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Archive for February, 2008

YouTube BGP Disappearance

Monday, February 25th, 2008

YouTube disappeared from the Internet on Feb 24 after a Pakistani ISP tried to block it by advertising a more specific route in BGP.

BGP is used mainly for routing, but you can also do geographical load-balancing with it.

It’s unlikely that secure BGP will take off anytime soon because of the overhead involved.

But companies may consider advertising only /24 blocks to prevent others from being able to advertise more specific routes. The downside to that is bigger routing tables and more memory required to hold them for everybody.

cnet.com: How Pakistan knocked YouTube offline (and how to make sure it never happens again)
arstechnica.com: Insecure routing redirects YouTube to Pakistan
NANOG thread: YouTube IP Hijacking
Internet-Wide Catastrophe—Last Year

Free Keynote Internet Health Report
Renesys Blog
BG4.AS
BGPlay
wikipedia: BGP, Autonomous System
cnet.com: YouTube disappears from the screen temporarily

Posted in Business, Tech | 1 Comment »

300 Terawatt Laser Photo

Monday, February 18th, 2008

One of the things that American universities do well is Big Science …

One of the nerdiest photos I’ve ever seen, a 300 terawatt laser:

Credit: Anatoly Maksimchuk, associate research scientist in the Department of Electrical Engineering and Computer Science.

physorg.com: Michigan laser beam believed to set record for intensity

Posted in Tech, Toys | No Comments »

linux iotop

Sunday, February 17th, 2008

Since IO accounting was added to the linux kernel in 2.6.20, it’s been possible to examine IO per task.

Guillaume Chazarain’s iotop.py takes advantage of that to show disk IO in a format similar to the venerable top program.

It’s unlikely yum install iotop will work on your older linux distro yet though …

Prerequisites for running iotop.py are Python 2.5+ (to preserve your existing python install, do make altinstall) and linux kernel 2.6.20+ with IO accounting enabled (TASKSTATS and TASK_IO_ACCOUNTING.)

make menuconfig

General setup --->
[*] Export task/process statistics through netlink (EXPERIMENTAL)
[*] Enable per-task delay accounting (EXPERIMENTAL)
[*] Enable extended accounting over taskstats (EXPERIMENTAL)
[*] Enable per-task storage I/O accounting (EXPERIMENTAL)

iotop.py accepts several command line options for filtering, including PID, user and process/thread-view. Once the program is loaded you can use the keyboard arrow keys to change which column gets sorted.

Guillaume Chazarain’s blog
Linux::Taskstats::Read Perl module
Tricks to diagnose processes blocked on strong I/O in linux
DTrace iotop
DTrace iotop samples
Running DTrace from Solaris Against Linux in Brandz
Fedora Daily Package: iotop – Display I/O Activity by Process

Posted in Linux, Open Source, Tech | No Comments »

Ruby Test Automation Tools

Thursday, February 14th, 2008

I was talking to a QA Manager friend of mine today, and got his opinion on test automation.

I wasn’t surprised that his opinion was similar to mine, but surprised they were basically identical.

Test automation is:

ok for APIs, less so for UIs
no panacea or replacement for manual testing
real programming
too painful if your app is not prepared for testing
inefficient on a moving target.

When I need to do automated web testing, I usually use perl HTTP::WebTest.

He’s been looking around at some Ruby tools, mainly Selenium. RSpec is another. (OpenQA has a bunch of tools on their site.)

AtomicObject is a consulting company with a very interesting webpage on their Ruby testing philosophy and tools.

Another Ruby environment that looks interesting is Heroku.

Posted in Business, Tech | No Comments »

iSkoot Skype Client for Smartphones

Thursday, February 14th, 2008

iSkoot has a Skype voice and chat client for Smartphones.

I installed it on my BlackBerry 8700g and the chat client seems to work ok. No emoticons though.

iSkoot Skype Client for BlackBerry

I’ve been using Shapeservices’ $25 IM+ for Skype client for about 6 months on my Blackberry 8700g for work. Works fine.

Nice to have a free alternative though.

ShapeServices also markets an iPhone Safari-based Skype client now.

ShapeServices Skype Safari Client for BlackBerry

Posted in Business, Tech, Toys | No Comments »

Reliable DVD Data Archiving

Tuesday, February 12th, 2008

Looks like the way to go to archive data on CDs and DVDs is to use Taiyo-Yuden media with software that implements Reed-Solomon codes like dvdisaster and PAR1/PAR2 in a jewel-box in a controlled environment.

QuickPar
Parchive
wikipedia: Parchive
All About PAR
linux.com: Use dvdisaster to protect backups on optical media
How To Choose CD/DVD Archival Media
pcworld.com: Burning Questions: Ten Tips for Durable DVDs
CLIR PUB121: Care and Handling of CDs and DVDs: A Guide for Librarians and Archivists

Posted in Photography, Tech | No Comments »