All posts tagged UNIX

Linux An Introduction

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Linux is a free, UNIX work-alike designed for Intel processors on PC architecture machines. Linux is not UNIX, as UNIX is a copyrighted piece of Aware that demands license fees when any part of its source code is used. Linux was written from scratch to avoid license fees entirely, although the operation of the Linux operating system is based entirely on UNIX. It shares UNIX’s command set and look-and-feel, so if you know either UNIX or Linux, you know the other, too.

Linux supports a wide range of software, from TeX (a text formatting language) to X (a graphical user interface) to the GNU C/C++ compilers to TCP/IP networking. Linux is also compliant with the POSIX.1 standard, so porting applications between Linux and UNIX systems is a snap.

New users of UNIX and Linux may be a bit intimidated by the size and apparent complexity of the system before them. There are many good books on using UNIX out there, for all levels of expertise ranging from novice to expert.

However, few (if any) of these books cover, specifically, the topic of using Linux. Although 95 percent of using Linux is exactly like using other UNIX systems, the most straightforward way to get going on your new system is with a book tailored for Linux.

Types of Linux:

Following are the main types of Linux which are available:

The various distribution types in Linux.

The types of disk sets for each distribution.

Which distribution sets are important for you

How to look for files on the CD-ROM.

How to get Linux from FTP sites.

How to get Linux from BBS sites.

How to find FTP sites where you can get Linux updates

Linux Distribution:

Several versions of Linux are available, depending on which CD-ROM or FTP site you visit. You can change kernel versions by obtaining the source code for a new release, compiling it, and replacing your existing kernel. You may find several CD-ROM distributions available at your local reseller. Info Magic’s Slack ware release, for example, comes on Your CD-ROMs and bears the name Linux Developer’s Resource. In addition to the complete Linux system, it includes source code, FTP archives, full documentation, several extension products, and demonstration software of commercial applications (including WordPerfect)

Starting Linux:

Starting the Linux system can be as simple as turning on the power switch of your PC. If Linux is configured to auto load, Linux will be up and running after a few seconds. Few systems are set up to run only Linux, though, and even fewer have it boot automatically when the power is turned on. Although automatic startup is convenient, many Linux users prefer to be able to choose which operating system to boot into (if other operating systems are loaded on the system) or to change the . level of access to Linux. You can start a Linux system by using a boot floppy disk or using LILO in one of several configurations.

Linux Hosting India – Past, Present And Future Of Web Hosting In India

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Healthy competition in a business is always an advantage for both the customer and the seller. The customer gets the best deal and the seller is always on the lookout for technological advancement which ranks their company at the top. There are innumerable web hosting companies in India which is giving healthy competition to one another. This is especially good for business organizations that are on the lookout for the same. Linux server is very popular among business community. Linux Hosting India offers affordable, reliable and superior support in this field.

Linux

Linux is an open source operating system based on the model of UNIX operating system. Linux is a leading server operating system. It can be installed in a wide range of computer hardware’s, mobile phones, video game consoles to mainframe and super computers. Linux is very cheap when compared to windows. In the case of web hosting servers Linux is an obvious preference due to its stability and durable approach.

Linux Server Hosting

Before hiring a company for hosting service, there is an important thing that you need to consider. The scripting language used in your website is the first thing that you need to consider. If your website is using languages like PHP, MySQL or Pearl, you must go for Linux server hosting. Linux Hosting India offers web hosting on Linux platform. Linux is basically an open source software product and thus is not bound by any high licensing fees. Thus it can be freely downloaded from the website.

Linux server can be easily converted into a windows server. But the same cannot be said about windows as it is very complicated. Linux is an operating system which is very much adaptive and flexible. Businesses run in a vibrant environment and many changes has to be made time and again. Linux is modifiable. You can make changes according to your requirements. The programmers and expert staff of Linux Hosting India provide state of the art service in web hosting.

One of the plus points of Linux server is that it is capable of handling large volumes of traffic to the website. It is also capable of hosting multiple sites. With Linux Hosting India customization can be done in real time. Linux works with some of the most popular scripting languages like PHP, MySQL and Pearl. Linux web hosting is the most economical form of hosting your website. The host or owner has to only bear the cost of distribution. Linux hosting is deemed to be the most secure form of web hosting. Linux gives us innumerable advantages when compared to other platforms used for web hosting. It provides compatibility, stability, security and very easy Linux conversion process.

The Concept of Limits in a Linux System

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Every UNIX based system like Linux has a certain set of limitations on the kind of feature sets and resources that can be used by a program or user. This can range from simplistic models like the complete length of file’s path, to the kind of arguments and calls that a program can have.

Since these limits effectively reduce the scope and abilities of a program, an application trying to be portable across different UNIX implementations needs to account for varying limit standards. The Single UNIX Specification’s third version (SuSv3, in short) defined three discrete functions that an application could call to determine the limits of the system it was working on – fpathconf(), pathconf() andsysconf(). It also defined a limit range that a UNIX implementation could enforce. The most crucial part of this set range was a minimum limit. This particular limit would be set as a constant in the limits header file, with a name that begun with the _posix_ string. If an application could stick to the specified minimum limits, it would manage to be portable across most implementations in all likelihood. However, that would result in a loss of functionality that higher limit values would bring in. This made determining the limits of a system using sysconf() etc. particularly invariable. This function was also a great tool to determine runtime invariant and increasable values.

A function like pathconf(), on the other hand, deals with the name of file paths. Limits on these pathnames could be determined using functions like fpathconf() and pathconf(). Limits can also be ascertained through shell commands. The getconfcommand can help you determine the limits in the UNIX implementation you are currently working on.

During runtime, sysconf() can tell you the limits you need when you specify the name of the limit in the function’s argument. If the limit cannot be determined, or there is an error of any sort, the function will return a value of –1′. SuSv3 dictates that the value returned by the function has to be constant all through the calling.

The difference between pathconf() and fpathconf() is the method of specifying the file/directory. In the case of the former, the pathname needs to be specified, while for the latter, a previously opened file descriptor is required. SuSv3 does not require these functions to return values than remain constant all through an entire process runtime. This lets a file system to be mounted and dismounted multiple times, all while the process is running.

Indeterminate limits are ones that are not defined by an implementation limit constant. The functions stated above would end up returning –1′ to indicate the indeterminacy of the limits required. These hindrances can be handled in a number of ways – the most practical of them being to avoid the checking of limits, and instead perform the corresponding library function calls. If those calls fail too, the errnomust be checked to judge whether some other system limit was violated, so that you can modify the program behavior accordingly.

You should avoid hardcoding system limit assumptions into your programs, as it may not be valid across every file system or UNIX implementation. Using the necessary functions, SuSv3 can guide you to make your program adapt even in real-time.

Linux Based Products Linux Web Hosting

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Since its inception in the early 60s, a number of computers have been running on Linux operating system. However, since its launch numerous advances had to be made before it became serious competition for Windows and several other hosting servers. Since a few years, offsite Linux web hosting has been much more readily accessible. Products based on Linux have been gaining immense popularity since a few years.

Linux hosting is basically a type of web hosting where the server software namely Php, Mysql etc is installed on open source Linux operating system. What this means is that the software and all the updates are completely free of cost. The best thing about Linux is its flexibility and capability to work across all platforms; you can use it in any way you want. In simple terms, Linux is to operating systems what .pdf formatting is to document control.

Despite the fact that Linux for desktop computers and notebooks’ is still somewhat unusual, there are several genuine tech savvy users out there in the market who have learned long ago that Linux eradicates a lot of of the problems that Windows users have grumbled about for numerous years. On the other hand, Linux based products have turned into one of the best business standards over the past decades and numerous businesses have incorporated Linux operating systems into their systems and used Linux servers almost entirely.

One of the foremost features of Linux is its ability to work across all platforms. Moreover, when we speak about Linux hosting, a company that proffers Linux compatibility has most likely at some point shifted from UNIX or still includes UNIX in its offerings. Numerous analysts have stated that Linux is in reality the result of high performance operating system standards that created its footing initially in the mid 1980s.

Furthermore, as with any kind of compatibility problem, any business using Linux will be required to source out and reference check a hosting company that is capable to grant not only Linux servers , but can also supply the ideal technical support which Linux based products require. Additionally, the hosting company should also provide sufficient backup that is obligatory in order to accomplish Linux mission which is proper server hosting.

Hence, make sure that if you want to use Linux based products you should select the best hosting company which is compatible with Linux. Meanwhile, for the masses, Linux itself may be the most appropriate operating system. However, its intrinsic requirement for a support organization to learn yet one more operating system factually inside and out is a bit wobbly at best.

So in order to trust your Linux files to an offsite Linux web hosting company makes sure their technical support group has been properly licensed in the particulars of Linux’s use. Linux hosting platforms are extremely speedy and don’t have any lagging problems. With Linux, quick change of details or a database change is likely very possible.

When you are using a Linux hosting company you will observe that there is no limit on the disk space that you consume. Hence, for all of you who have multiple pages, the unlimited disk space feature is quiet handy. There is also no limit on the amount of broadband that is used, this makes your website very fast and you automatically gain an edge over your rivals. Linux hosting also offers limitless SSH access. In simple terms, SSH is a secured network protocol that permits you to send files or network commands to the server through a secure line. For all those looking for a web hosting solution, Linux is a great choice.

Ways To Monitor The Linux Dedicated Servers

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Virtual server is the server which doesnt exist by physical manner. Still it will do all the functions of the real server. The virtual server hosting virtual servers to provide most efficient load balancing by acting like a single IP address for several clients and uses address translation to send the tasks to the real server to handle. Hereafter we will see how we are going to monitor private services and attributes of Linux dedicated servers.

The main attributes and services need to be monitor is CPU load, memory usage, disk usage, logged in users and running processes in the Linux Dedicated Servers. There are available some public services by the Linux dedicated servers they are the HTTP, FTP, SSH etc.

The following ways to monitor the Linux dedicated servers is based on out installation of nagios in our system as a monitoring tool. There are available a lot of ways to monitor the attributes and remote located servers of Linux/ UNIX. One of the main way is by using the SSH key and by the check_by_ssh plug-in to execute on the remote servers. This will be of very useful when we are monitoring hundred of thousands of system which is having a very high load.

Another important method of the Linux and UNIX remote servers using NRPE add-on. NRPE allow executing the remote plug-in on remote Linux and UNIX servers. This method is useful to manage internal resources like disk usage, memory usage etc on the remote host in the Linux dedicated servers.

The top ten Linux hosting websites are justhost.com, ipage, myhosting.com, immotion, dream host.com hub, arvixe, host cator, cirtex hosting, go daddy.com. Every provider is having advantages and disadvantages; they allow the companies to host their website using Linux operating system. When it comes to budget based servers. Because small start up companies cant afford to the windows based servers since we have to pay for all the software packages are of only by cost.

All the Linux software packages are free of cost and hence to make a linx operating server is simple when compared to the windows operating system.

The third party tools play an important role in monitoring and maintaining the dedicated servers. The important function of these monitoring tools is to check the safe level of certain parameters. CPU utilization, server RAM, physical temperature of the server is its various components, bandwidth usage and disk space usage. Here are the various third party tools to do this task. These tools can be installed on the web server and may appear as additional components in the c Panel or Plex site administration dashboard of your web server. The graphical design of the website traffic can be seen through the software package called as webalizer. As an IT manager you should know exact state of your server if incase it is a dedicated servers. Virtual Private Server Hosting.