Month: September 2008

Reverie: A DSLR Masterpiece in HD

Yes, I am busy again that’s why I have been so quiet.

As usual Rizal pointed me to an interesting post that leads me to Reverie. It caught my attention so much I had to write this short post.

I was astonished by the quality of the movie, especially since it is taken using a 21 megapixel DSLR. Yes, it’s too expensive and no, I will not buy it and no, I didn’t develop a passion to make films after seeing this movie.

By the way, it’s not the movie that matters for Reverie, it’s the quality of the picture.

Setting DD-WRT Cron Job Through Command Line

I managed to get OpenVPN running on my DD-WRT v2.2 router, with the instructions from the wiki.

However after a few reboot tests I saw that OpenVPN died immediately after it started, with no traceable reasons.

Sep 12 00:51:10 192.168.xx.xx openvpn[3940]: TUN/TAP device tap0 opened
. . .
Sep 12 00:51:11 192.168.xx.xx openvpn[3949]: Initialization Sequence Completed

I suspect it has got to do with the fact that my ppp0 (ADSL) connection takes some time to activate.

So I thought of doing a check using cron – if OpenVPN is not running, run it.

The command I wrote was:

But the bad news is that when I enter this command in the cron box inside the Web Administration GUI the single quotes get translated into the HTML entity, and this becomes permanent in the nvram and also in /tmp/cron.d/cron_jobs. Damn.

So I thought of using the command line. Here’s what I did in the SSH shell:

At this point if you don’t want to reboot your router, enter these into /tmp/cron.d/cron_jobs and restart cron using stopservice cron && startservice cron.

And I’m all set!

I hope the IT team from my company is not reading this, but I also have a vpnc daemon running on the router to connect to my company network and I do the same check as above 😉

OpenVZ On Ubuntu Or Debian

As a SysAdmin I have been using OpenVZ since it was introduced, and trust me it has not always been this easy. I used to take care of 20 physical servers with yearly replacement of about 5 machines. Since some of the servers are running different Linux distributions and different hardware it was decided that to standardize all servers, OpenVZ was to be deployed so that all of them are running Debian stable.

OpenVZ is container-based virtualization for Linux and it only separates the different guest servers in terms of resources. This differ from other implementations such as VMware, Xen, and VirtualBox where these involve hardware virtualization. Because of this, the guests called VE or VPS have the same kernel version and can only run Linux. What distribution as guest? The choice is yours.

Undoubtedly most of you have heard of Virtuozzo – it’s running OpenVZ. As a matter of fact the company that produces Virtuozzo is the one funding and supporting the development of OpenVZ.

The fact that it can run any distribution you like means that you can study and learn how to maintain different distributions. Even the littlest difference can confuse a rookie SysAdmin, for example:

  • Debian apache’s init script is distributed as /etc/init.d/apache and /etc/init.d/apache2 while in CentOS it’s called /etc/init.d/httpd
  • In Debian to change init scripts and runlevels we use update-rc.d while in CentOS we use chkconfig even though they both do the same exact thing

There are many other differences in terms of implementation that I rather not discuss here.

Click on Continue Reading if you’re interested to read more…
Continue reading OpenVZ On Ubuntu Or Debian

DD-WRT v24 Upgrade on My WRT54G v2.2 Wireless Router

It has been some time that I wanted to upgrade the firmware, but I rarely have the motivation to do so. I ensured myself that I would not brick the router, and reminded myself on how DD-WRT always produces new and exciting features. So today, I did it. It took around 20 minutes to upgrade and re-configure my router. I have a significant number of customization done especially the QoS and port forwarding and they take a while to be reconfigured. Unfortunately I can’t import saved settings from the previous version of the firmware.

Since I have a WRT54G v2.2 (antique), I followed the advice from the Internet – upgrade to mini version and then to standard version.

One of my favorite addition is the ability to see how many connection each client is using:

Another feature that I think is cool is the ability to plot a real-time bandwidth graph:

The WAN graph is maxed out because I am downloading Ubuntu from OSCC mirror as mentioned in the previous post.

There are tons other improvements included that I can’t include here, try it out yourself!

Enabling connection to modem to check stats

Since the WRT54G is not a modem, I do sometimes have the need to check my ADSL stats and have to connect to the modem directly. My provider sometimes do cheat by capping my connection lower than what I have paid for.

To enable this I simply add an interface alias to the vlan1 interface on the router. I am using a Linksys AM-300 modem-router as a modem only and it has the default IP of 192.168.1.1. If you didn’t customize your WRT54G then it’s difficult because 192.168.1.1 is also the default IP. In my case, my LAN is in a different subnet (my WRT54G has a customized IP). All I had to do in the web interface is to go to Administration > Commands, enter ifconfig vlan1:1 192.168.1.2 netmask 255.255.255.0 broadcast 192.168.1.255 to the box and click on “Save Startup”. The router will reboot because it is a startup script!

After the router finished rebooting, if I enter the 192.168.1.1 in my browser address bar I will get my AM-300 administration page. Now I can be sure I am not cheated and still get my 2Mbps 😉

OSCC: The Silent Mirror

All hyped out about sharing Linux knowledge with friends especially dirn, I wanted to download Ubuntu for my own use mainly because I am a strict Debian user. Browsing the mirror list in Ubuntu official site I am disappointed by the speed of most of the mirrors I selected, and the fastest I can get is the ETA of 4 hours.

Then a bell rang in my head and I went to look for OSCC. This mirror is the closest mirror I can get using my ADSL. The problem with this mirror is that it sometimes have old files especially for the Debian and CentOS repositories. So it always become my last choice to look for files. I don’t blame them as the rsync process must’ve been really slow to download files from the 1st level mirrors.

The speed is very satisfactory because the mirror is located in Cyberjaya, Malaysia as you can see below:

I have been seeking this mirror every time I feel disappointed with speed of overseas mirror as it mirrors some other projects too.

Historically in 2002 I almost became an employer of OSCC after scoring good marks in a Linux test done at DRB-Hicom, and went to an interview at OSCC. I failed to get the position because when asked “How do you change init scripts and levels in Red Hat?”, I answered “I use ln to make symbolic links from /etc/init.d to /etc/rc.{0-6}”. They said, “No, you should use chkconfig“. My answer was not incorrect being a self-taught Linux user but by-the-book users will feel otherwise. I was annoyed but I don’t hold any grudge against them. I do, however feel lucky I didn’t get the job.

SMART Tunnel Woes

I just watched a segment from TV3’s Buletin Utama about complaints regarding the closure of the SMART tunnel. It amuses me with the fact that people seem to be blaming it on the tunnel management alone when the reason is closure is known – to redirect water.

For the ignorant or the unrelated readers from overseas, the tunnel operates in 3 modes:

  1. Normal – no water flowing. Traffic as usual.
  2. Storm – water flowing in the lower section of the tunnel, allowing traffic in the upper section of the tunnel.
  3. Heavy storm – water flowing throughout the tunnel, no traffic may pass.

I understand the disappointment that came from motorists, but to be fair I think the blame should go to the engineers who planned this project. Perhaps the volume of water that may pass in the tunnel was not correctly projected? From the news what I understand is that since opened in May 2007 the tunnel have been closed to traffic for 44 times now, causing huge traffic jam in the city. Of course, this shouldn’t be the case if the volume of water is not significant and water only pass in the lower section.

The CCTV footage that was shown clearly showed that water level was indeed more than half the tunnel’s height. I am not sure whether anyone can call this project a failure. It may not be perfect but it is indeed preventing flash floods in the city. So we have to choose either one, which is quite fair for me although the original plan was to solve both problems – flood and traffic flow.

Then again, it’s a RM1+ billion project and there is no doubt taxpayer’s money are involved. You be the judge.

MyBlogLog: Where Have I Been?

I am a little embarrassed to admit that I have neglected MyBlogLog for quite some time that I never noticed that it has been bought by Yahoo!.

I did wonder on how some people get very nice MyBlogLog widgets and today I decided to check it out. I was asked to link my account to Yahoo! when I tried to log into MyBlogLog. And as you can see I have activated the new widget.

It turns out Yahoo! decided to leave the old widget codes alone and it has worked all these while 🙂

Old Vs New:

p/s – no offense to Onyx Design I was not trying to delete you but when I captured the screen I had my mouse hovered on top of your icon and too lazy to re-capture.

Google Chrome: More Findings

Actually, if you really watch the 52-minutes video or read the whole manual you might already know about these cool features. And then again maybe not. I didn’t have the time to go thorough with the documents / videos so I am just documenting based on casual use.

One of most obvious feature would be the “Inspect element” contextual menu. As a Firebug user this screen is no stranger to me.

I have not figured out whether Chrome can display real time resources such as JavaScripts and CSS loading like what Firebug does in its “Net” panel.

Another interesting feature I just discovered is the “Open link in incognito window” contextual menu that will appear every time a right click is done on a link.
Continue reading Google Chrome: More Findings

Google Chrome: My Findings So Far

Like Rizal, I was also thrilled to try out Google Chrome when I saw the posts in nazham.com and dirn.name.

I am simply discussing my initial findings, and we all know it’s Beta. This is by no means an official or detailed review. This is what I have encountered so far while using it casually.
Continue reading Google Chrome: My Findings So Far

Ramadhan: McDonald’s Breakfast Starts at 5.00

I have just returned from a short trip to Taman Equine McDonald’s to look for some light food for sahur. It was exactly 4.22 AM when I arrived at the drive-thru. We wanted to have the big breakfast set but the voice on the display said “during Ramadhan breakfast starts at 5.00 AM”.

I said thanks and left. I just want to warn everyone because I’ve never heard of this special change during Ramadhan. A bit disappointed but it’s OK.