What is Linux

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Linux – the operating system for a GNU (pronounced Gnew) generation. It has been dubbed the alternative to Microsoft, the solution to all life’s problems and many other things that may or may not be true. Bu what is Linux, and should you care?

To answer the first question, it’s a free operating system that looks and acts very much like Unix. You can download it off the Net for free, or you can copy it legally from a friend – although this might take all the fun out of using that CD-Writer you’ve got and never use for anything, except to brag about it to your friends.

Alternatively, you can buy it nicely packaged from an Internet store and get it delivered with a book about Linux, (Linux Unleashed).

Distributors charge not for the operating system itself, but for their time in packaging and presenting it. Two popular flavors of Linux are Free BSD and Ubuntu. These offer the same basic systems with a few slight differences that can lead to long and entertaining godly wars between supporters of each.

If you’re getting into Linux for the first time, Ubuntu is a good bet. You can either go for Ubuntu Desktop which comes with a GUI, or you can opt for Ubuntu Server if you planning to host websites of your own. The server edition has no GUI, but you can install KDE or Gnome to make your life easier. Most of your configuration will be done via the Terminal and you will have to learn a lot of Linux commands.

Linux is more complicated, and it depends on the kind of person you are. If you’re the type of computer user who wants every application to run straight out of the box and your system to just do what it’s told and run your games, then stick with Windows. But if you’re a pioneering soul who wants to find out more about your system and tweak it to perform to the max, then Linux is definitely worth a try.

If you want rock-solid Internet access, if you want to support the development of free software and more efficient solutions, or if you’re just the type of person who needs control over every aspect of your life including how your machine performs, then you’re definitely a Linux candidate. Linux is perfectly suited to students, developers and just about anyone who wants to try something other than the norm. Newcomers will find support straight off the Internet from thousands of kindred spirits.

It’s worth a try – maybe you’ll discover a Whole New World of fun and adventure. Or maybe you’ll just take it straight off your machine and go back to Windows. However, if you planning to try it out, then load it on that old machine that’s just lying around in the basement. You don’t need powerful processors and hardware – the most important component is memory. If you have 512mb and a 20gig hard drive then you should be OK. You should be able to run all your applications including your websites with ease. Remember, you will need a permanent connection to the Internet if you going to host your own websites. The best part is that you don’t need any antivirus and antispyware software if you’re running Linux. Every would-be-virus-writer out there has only one target in mind – Microsoft Windows.

Whether you stick with Linux or not, you’ll have come out of your safety zone and taken a trip to the cutting edge of computer technology.

Resolving Root inode is not a directory. Clear Linux Error

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In Linux operating system, you can check the integrity of file system and hard drive. This command resolves majority of issues with hard drive and file system, avoiding need of Linux Data Recovery. This command-line utility runs in five phases. In first phase, it checks data blocks and their size, in second phase, it checks for path names. In the following phases, connectivity, references counts, and the cylinder groups are examined respectively. If the fsck fails in second phase, situations can be very drastic.

The fsck may fail in the second phase due to iNode issues. In a practical scenario, you may come across the below error message while checking integrity and consistency of your system through fsck utility:

-Root inode is not a directory. Clear?-

After this error message, you can not access your Linux hard drive and encounter serious data loss situations. In order to gain access of your valuable data in such circumstances, you need to find out the cause of this problem and perform Data recovery linux by sorting it out.

Grounds of the issue:

This problem occurs after corruption to the root iNode. The corruption might be caused by improper system shutdown, virus infection, system crash, and more.

In Linux file system, iNode is a data structure that holds all the critical information of files and directories, except their names and contents. It is a unique number, assigned to every file/directory. Every file/directory has an individual iNode. The file/directory is accessed through iNode only.

In the particular situation, the root iNode of Linux system is damaged. It is generally the second iNode. Root iNode is first iNode to file system and it represents starting point or root of file system.

If you select ‘Yes’ in above error message, it will remove parent entry of every iNode from root directory. In third phase of the fsck utility, root iNode is tried to recover, but you encounter further error if the process fails:

-Cannot Allocate Root Inode-

In such critical situations, Linux Data Recovery is required to extract lost data. The recovery is best possible using Linux Recovery software, which perform absolute recovery in the majority of data loss situations. With read-only conduct and simple graphical user interface, the applications are completely safe and easy to use.

Stellar Phoenix Linux Data Recovery is the most advanced application to recover lost, missing, and inaccessible Linux data. It recovers from Ext4, Ext3, Ext2, FAT12, FAT16, and FAT32. The software is designed for all distributions of Linux operating system including SUSE, Debian, Red Hat, and Fedora.

How to Fix Unable to resolve UUID Error in Linux

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Modern distributions of Linux operating systems use UUID (Universally Unique Identifier) to uniquely identify hard drive or other data storage devices, in place of the conventional block names like /dev/sdb and /dev/hda1. It is due to the fact that UUID is never modified, even if the hard drive is switched. It is stable as compared to traditional methods, and prevents system failure and need of Linux Data Recovery solutions.

UUID is a 128-bit string that is used for making the Linux hard disk management simple. If you look at /etc/fstab file in your Linux computer, you find the entry in the following format, in place of the familiar hard drive designation:

UUID=62fa5eac-3df4-448d-a576-916dd5b432f2

In comparison to the traditional hard drive identification techniques, UUID is quite easy and reliable. For instance, in the traditional Linux systems, when you try to insert a new hard drive in a system that already has two hard drives, the drive is inserted between existing drives. At this point, ‘mount’ command attempts to mount the newly inserted drives as home.

In such situation, you need to log on as a single user for resolving the problem. However, when you log on, it gives you some error message and in the worst case scenario, you may encounter kernel panic. You can fix this issue using UUID.

UUID creates a unique entry for each hard disk volume in the Linux file system tree. Using UUID offers easy management of your Linux hard disks and creates less complication while adding or removing the disk.

Although, UUID is quite useful and it provides various advanced features, but it also has some faults. Sometimes, you may encounter the below error message when you attempt to access a UUID based Linux hard drive:

-Fsck 1.40.8 (13-Mar-200 fsck.ext3: Unable to resolve ‘UUID=d8533154-cef1-4cce-a823-9f3f74aab65b’-

After the above error message, you can not access the particular hard drive. All the data stored on your hard drive become inaccessible and you come across critical data loss. At this point, Linux Recovery Software come for your rescue.

The applications perform absolute Data recovery linux in most of the logical data loss situations, using advanced scanning algorithms. These tools enable you to perform Linux Recovery on your own as they have self-descriptive and simple graphical user interface. With read-only and non-destructive behavior, the applications are completely safe to use.

Stellar Phoenix Linux Data Recovery is the most comprehensive application for perfect recovery of all lost data. The software is compatible with all Linux distributions including SUSE, Debian, Red Hat, and Fedora. It recovers lost data from Ext4, Ext3, Ext2, FAT32, FAT16, and FAT12 file system volumes.

Process Timers in Linux Operating System

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Clocks and timers have been a part of UNIX systems from their very inception. Standard UNIX (POSIX.1) has three clocks. One tells the time and is directly accessible to the user. The other two have other purposes, which don’t often concern the application programmer. There are 2 types of timers: one shot timers and repeating ones. The former only expires once and is used to signal a special event that needs to occur only once. Repeating timers go off at regular intervals and are used to schedule periodic events.

There is, basically, only one clock which application programs use in Linux. The operating system keeps track of current date and time by storing the number of seconds that have elapsed since, midnight January 1, 1970 UTC. This period is also called an epoch. This date is considered as the informal -birthday’ of the UNIX operating system. The time is stored in a signed long integer. The time function can be used to know how much time in seconds has elapsed since the start of the epoch. The prototype for time call is: #include time_t time (time_t) *tloc);

In all versions of UNIX the time() system call may be used to obtain the time of the day. This call is peculiar in that if given the address of a long integer as an argument, it places the time in that integer and returns it. If, however, a null pointer is passed, the time of day is just returned. The time_t is convenient for calculating differences between times, but difficult to print dates. Several routines are available to convert the long integer returned by time() into an ASCII date string. With the UNIX operating system, an ASCII date string is a string as shown below: Day Mon dd hh: mm : ss yyyy

The ctime() library function can be used to do the above conversion. Its prototype is:

#include Char *ctime (const time_t *clock) Example: #include #include Int main () { long now, time (); struct tm *today, *localtime (); time ( today=localtime ( printf (-today is: %d/%d/%d \n-, today->tm_mon + 1, today->tm_mday, today->tm_year); exit(0); }

This time function measures real time or wall clock time. In a multiprogramming environment, we may be more interested in the amount of time an individual process uses. This is called virtual time. The system call tiems returns information about the execution times of a process and its children. One shot timers: the most common example of these kind of timers would be the sleep call. #include Unsigned sleep(unsigned seconds);

When a process executes sleep it blocks for the number of seconds specified. The sleep function can be used as a sort of crude interval timer. Standard UNIX timers: the standard UNIX interval timers defined in the Berkeley and SR4(1170) versions of UNIX are as follows – ITIMER_REAL ITIMER_VIRTUAL ITIMER_PROF

POSIX Interval timers: the 1170 specification timers do not provide sufficient flexibility to deal with real time tasks. To be useful in real-time environments, we need more than just three timers. There needs to a greater time resolution and allowance for determining timer overruns.

All in all, UNIX timers can be used to find out the CPU time requirements of a program for benchmarking. Interval timers are also extremely important to allow scheduled tasking.

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Linux Data Recovery Software to Bring Your Precious Linux Data Back

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These days, many users are switching their operating systems from Windows to Linux. Even, some are opting for a dual boot system by installing Linux alongside Windows to use a bit closely before completely migrating to Linux. The reason is pretty simple. Linux is new and with various new features. Apart from this, the operating system is undoubtedly the most frequently updated operating system than that of its other counterparts. But, one thing is quite true that no operating system is entirely free from any loose holes. Moreover, if it is not right to term it as loose hole, still, there are instances when the OS failed to match with the user expectations. Among such troubled occasions, Linux data recovery applications can be immensely useful in recovering your valuable data back.

You may encounter a number of instances of data loss in your Linux system. The reason can be a simple data deletion to harsh system crash. Some of the mostly encountered Linux data loss situations are listed as below:

1) Accidental/intentional deletion

2) Accidentally formatting the hard drive while resolving some Linux disk error

3) Re-installation of the operating system by formatting the drive or volume

4) File system corruption

5) Operating system malfunction

6) Any software/hardware contradiction resulting in the the crashing of the Linux system

Under any of the above situation, your valuable data from the Linux drive or volume either gets lost or becomes inaccessible. Still, you can restore the data back, if you have taken any backup of your data recently. If there is no recent backup available or the restoration process results any error, you need to look for some other Data recovery Linux methods.

One soothing fact about data loss is that unless the data in the drive is overwritten by some other piece of data, it never gets lost permanently. So, if you can take strict care of the troubled Linux drive or volume against any case of overwriting, all your seemingly lost data can be definitely retrieved by running any software etc.

These Linux Data Recovery utilities have powerful algorithms to dig into the hard drive and recover the data efficiently. All the features of these recovery applications are read-only in nature and you need not have to worry about the safety of your data.