laptop Does Not Mix Well With Water

So I poured a cup of water over my laptop Tuesday morning. Poured it across the back of the screen, really. But I heard sizzle and pop at some point. Unplugged it. It shut down. Took out the battery.

But I opened it up and let it dry for a day and it works fine on the power cord. Have yet to test it on battery. *crosses fingers*

I scared myself when I plugged it back in a few hours after the accident and the computer wouldn't start up. Thought I'd be buying another laptop.

I'm going to set up a backup scheme. I've told myself this before without follow-through, but I'm pretty sure I'll get around to it this time.

Thursday, November 22, 2007

Goodby, Mathworks

I uninstalled Matlab on my laptop today. I love the product itself, but hate the activation mechanism. I had already gone through it when I installed the student version of Matlab on Windows then again when I reinstalled with Linux on my laptop. But for some reason or another my activation was invalid when I recently checked it. Maybe I shifted around a partition or maybe I just sneezed the wrong way.

I couldn't validate old copies of Matlab or install new copies. I went through Mathwork's web interface for managing activations and it didn't help. So I filled out a support ticket to Mathworks to help me resolve this. In the meanwhile, I started working on an alternate way of doing my project. Three days later, an email arrives from Mathworks asking for the MAC addresses of my computers. I never bothered to send that information.

If I wanted to be treated like I was a dishonest thief, I would have borrowed a pirated copy of Matlab from any one of many students who have downloaded one off the net. All I need for this software to do is work - to do useful things for me. Now I don't need it because I already switched to a method that doesn't require Matlab or any solution like it. Even if I do need an application like Matlab again, there are alternatives that don't require me to waste time like this.

So goodbye, Mathworks. It was fun while it lasted.

Tuesday, November 20, 2007

Doritos: 4/2.625=0

I chuckled as I looked up the Iron content of this 2.625 ounce bag of Doritos. The entire package contains 4% of recommended daily intake for iron. One serving size (1 oz.), which is more than one third of the whole bag, apparently contains 0%.

I considered whether rounding could account for this but sadly (comically?) it cannot.

Saturday, November 17, 2007

OpenWRT WPA Gives Me Problems... and WEP Works!

So I thought WPA was working perfectly. But then it started dropping out on me every now and then. I can't find a pattern to it. But I did leave the SSH connection to the router open on my desktop and the error message "wl0: Invalid argument" was displayed repeatedly.

Sometimes the connection get reestablished after a while. Sometimes I get impatient and reboot the router.

So I gave the instructions for WEP setup on OpenWRT Kamikaze one more try, except this time instead of using my old WEP key I followed all the steps and generated a new key as instructed. And now 128-bit WEP works! I'll have to see if it's stable but I'm hopeful.

Also, "Encryption key:<too big>" still appears when I run "iwconfig". Maybe 128-bit key is too big to display in what they allocated for the field to use? I dunno.

Wednesday, November 14, 2007

OpenWRT WEP Trouble

I had some trouble with enabling 128-bit WEP encryption on OpenWRT Kamikaze 7.09 (kernel 2.4). I'd run iwconfig and see "Encryption key:<too big>" but could not figure out how the key could be too big as I entered into "/etc/config/wireless" file, under "key" option, a 26-digit hexadecimal number as the WEP key.

As to be expected someone else ran into the same problem and discussed it in OpenWRT Forum and references a link with the solution. The solution did not work for me, though.

So I followed the instructions here to use WPA instead of WEP. It's working great. Don't know why WEP wouldn't work.

Afterthought: The router I am using is Linksys WRT54GL v1.1. I didn't try WPA2.

Sunday, November 11, 2007


Installed OpenWRT on my wireless router (Linksys WRT54GL). Default firmware from Linksys wouldn't do DHCP and static IP allocation at the same time. At least I couldn't find a way to do it.

Default installation of OpenWRT does not come with an HTTP server so all configuration is done over SSH sessions. I could always install a web server with configuration manager but it works well as it is.

Spent a good chunk of my time with configuration. One problem I had was that I was following instructions for configuring a previous version - White Russian - rather than the current - Kamikaze. Information on getting Kamikaze to do what you want seems rather fragmented. Might be because it's new.

Plan to get it to update DynDNS domain and forward some ports to my desktop.

The desktop was given a static IP by configuring DHCP on the router. I found a discussion about setting up and troubleshooting static IP addresses. I configured dnsmasq by adding MAC-IP address mapping in /etc/ethers file (and made it readable by user "nobody").

Other links:
Configuring DHCP and DNS on OpenWRT