Saturday, December 30, 2006

Notes on recent AOLserver research

I'm looking into using a flash (xmlsockets) gateway to implement low latency connections between the browser and the server (Aolserver), in short, an implementation of COMET using a flash component.

I must admit that creating a socket server in AOLserver is not as straightforward as say in Apache with PHP or CGI perl but my research has led me to a number of different (possibly unrelated but potentially usefull) things.

Memcached : Someone has written a tcl api to memcached. Memcached caches db requests for clusters of AOLservers. It can run as a daemon on an unused server and allow several clustered web servers to share a cache of db requests. I was particularly intrigued that LiveJournal .com uses it with positive results. Dave suggests that it would be neat if this could be augmented into ns_cache.

Naviserver : I've known for sometime that there is a fork of AOLServer. I just noticed that they have lots of potentially useful modules. Some of these are familiar AOLServer modules. I would be interested to find out if any of these modules will work on AOLServer 4.0.10 and 4.5. Another intriguing question is whether OpenACS can run on NAVISERVER.

Saturday, December 23, 2006

One year of blogging

One year and 6 days ago was when I signed up for a blogger account and made my first post.
85 blog posts later who would have thought that it would still be here :-)

I hope next year will be a great year for blogging ...

Wednesday, December 20, 2006

Embed an encoded file in the URL

In additon to http, https, ftp etc. This guy discovered a protocol "data". I would be interested to know how we can take advantage of this in Ajax Applications.

He lists a couple of possible applications. Click on the title to jump to the article at Hackzine.

Sunday, December 17, 2006

they posted my article

I do a lot of geeky stuff for fun. One of the articles I wrote about one of my projects just got published at the PinoyTech Blog. :-)

Upgrading to a larger hard disk

For several weeks my hard disk has been making a clicking sound. I couldn't reboot anymore because the clicking sound becomes worse during boot up and I got really worried that one day it wouldn't boot at all. It's my 4 year old Western Digital 40GB 7200rpm hard drive. I've been using it as my root partition for the last year and I think it's saying its last prayers.



In the past, upgrading to a larger hard disk for me was always an opportunity to reinstall everything and start with a new OS. This time, however, I can't afford to do that because I have a pile of things on my plate that I want to clear out before the end of the year. In addition, I happen to be quite happy with SLES 10 (Suse Linux Enterprise 10) on my workstation and I would be devastated if I had to redo all my settings and configurations.


I went to the mall and got myself a new hard drive. It's a Seagate Barracuda 7200.9 160GB 7200rpm with 8MB cache. I would've wanted a Barracuda ES but it's available on order basis only and I didn't want to wait too long.



So here's the sitch ... I have an old 40GB hard drive that's about to give and I want to upgrade to my new 160GB hard drive but I don't want to reinstall my OS.

Thank goodness for the internet, to everyone who likes to post about their problems with their hard disks and best of all to everyone who answers.

So here's what I did.

First, I turned off the computer and unplugged it. My motherboard supports both SATA and IDE interfaces. I installed my new hard drive and plugged it into SATA1.


Next, I boot up my PC and enter the BIOS. On my PC, I just press the delete key while it's booting up. Then, I configure the hard disk boot sequence so that it boots from SATA instead of the IDE interface. Note that not all motherboards supports this feature. While I am in the BIOS, I also configure the CDROM to boot first, you'll find out why next.


I used a Xubuntu Live CD to boot the PC after the configurations I made to the BIOS. In Xubuntu, I open a terminal and executed the following.




dd if=/dev/hda of=/dev/sda



My old hard disk is detected as /dev/hda while by new hard disk is /dev/sda. The dd command will copy my old hard disk into my new one byte per byte including the master boot records. There are some people that will argue that the above command can be used ONLY to clone two hard disks that are exactly the same so I was cautious but the explanations weren't very convincing so I decided to take a risk.


The copy took a while to finish. After it was done, I used cfdisk to verify the partitions on my new hard disk



cfdisk /dev/sda




From cfdisk I can see that I have a 40GB partition and about 110GB free disk space. I converted the free space into a new partition. I saved the configurations and exited cfdisk. Note that I could also have opted to resize the existing partition to use the entire disk.


I then ran fsck on /dev/sda1 which is the new partition which is the copy of my old hard drive. fsck did not report any problems.


Before rebooting, I mounted /dev/sda1 into a temporary directory.


cd /
mkdir tmpdir
mount /dev/sda1 tmpdir


Then I went into /tmpdir/boot and proceeded to edit the following files.

  • /boot/grub/menu.lst
  • /boot/grub/device.map
  • /etc/fstab

I changed all instances of /dev/hda1 to /dev/sda1.


I rebooted the PC and crossed my fingers. I was welcomed by the familiar grub menu and it proceeded to boot SLES 10. I logged in and it was like nothing changed.




Helpful Links

http://forums.gentoo.org/viewtopic-t-72947-highlight-cfdisk.html

http://www.linuxquestions.org/questions/showthread.php?p=1848006#post1848006

http://en.wikipedia.org/wiki/Dd_%28Unix%29

Tuesday, December 12, 2006

Dreamweaver, eat your heart out !!! Here comes Aptana.

The founder of Aptana demoes how easy it is to use Aptana's Web IDE to develop Ajax applications using YUI.

Debug Javascript with Firebug

If you've never heard of or used firebug, on which rock have you been hiding under all this time :-)
Joe Hewitt introduces you to Firebug on this video.

Monday, December 11, 2006

Are you an INTJ ? Take the test and find out.

Click the title link. It will bring you to a page where you can take an online test to determine your personality.

Nope, don't worry, it's not from COSMOPOLITAN or some women's magazine ...

Saturday, December 02, 2006

Encounters with IE

Aside from the preparations for the super typhoon that did not hit manila. This week was full of encounters with Internet Explorer.


1 - Operation Aborted error when printing a Web page. This happens on IE 6 only. If you happen to use "Tags" as an input name, you're users are bound to get the Operation Aborted Error.


2 - Page can not be displayed error. I couldn't find the original blog article where I read this particular problem. It occurs on a webpage where you have inline javascript that is trying to manipulate an html element that has not been loaded yet. The solution is to put the javascript in a function that gets called on the window.onload event.

Reming missed Manila

We are all thankful in Manila that Reming changed course. It's bad news for the Bicol region, though, especially in Legaspi, Albay where Mayon volcano is. They are now dealing with the aftermath of a super typhoon in addition to a possible eruption.