Archive for the ‘Misc’ Category

Differences between Virtual Private Servers and Dedicated Servers

Monday, August 17th, 2009

This article describes the differences between a Linux VPS and a Linux Dedicated Server from the perspective of Linux system administration and basic functionality. The information presented here is not all-inclusive, nor will the technology behind these differences be discussed.

Linux system administrators seeking a comprehensive guide to their virtualization platform of choice should consult the OpenVZ Documentation or Xen Documentation.

Contents

Fundamental Differences

The following differences can be noted on either the OpenVZ or Xen virtualization platforms:

Kernel and Hardware Differences

  • Modified kernels are not supported at VPSLink
  • All hardware is virtualized - Hardware clock may not be modified

Hardware clock workaround: VPSLink runs NTP on all hardware nodes to ensure server time is reported accurately. Setting the Linux System Timezone is a reliable way to synchronize your VPS time with your local time.

Network Interfaces and Hostname Reset on Reboot

  • Network interface changes are reset when the VPS is rebooted
  • Server hostname is reset when the VPS is rebooted

Configuration reset workaround: Add configuration commands to your /etc/rc.local file to reconfigure your VPS whenever it is booted.

OpenVZ Platform-Specific Differences

  • C libraries may not be modified on OpenVZ
  • Resolver nameservers are reset on reboot
  • Kernel modules may not be installed and installed kernel modules are not visible within the virtual environment (see VPSLink OpenVZ Installed Kernel Modules for details)

Any allocations in excess of your VPS memory limit (RAM) will result in processes being killed on OpenVZ - please see the Problem: Process or Daemon Dies article for more information on OpenVZ’s behavior and troubleshooting.

Xen Platform-Specific Differences

  • C libraries may not be modified on Xen unless the modification is performed on a non-thread local copy of the compiler

Source: http://wiki.vpslink.com/Differences_between_Virtual_Private_Servers_and_Dedicated_Servers#Fundamental_Differences

Jokes For Web Developers

Monday, August 17th, 2009

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chmod a+x /bin/laden  -  allows anyone to execute Bin Laden

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Make a Div a Link

Sunday, August 16th, 2009

Few days ago, I was looking for the best way to make a DIV into a link when I came across this website: Almost Effortless!. The author showed how to make a div a link with a little bit of Javascript (see article). It is actually pretty simple:

The Javascript Technic

1. <div id=”header” onclick=”location.href=’http://www.example.com’;” style=”cursor:pointer;”> </div>

<div id=”header” onclick=”location.href=’http://www.example.com’;” style=”cursor:pointer;”> </div>

By this method, the whole block is clickable with just a single line of code while, with CSS, you will need to set few parameters to get the same result. Pretty cool, no?

Here is the CSS technic:

Now, let’s see how it works with CSS.

First, put a link inside your div

<div id=”header”><a href=”#”></a></div>

…and now set the link’s display property to 100% to fill the DIV in your stylesheet:
view plaincopy to clipboardprint?

1. #header {
2.   width:300px;
3.   height:100px;
4.   border: solid #EEE;
5. }
6.
7. #header a {
8.   display:block;
9.   width:100%;
10.   height:100%;
11.   text-decoration:none;
12. }
13.
14. #header a:hover {
15.   text-decoration:none;
16.   background-color: #EFEFEF;
17. }

#header {
width:300px;
height:100px;
border: solid #EEE;
}

#header a {
display:block;
width:100%;
height:100%;
text-decoration:none;
}

#header a:hover {
text-decoration:none;
background-color: #EFEFEF;
}

Conclusion:
As you can see, the Javascript technic is faster than the CSS one but keep in mind that some people might disable Javascript in their browser and won’t see the link

Japanese On Xubuntu

Sunday, December 14th, 2008

Applications > System > Language Support > add ‘Japanese’ as a supported language

My First Linux Disaster

Tuesday, August 21st, 2007

Yesterday I wished just to delete all of my songs on my MP3 player. How to do that? Simple.

rm -r *

The problem comes when, by mistake, your current directory is /.

I wasn’t so quick in pressing CTRL+C. The disaster! My file system completely blank!

I thought it would never have happened to me!

Why was I logged as root while acting on my MP3 player? Because I’m very stupid! :-)

That’s all.