openindia

Centos Network Installation Server

2012-03-15T09:30:00.000+05:30

REMOTE INSTALLATION

from CENTOS6

Required Packages for Network Installation: -

xinetd: -Xinetd-managed applications (like tftp, telnet etc.) all store their configuration files in the /etc/xinetd.d/ directory.
tftp-server
dhcp
syslinux: - pxeboot package
nfs

Installation of Required Packages: - 

xinetd: - yum install xinetd
tftp-server: - yum install tftp-server
dhcp: - yum install dhcp
syslinux: - yum install syslinux

Steps to setup tftpboot: -

# mkdir /tftpboot/

Create the tftpboot directory under root directory (/)

Now some changes are required to vi /etc/xinetd.d/tftp 

           server_args = -s /tftpboot

After installing the syslinux package, pxelinux.0 file will be created under /usr/share/syslinux/ directory. This is required to load & install kernel and initrd images on the client machine. 

           Copying the pxelinux.0 image. PXE Linux image will be available once you installed the syslinux package. Copy this         

           to /tftpboot path as shown below.

          # cp /usr/share/syslinux/pxelinux.0 /tftpboot

Extract the ISO image into a directory which is located into tftpboot.

# mkdir /centos

copy the vmlinuz & initrd into /tftpboot.

# cp /centos/isolinux/ vmlinuz initrd.img /tfptboot

Create the directory pxelinux.cfg under /tftpboot and define the pxe boot definitions for the client.

           # mkdir /tftpboot/pxelinux.cfg

          # vi /tftpboot/pxelinux.cfg/default

default centos

label centos

kernel vmlinuz

append initrd=initrd.img showopts=nfs

install = nfs://192.168.56.1/tftpboot/centos/

save this file using the command (:x, :wq).

default: - this option specify the default os that is to be install on remote machine. Default option should be same as label.

Label: - here you can specify the label of OS that you are going to install.

Kernel: - here u have to specify the kernel name which you copy in /tftpboot directory.

Showopts (show option): -Through which u share the centos image.

install – specifies boot arguments to pass to the install kernel.

DHCP server setup: -

add the following lines in /etc/dhcpd/dhcpd.conf

Allow booting;

allow bootp;

filename “pxelinux.0”

next-server 192.168.56.1; #specify here server static ip address.

NFS server setup: -

vi /etc/exports

           /data/packages/centos6 *(rw) #path of to be shared iso extracted image

restart xinetd, dhcpd, nfs services: -

# service xinetd restart

# service nfs restart

# service dhcpd restart

SETTING ON CLIENT SIDE: -

open BIOS on client machine and then set boot device priority to NETWORK.

save it and reboot the system.

In this way you can install Linux OS on remote machine.

author

pardeep taya

email- bk_pardeep@yahoo.co.in

One more day when I feel shame to be an Engineer.

2012-02-01T09:10:00.000+05:30

No use of boasting about our Engineering, Engineering institute when we make big deals (millions of dollars) for the defense equipment. Read this http://timesofindia.indiatimes.com/india/French-jet-Rafale-bags-20bn-IAF-fighter-order-India-briefs-losing-European-countries/articleshow/11706551.cms.

I think we are leading engineers in the world only on paper like our Indian Cricket Team. There is talent, hardwork and funding too, then why we don't work on R&D. Why we have become a man power instead of brain power ???

Hyper-Threading and Multi-Core

2012-01-21T09:55:00.000+05:30

Hyper-Threading and Multi-Core

Threads

Consider the problem of cooking for a big dinner party. Each dish has its own recipe. You could follow the instructions in one recipe until that one dish is done, then set it aside and start the next dish. Unfortunately, it would take several days to cook the dinner, and everything would come out cold. Fortunately, there are long periods of time when something sits in the oven, and while it is cooking you can prepare one or two other things.

A sequence of instructions to do one thing is called a “recipe” in the kitchen, and a “thread” in computer programming. A computer user intuitively understands the behavior of threads when running several programs on the screen, or when listening to an MP3 file in the background while typing a letter into the word processor. Even a single program can make use of threads. The Browsers has separate threads for every file or image you are downloading, and it may assign a separate thread to decode each image or banner ad that appears on the screen when you visit the New York Times web site.

Some short operations have a very high priority. For example, a pot of rice you just started has to be checked every 30 seconds of so to see if it has come to a full boil. At that point the heat can be turned down, the pot can be covered, and now you can forget it for 15 minutes. However, if you don’t check it regularly at first, it will boil over, make a mess on the stove, and you have to start over.

Computer programs also assign a priority to their threads. As with cooking, high priority can only be assigned to trivial tasks that can be accomplished in almost no time at all. Just as a kitchen has to have timers, and a beep when the microwave is done, so the operating system has to have support for program threads and the ability to connect them to timers and to events signaled when data arrives from the network or another device.

In the kitchen, each task you perform has its own set of tools. To chop carrots, you need a knife and a cutting board. To take something from the oven, you need oven mittens. It takes some small amount of time to set down what you are doing and change. If you don’t change, you will find it is very difficult to cut carrots while wearing oven mittens.

Each thread in the computer stores its status and data in the CPU chip. To switch threads, the operating system has to take this data out of the CPU, store it away, and load up data for the other thread. Switching from one thread to another takes a few hundred instructions, but this is not a problem when the CPU can execute billions of instructions a second while a hard drive or network performs only about 30 operations per second. The overhead of thread switching for I/O is trivial.

If it is a big complicated dinner that one person can simply not get done in time, you need some help. Specific tasks can be assigned to different people. The threads don’t change. The bread is still cooked the same way whether there is one person in the kitchen or two. With two people, however, one can chop carrots while the other peels potatoes.

Modern operating systems support computers with more than one CPU chip. The system assigns one thread to run one one CPU, and another thread to run on the next CPU. The two threads run concurrently. However, such systems are expensive and are typically found only in big servers or engineering workstations. Desktop and laptop computers have come with only one CPU.

Hyper-Threading

As has already been noted, memory delay has become an important problem for computer performance. When an instruction requires data that is in second level cache, it may have to wait a cycle or two. During this time, the CPU will look for other instructions that do not depend on the result of the blocked instruction and execute them out of order. However, out of order execution is at best good for a dozen instructions. When an instruction needs data from DDR DRAM, it will be blocked for a length of time during which the CPU could have run hundreds of instructions.

In 2004, Intel tried to address this memory delay problem with a trick called Hyper-Threading. Rather than duplicate the entire circuitry of a CPU, a Hyperthreading processor simply duplicates the registers that hold all the data that the OS would have to remove from the CPU in order to run a different thread. The OS thinks that there are two CPUs and it assigns two different threads to them. All the registers and data needed to run each thread are loaded into the same CPU chip at the same time.

When both threads are able to run at full speed, the CPU spends half its time running instructions for each thread. Unlike the OS, the CPU doesn't have a view of "priority" and cannot favor one thread because it is more important. However, if one thread becomes blocked because it is waiting for data from the very slow main memory, then the CPU can apply all of its resources to executing instructions for the other thread. Only when both threads are simultaneously blocked waiting for data from memory does the CPU become idle.

Multi-Core

Moore's Law says that every 18 months the number of circuits on a chip can double. About one Moore Generation after Intel introduced Hyperthreading both Intel and AMD decided to spend the extra transistors to take the next step and create two real CPUs in the same chip.

It has always been possible to do this in any 18 month cycle. However, vendors previously decided to use the transistors to make the single CPU run faster, by supporting out of order execution and register renaming.

A Server tends to assign a thread to each incoming user request. Generally all network users are of equal priority, so threading is an obvious choice for Server software. However, desktop users tend to do one primary thing at a time. If you are running a low intensity job like Word or Web Browsing, CPU doesn't matter. However, playing video games, retouching photographs, compressing TV programs, and a few other consumer programs will use a lot of one CPU, and making the one CPU run faster seemed more important.

Engineers ran out of ideas for using transistors to make a single program run faster. So starting last year they started building "dual core" chips with two CPUs. That forced some of the software vendors, particularly the video game makers, to redesign their software to make better use of the second processor.

Two CPUs can do twice as much work as one CPU if you can keep both processors busy all the time. Unfortunately, that is not realistic. Even on a server, the value of each subsequent processor goes down, and on a desktop there just isn't enough work to distribute it uniformly. So while Intel is beginning to show of a Core 2 Quadro chip with four CPUs, it makes little sense to go farther than that.

Heat and Power

Computers are idle a lot of the time. When they are running, there is often only work to keep one core busy. The easy thing to do would be to design a dual core machine where both processors run all the time. Such a system will generate twice as much heat and use twice as much energy. Intel and AMD rushed their first generation of dual core processors out the door, so this is how they operate.

Given more time to do the engineering, you can design multi-core systems to shut down parts of the chip that are not being used. This is critical in a laptop system running on battery, but in today's heat and power conscious environment it is useful for even desktop machines.

Co(re)ordination

Two programs are running on your computer. While they mostly do different things, they may both store data on the same disk and they both display output on the same screen. Internally, the operating system must coordinate their concurrent access to shared resources. At the hardware level, each CPU core must coordinate access to memory and to the I/O devices.

In the old days when Intel had one CPU per chip, coordination between the processors was done by the Northbridge chip on the mainboard. That was a perfectly sensible design. However, when Intel moved to Core Duo, and started to put two CPUs in the same chip, it was no left with the unfortunate consequence that the two CPUs could not talk directly to each other or coordinate activity, but instead they had to go out to the Northbridge chip for every such request.

When AMD came up with the Athlon 64/Opteron design they moved memory management into the CPU. That eliminated the need for a Northbridge chip. Processors where connected to the Southbridge (and thus all I/O devices) and to other processors using HyperTransport links. Each AMD CPU has one CPU, a memory manager, and 1 to 3 HyperTransport managers. AMD connected these five components to each other with a general purpose switch called the crossbar or "XBar" for short. At the time, they may not have given much thought to multiple CPU cores, but this turned out to be an ideal design.

Inside the AMD chip, a CPU that needs data from memory, an I/O device, or another CPU makes a request to the XBar. The XBar determines if the requested data is local (another CPU on the same chip, memory controlled by this chip) or remote (another chip connected by a HyperTransport link).

The use of the XBar to connect devices in the same chip, and the HyperTransport link to connect to external devices, creates a design that is efficient, scalable, and flexible. Recently AMD purchased ATI, a leading maker of the Graphics Processing Unit on a video card. This architecture will let them explore hybrid chips that contain a CPU to run programs and a GPU to handle video, both part of the same chip. Alternate designs combine CPU and some of the Southbridge function to produce ultra cheap or ultra small boards.

googled by

Ashwani Gupta

Convert Default Online Dictionary to Offline in Debian/Ubuntu

2011-12-21T13:48:00.000+05:30

Step 1: Type the following command in the gnome-terminal to obtain the dictionary server:

      sudo apt-get install dictd
Step 2: Then to obtain the dictionary definitions in english, i.e. word materials, paste the following command in terminal:

                sudo apt-get install dict-gcide

Step 3: To add the thesaurus(optional) in the dictionary paste the following command in the terminal:

   sudo apt-get install dict-moby-thesaurus

Converting to local host for Offline Dictionary Access

Step 1. go to the Edit → Preferences
Step 2. Now you have the default dictionary selected. Click the Add button to add the offline dictionary functionality.
Now in the Description add the any name you want to fill. Here it is filled with the “Local Server” and the most importantly fill the Hostname with“127.0.0.1” as shown.
Step 3: Now, all you need is to select the the newly added server (named Local Server here) and then your dictionary is up and running with that of smart thesaurus.

That’s it. We have just made our dictionary good enough, to work even without an internet connection. You can now search for word meanings locally.

OPEN SOURCE CANCER REASERCH

2011-12-06T12:40:00.001+05:30

When it comes to treating, curing, and preventing cancer, modern medicine has largely failed. You could argue that cancer is far too complicated to unravel in the few millenia we have been documenting it. Or that the billions we spend annually on research is far too little. Established incentives and policies that perpetuate research silos certainly seem to slow success.

Medical researchers have been trained in a professional culture where secrecy reigns, where they must protect their own interests. The dominant culture discourages sharing research findings and collaborating on projects. It has become more important to protect vested interests than to take advantage of the huge collaborative network that is available in academia.

This mode of thinking is a bitter pill to swallow for the quarter of our population that will die of cancer. According to the World Health Organization, one in every four deaths is attributable to cancer.

What would happen if cancer researchers were able to adopt an open and collaborative approach like the one that has--for the last two decades--revolutionized software development? What if cancer research could be open source?

Linux has been successful because a large group of people recognized a need and agreed on a process for meeting that need. The brilliance of the open source approach is in the sheer amount of brainpower participating. The open source community shows that the collective intelligence of a network is greater than any single contributor.

While the term is attributed to software development, the idea is not. In fact, some medical research does use this methodology in the same way that Linus Torvalds and others develop open source operating systems. The Human Genome Project, for example, very successfully distributed gene-mapping in efforts to speed up the sequencing of the genome. The HGP teams published their data openly, on the Internet.

More recently, a team of Harvard researchers discovered the power of distributed research. A team led by Jay Bradner at the Dana Farber Cancer Institute discovered a small-molecule inhibitor that showed promise in its ability to interrupt the aggressive growth of cancer cells. The small-molecule inhibitor, called JQ1--after Jun Qi, the chemist who made the discovery--works by suppressing a protein (bromodomain-containing 4, or Brd4) necessary for the expression of the Myc regulator gene. It is a mutated Myc gene that is believed to be at the root of many cancers. Without Brd4, Myc remains inactive. Inhibiting Myc could be part of the key to successful cancer treatments.

With the cells from an affected patient, Bradner's group successfully grew the cancer in mice and discovered that the mice with the cancer who received the compound lived, while the mice with the cancer who didn't receive the compound rapidly perished.

Instead of operating in secrecy and guarding their work, Bradner's group shared it. They simply started mailing it to friends. They sent it to Oxford crystallographers, who sent back an informative picture that helped Dr. Bradners team to understand better how the small-molecule inhibitor works so potently against Brd4.

They mailed samples to 40 labs in the US and 30 more in Europe, encouraging these labs to use it, build upon it, and share their findings in return. As a result of this open source approach, Dr Bradner's team has learned--in less than a year--that JQ1 small-molecule inhibitor prevents the growth of leukemia, making affected cells behave like normal white blood cells. Another group reported back that multiple myeloma cells respond dramatically to JQ1. Still another found that the inhibitor prevents adipose cells from storing fat, thus preventing fatty liver disease.

Bradner has published his findings. He has released the chemical identity of the compound, told researchers how to make it, and even offered to provide free samples to anyone in the medical research community. (If you're a researcher who'd like a sample of the JQ1 molecule, you can even contact Bradner's Lab via twitter @jaybradner.)

Bradner feels his early successes are due not only to the science, but also to the strategy. Using an open source approach, sharing the information about this molecule, and crowd-sourcing the research and the testing illustrates the opportunities that an open methodology can bring to the difficult challenges of medical research and prototype drug discovery.

In his recently released TED talk video, Dr. Bradner explains that he firmly believes that making a drug prototype freely available among researchers will help accelerate the delivery of effective cancer drugs to affected patients.

With more practice—and more familiarity with each other and this kind of collaborative research—scientists can break large, complex, time-expensive projects into smaller, achievable portions. By spreading out those small tasks among many groups, much more work can be accomplished in a vastly reduced amount of time.

Using the old research models, Bradner’s team might have learned that JQ1 affects AML cells in the first year. But it might have been next year before they got to leukemia, and years after that before they realized it also could affect fatty liver. How many years do you think the old approach adds to the development of drugs we need today?

It is time to seriously consider a different model for scientific research–one that directly engages and benefits society, encourages open access and the free exchange of scientific information. The benefit to patients would be enormous.

Googled by

Dinesh Kamboj

How to read complex pointer notations in C?

2011-12-06T09:36:00.002+05:30

Use to below table for reference:

Operator Precedence Associativity

( ), [ ] 1 Left to Right

*, Identifier 2 Right to left

Data type 3

--------------------------------------------------------

Example:

char (*ptr)[3]

Now this will be read as:

ptr is pointer to such one dimensional array of size 3 which contain char type data.

Author:-

Rohit Kamboj

M.Tech, UIET

Why we can't install the ubuntu packages of older versions on new one?

2011-11-01T09:31:00.002+05:30

We have learned working on computers in Windows era. So we are habitual of taking the backup of software packages. But this is not suitable for linux systems. In India, we are using windows XP since 2001, the kernel, library hasn't changed since then. So you can install a software on windows XP today which you have tried it 10 years back. But these software may not work on windows 7. The reason is simple, the environment has changed. The kernel, libraries and other supported software have been changed. The same thing happened with Linux based system. For e.g. for every 6 months we get a new version of the Ubuntu Desktop with new kernel and new version of some of the libraries. So the older packages wont work on it. It's best to install the packages using synaptic package manager. If the internet is not available easily then manage to download the Ubuntu DVD which has all the packages in it which are officially supported by Ubuntu. Once you have the DVD, then you need not to download the packages from the internet every time you install it on a new system. In the Software Sources check the option "CDROM with Ubuntu .....". Try this and let me know the results.

How to compile a linux kernel.

2011-10-04T09:37:00.001+05:30

Compiling a new kernel on linux based distro is not a tough task. You just need to have basic knowledge of Linux programming and administration. Follow these steps:-

1) Download a kernel from kernel.org. Keep in mind, the downloaded kernel should be not be very far in version from the base kernel. To know the base kernel version, type this command "uname -r".
I tried it on Fedora 13 and downloaded the kernel 2.6.36 kernel version.
2) Extract the tar ball. ($ tar -jxvf linux-2.6.36.tar.bz2).
3) Change to newly extracted directory.
4) Execute 'make menuconfig'. Don't try to change any thing in it. Just save it (when you exit this script you will asked to save the changes).
5) Run 'make'. It will take more than an hour.
6) Run 'make modules'.
7) Run 'make modules_install'.
8) Run 'make install'.
9) Reboot your system and you will find an entry in grub boot loader. Enjoy ...)

The above are very much easy to execute. Lot's of changes can be done while configuring the kernel 'make menuconfig'. We will look at those changes in the next post.

Tragedy of our Country

2011-09-22T08:54:00.009+05:30

Being a trainer, I have been asked to clarify the difference between Computer Admin and Computer Programming. Most of the students in my area (Haryana), are so innocent that they do not know the difference between these basic terms. No proper guideline is provided by their Educational Institute. This is not the issue of ones sentiments but its true that our new Engineers are going in wrong direction.

It's been a heart breaking question for us if asked by some Engineers or passing out Engineers as "Admin or programming mein difference kya hota hai ?" How some one can serve his/her country or dream of working in a best multinational company with this type of knowledge. We spend 22-25 years of age to become an Engineer. And after our B.Tech/B.E/MCA/M.Sc., the question remains the same "Ab kya karna hai ?".

Reasons for this issues are:-

1) We study for job.

2) We study for exams.

3) 80% of the teachers, do not have any expertise, they only work to make money, no responsibility of the students.

4) Colleges are in the hand of illiterate people, how they can improve the quality of education ? An illiterate or the person with little knowledge can only destroy the future of young guns and in turn destroy the future of the country. Most of the time they hire retired person of Universities to run their engineering colleges.

5) Colleges are opened as a printing press for currency and they are not for enlightening knowledge
6)Our society wants the children to get the marks, not the knowledge.

Some solutions for these issues:-

1) Study for knowledge, a person with knowledge can get the job, can start a business, can do freelancing work.

2) Study for practicals, money can be made only by doing practical works.

3) The teachers should take their responsibility, should try to teach the syllabus not to finish it.

4) Govt. should not allow any illiterate/non-engineering person to start an Engineering College.

5) Students should be aware of the recent technologies, even if they know the name of the technologies, they can't be called Backward.

I hope that one day everyone will appreciate my feelings.

Vande Matram

How to recover GRUB after Microsoft Windows Installation ?

2011-09-06T17:05:00.002+05:30

I have been asked so many times by the linux newbies "How to recover GRUB after installing XP or windows 7 ?".

To make the Linux distro working (booting) after installing windows on the other partition, we need to re-install the GRUB again. You need a Ubuntu live CD for this purpose. Boot your system with this live CD. Open command line terminal (Application-> Accessories-> Terminal). I am assuming that windows is on first partition and Linux's "/" on second partition. Run the following command.

$ sudo mount /dev/sda2 /mnt

$ sudo grub-install --root-directory=/mnt /dev/sda

The above commands will install GRUB. Now boot your system with the HardDisk. When the system is booted up open the terminal and run the following command.

$ sudo update-grub2

The above command will add an entry for windows operating system in the grub config file.

How to install packages (software) in Ubuntu/Debian using command line.

2011-07-11T09:01:00.001+05:30

Command line is an easy way of installing the softwares on GNU/Linux. Some students come to me and ask for package installation method on Ubuntu. So I just thought of writing few lines on it.

First of all, you must know, most of the packages that will be used on Ubuntu are provided by Ubuntu website itself.
So update the list of the packages. Open the terminal and run the following command.

$ sudo apt-get update

then search a package in the list

$ sudo apt-cache search vlc

.
.

vlc - multimedia player and streamer

Now install the packages

$ sudo apt-get install vlc

What is system programming?

2011-06-30T09:25:00.001+05:30

Most of the University Students are in dilemma about system programming.In each and every seminar conducted by us they ask, "What is system programming ?".The question has a very simple answer "System Programming is Computer Science."
Basically system programming is an art of working inside the Operating System. For example if we develop a Java or .NET program ,we simply use its framework and libs, but in case of system programming we directly talk to the kernel. In simple words, "Working with the system calls is the programming of System."
Linux System Programming is the best way to learn the system calls behavior.

Shame on our Engineering

2011-06-08T09:30:00.003+05:30

What do our Engineers and Engineering firms do.We are spending a big amount to purchase defense equipments and air-crafts. Don't know what our smart Govt. and their R&D firms are doing here ?

>> The Indian government approved a plan to buy 10 C-17 Globemaster III aircraft from Boeing Co. for $4.1 billion, in the nation's largest military transaction with the US. The deal also includes an option for India to order six more C-17 aircraft.
A news from star news web site. click here to check the News.

Why Indian Engineers do not develop any good system software?

2011-05-27T08:39:00.002+05:30

Reasons:
1) We learn theory, not the practicals.
2) We hate C Programming.
3) We love tools, not the technology.
4) Web development is our final destination.
5) We follow USA, we never create our own path.
6) We purchase college projects from outside.
7) Training is just a certificate for us.

But the main reason is, 90% of us do not work hard. Look around, you will find each point mentioned above ,true.

B.Tech/BE Engineer vs B.Tech/BE Graduate

2011-04-19T09:20:00.000+05:30

1) B.Tech Engineer always thinks about Engines and B.Tech Graduate thinks about tools and never look inside the Engine.
2) B.Tech Engineer is creative and B.Tech Graduate is simply a user of those creative things.
3) B.Tech Engineer tries to develop user friendly applications, systems etc. and B.Tech Graduate google them for their ease.
4) B.Tech Engineer never looks on his look and B.Tech Graduate don't leave anything which make him look like a STAR..
5) Girls are attracted towards B.Tech Engineer but B.Tech Graduate have to do a lot to get attention of the girls.
6) B.Tech is not about those 50 exam paper, it's all about learning the Engines.

So Now decide, Do you wanna be a .Tech Engineer or B.Tech Graduate ?

Surfing Internet on ubuntu 10.10 Terminal

2011-04-12T12:11:00.001+05:30

Everyone used to browse website on different web-browser but do you know how to do browsing on Linux Terminal ?
For this there is a tool named as lynx in which you can run any website from in linux terminal.You need to install the tool as follows :-
$ sudo apt-get install lynx

The apt package manager lists the packages that need to be installed. Just press 'y' n then ‘Enter’, for the installation to continue.

After this installation no need to reboot your system. To confirm if it is working , type lynx "name of website " on your terminal.

$ lynx www.google.com

On screen press y for allowing cookies.
It may ask several times to allow cookies.
But don't afraid of cookies because cookies are piece of text stored by a user's web browser. A cookie can be used for authentication, storing site preferences,the identifier for a server-based session etc.

Author

Shivam Rohilla

NIT,Jalandhar

10 Reasons to prefer GNU/Linux over Windows.

2011-02-04T14:11:00.002+05:30

1) Free in terms of money, copying and distribute.
2) Almost virus free.
3) Array of flavors to choose from.
4) New kernel in every 2-3 months.
5) Thousands of application for Education, Development, Servers and Entertainment.
6) No need of license.
7) Amazing 3-D desktop.
8) In built drivers (Specially Intel).
9) Consume less RAM.
10) An out of box Professional Operating System.
Hence Free,Free,Free and Free

Why only 4 Primary Partitions can be created in HDD?

2011-02-02T15:30:00.005+05:30

There is a limit on the number of primary partition on HDD. The reason is the structure of MBR (Master Boot Record). MBR has only 64 bytes to store the partition table. One partition's information will take 16 bytes. So apply your mathematics here and you will find only 4 Primary partitions are possible in HDD. If you create all the 4 primary partition and still you have some free space in HDD, it will become unusable.

To overcome the limit of four partition, you can create an Extended partition in which you can create Logical partitions.And remember Extended partition itself is a primary partition. In this way we can create more than 4 partitions. So next time don't get confused while partitioning your HDD.

Linux Download Links

2011-01-28T12:36:00.016+05:30

Don't look around. Download Linux Distro from here:-

Debian------The most stable Linux distro.
Ubuntu------Linux newbie's favourite.
Mandriva---Easy to manage and lots of graphical tools for administrator.
Centos------Red Hat's clone.
Suse---------Novell supported Linux distro. No need of command line expertise to run this OS,Graphical Interface.
Fedora-------Funded by Red Hat.
Slackware---Freedom to customise each and every thing.
Linux Mint--Out of box Linux distro.
Sabayon

Linux India-Think in a different way

2011-01-27T10:40:00.001+05:30

Free Software, India and Masses

“The Best Things In Life Are Free...”

a famous quote that applies perfectly to the Indian Mindset.

India even in its present stage is a village dominant country. This is evident from the fact that approximately more than 70% of 1200 million Indians reside in villages and remote areas, which means that to bring any form of progress in India one has to tap into this powerful force of remote audience. This also means that if a technology appeals to them, Success of that technology is inevitable.

Consider mobile phones, which when launched in India were available for the rich and urban. Their price being be the major hitch in its mass usage, until Reliance came into this market. Their approach was different; they appealed the remote and village residence by their prices, exciting offers and wide network coverage. It was an instant hit and made a huge profit for them and rest is history.

Now let’s talk about Computers and it’s technology. Microsoft Windows, pioneer amongst Operating Systems in India. Every kid knows about it. Almost every computer user in India has used it at least once. Why ?

Two reasons:

Back in the early Indian Computing days, it was the only horse running in the race.
Free (Pirated) versions have always been readily available.

These made a strong appeal to the Indian Computer users and since then Operating System has been replaced by the word WINDOWS. This scenario still prevails.

Now-days there are other horses (Linux distributions) in the race with free legal products available. Still PIRACY, WINDOWS, IGNORANCE and POPULARITY go hand in hand.

The only hope to eliminate the ignorance is by lighting the candle of awareness about open source and free software amongst villagers and masses.

Awareness is just like common sense, its not that common, Consider Indian schools, I can bet my last Rs. 100/- on the fact that more than 70% do not bother about using original licensed software because They are not aware about the fact that they are giving a lesson of theft to the innocent minds by using pirated software.

In short parents are paying schools to give the education of IT theft to their kids. How can we expect our future generation to respect legal, non-pirated software if we are ourselves not following the path?

I agree we Indians are accustomed of using free (pirated) software, but as my favorite student Vivu says “If you want an unforgettable experience, always choose the road less traveled”.Linux is that less traveled road in the Indian Computing Picture.

Linux (GNU) gives us the freedom to experience and distribute professional softwares, available to every computer with an Internet Connection, without breaking piracy rules.

Thus also helping our children look up to the good ideals of Legal Software Usage.

We talk about awareness and yet ironically we don't have sufficient promoters of Open Source Software in India specially in rural regions.

Buying a software is a foreign concept for a layman and If the country has to progress in the anti-piracy ideals, it must promote the awareness of free and open source products like LINUX.

Linux is easy and a professional Operating System which can do almost everything that any paid operating system can do,

IT JUST NEEDS PUBLICITY,

and Government can help, by spreading aided TV advertisements (Jan hit mein jaari, Issued in public interest) and educational seminars in schools and colleges.

At this point I have to appreciate the fact that the Kerala government has taken the initiative for Educating their children good ideals by implementing legal and free open source softwares in their schools.

Other states should follow the same motive and can take valuable clues from The discussions in past LFY issues (Year 2003 to 2005), covering Linux @ Government, Linux @ Education, Linux @ Hospital, etc.

Some tips that I can think of in the same prospective which can be applied by all educational institutes are:

Every school has at least one programming language in its syllabus. This programming language can be taught on LINUX platform. For example: C, C++ can be taught very efficiently with editors (VI, Emacs, etc), compiler (gcc), IDE (kdevelop, eclipse).

For primary school the computer syllabus includes office suite, painting, surfing INTERNET, general entertainment like games, etc. This all can be done easily on LINUX.

Open office as an office suite
TUX paint as a very good painting tool
Firefox and easy to use network tools provide seamless connectivity
Not to mention the amazing Linux games

(Example: BSNL3G comes with an Ubuntu version (another free LINUX Distributions) for its Internet dialer. SAKIS 3G is also an open source script for various universal gsm, cdma, other connections)

For senior secondary school, the syllabus should include Graphic oriented programming(QT, GTK), Database (mysql, PostGreSQL) and so on. Teachers can be easily trained in the above tools without the need of a dedicated trainer. Reading the manuals provided in the tools/web are enough.

For engineering colleges, students should be motivated to work at the ground fundamental concepts instead of giving them assignments and projects which are generally copied from Internet and are never practically used in any hotels or libraries etc(common projects being hotel management projects, library management , ticket reservation projects,etc) Its simply wastage of Valuable Time and Energy of students.

Following these simple to implement suggestions would result in a better breed of Indians who respect rules, discourage piracy, and would have a better newer technical knowledge than the obsolete ancient technologies being taught at educational institutes, which would evidently pay India great returns.

Now lets face it,Talking is easy, taking stand is arduous. We have discussed about the whole free software and Indian psychology scenario, but it would be an incomplete picture without an insight on how we are trying to take a stand.

We have successfully convinced more than 15 schools and counting to use legal software by helping them to switch to open source software.

You can catch us giving free seminars and tutorials every other weekend to help in the implementation and spreading of Linux at homes and offices. Our favorite part in it is showing off the amazing 3-D effect of compiz to the audience and watch them drooling.

To prove how efficiently programming can be done on Linux, we have developed a complete GUI software solution for schools named “SAKSHAM”. This software was developed from scratch on Ubuntu using front-end (C++ & Graphics QT) and back-end database (mysql).

We are doing our bit to spread the open source revolution and After going through it all, you would also be motivated to do your righteous deed, which is, USE FREE SOFTWARE – JUST DON'T USE FREE PIRATED SOFTWARE.

Installing Proxy Server In Ubuntu

2011-01-24T16:54:00.001+05:30

Intro

Installing an HTTP proxy cache on your computer can bring several advantages:

It allows sharing of the Internet connection.

The cache will display pages faster, even if you do not share your connection.

It allows to optional filtering utility.

Polipo is an efficient and lightweight HTTP proxy cache.

Quick Installation

sudo apt-get install polipo

Then just configure the software (web browser ...etc) to use localhost:8123 as proxy.

Note that polipo is accessible only from your machine , thus reducing security constraints, however there is more room for modifications or any alternative configurations.

Among the options are:

*Setting the memory and disk cache

*Automatic filtering of HTTP headers such as user-agent, http-referer.

URL filter.

Allowing hosts on the LAN to connect

If your LAN is 192.168.0.0/24 and your proxy server 192.168.0.1, edit the following file /etc/polipo/config and add the lines:

proxyAddress = "192.168.0.1"

allowedClients = 127.0.0.1, 192.168.0.0/24

Then type sudo /etc/init.d/polipo restart to take into account the new configuration.

Changing the port

To change the port on which Polipo listen, add the following proxyPort parameter to: /etc/polipo/config

proxyPort = 3128

Remember to sudo /etc/init.d/polipo restart to apply changes

Use a proxy server parent

If you want Polipo sends its own requests to another proxy, add the following parameter:

parentProxy = "squid.example.org: 3128"

Using an alternative DNS server

For enhanced performance, Polipo makes its own DNS resolutions without the use of the operating system.

It uses the DNS registered directly in /etc/resolv.conf.

But you can request that Polipo use other DNS servers (e.g. to use OpenDNS). Simply add the following parameter:

dnsNameServer = 208.67.222.222, 208.67.220.220

Disabling IPv6

If you are not using IPv6, add this parameter:

dnsQueryIPv6 = no

More info

The main problem with polipo is its tendency to retain pages to much and this can cause problems for sites where you'll have to login (Kioskea.net)

Be Smart ,Save Your Money

2011-01-23T17:44:00.007+05:30

Please spend a minute and know what you are loosing right now in your company.

I promise you , I will tell you how you can save your money for the company at the end.

Microsoft windows 2008 ------------------minimum price 30,000

Enterprice edition---------------------------- maximum price 1,71,900

Client Access Licenses (CALs) may or may not included.

In order to purchase CAL need to spend -------- minimum 10,000

windows 2010 office pack -------------------minimum 4,250

-----------------------------------maximum 23,700

Need to protect with antivirus

-------------minimum 1500—every year need to renew

Windows 7 --------------------------------- 8,200 to 11,000

hence if you are planning for windows server then total cost

may be ----------------------------------41,000--2,00,000

for windows client with win 7 and other softwares ,you need to

pay nearly---------------------------minimum 13,950 per machine

and over all hardware cost extra ,maintenance extra

So what are the steps to save our valuable money.

On client side we can use Ubuntu--------------- cost-00

open-office (for word,excel....)------------------- cost-00

anti-virus----no need------------------------- cost-00

low hardware configuration,again saves money.

Total cost on client side -----------------cost-00

On server side

again can use Ubuntu with NO PRICE

saved money can be used for other research and development.

***************************************all figures in RS.

Interesing facts

2011-01-04T16:53:00.002+05:30

* A sad soul can kill you quicker,far quicker,than a germ.

* When people become unemployed or suffer economic setbacks,they gain weight.

*Germany and Japan have attained modern,efficient economies with far less inequality than we have--and far fewer social problems.

*If you fail to avoid high inequality,you will need more prisons and more police.

I am afraid I am not free

2010-12-31T18:20:00.000+05:30

Today at the last day of the year I am going to share a very interesting fact.We are living in democracy but do you really think that we are independent and leaving in democracy?
Now-a-days we cannot move freely in our country.Any body can inquire and can say that you are danger for the country if you do not carry ID PROOF.We want to celebrate the New Year but we can't because the New Year is generally celebrated by the terrorists.
So we are independent but we need to be at home and not allowed by the govt.to roam freely but some are not Indians but independent,so are allowed to roam freely and can do anything what they want but we can not.

Please share your views.

Migrate to linux

2010-12-27T15:24:00.004+05:30

One of my friend says that why we are paying money to Microsoft for windows if we can run our computers for free using Linux. People believe that Linux is hard to learn but nothing is hard in computer. Migrating to Linux can even saves our money and can benefit the country.Lots and lots of dollars are paid to Microsoft by the Indian public and government.This can be stopped and in return we will be benefited as we do not have to pay for Linux.