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Linux and Unix Data Recovery

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http://linux.bihlman.com – Linux and Unix Data Recovery By Nahar Dijla Forty years ago there was only one type of computer system. Today, the variety of computer systems has grown into its own world of complexities. Technological advances have been extraordinary in the hardware side of the industry. Yet while we marvel at ever-faster storage devices and greater processing power, it’s good to remind ourselves that we also need amazing new operating systems and file systems to manage the hardware and data. True, there are many machines using Microsoft file systems, but it is a widely accepted fact that UNIX file systems survived stronger and much longer. UNIX operating systems have definitely established itself as a stable environment for most companies. In fact, most of the servers that are part of the infrastructure of the Internet are running a variant of the UNIX operating system. Recently, Linux has proved to be a stable alternative for companies running database servers or other business applications. The Linux operating system placed great emphasis and focus towards the server environment, and increasingly the environment that is crucial to every professional, namely the desktop environment. Linux remained constant and been true to its UNIX roots. No wonder, it continues to grow by virtue of its ‘Open-Source’ status. The good thing about being Open-Source is that no single company gets to control the operating system. Some of the smartest minds in computer science established and devoted their careers to developing the operating system and file systems for the UNIX and Linux platforms. Before the Seventies, the custom designed operating system was meant for for the hardware of the machine. The UNIX operating system had been designed in the late Sixties and was implemented in the early Seventies. The amazing thing about UNIX was that it allowed hardware companies to concentrate design efforts on hardware without having to design a custom operating system to go with it. When UNIX started out, it wasn’t even marketed as a new operating system yet UNIX emerged further as an operating system and a strong alternative to mainframes. With great focus on the file system point of view, UNIX brought a number of improvements to the design of file systems. Most professionals for data recovery focus on the evaluation and recovery of one of these types of file systems. The stages of recovery are partition and volume verification, logical file system scan, error investigation, and repair, and volume reports. However, there are situations where the quality of the recovery cannot be verified. One of these situations is when a file system repair utility has made permanent changes to the file system. When the tools of professionals fail to undo these changes because specific data has been changed, it is a difficult situation. Most of the UNIX file system variants also permanently remove inode entries when data is deleted. Situations where files have been overwritten present the same problem; specific information that points to the data has been overwritten. All is not lost in circumstances like this. There are professional data recover engineers who have tools that will bypass the file system and look for specific file types – sometimes known as the magic number or unique identifier of a file. In these cases, the file names may be unrecoverable, however the file data may be readable. No doubt, data recovery is a science-a great, emerging discipline that requires the best of trained experts. By opting for a company that claims to specialize in data recovery yet uses off-the-shelf recovery tools doesn’t guarantee efficient data recovery success. You must opt for a company or a professional that researches and studies these file systems and then designs a suite of tools to facilitate Linux and Unix data recovery. Remember, automated tools provided by several data recovery companies don’t provide a good answer to complete the data recovery process/ This requires the professional services of experienced data recovery engineers who work till data is recovered. So remember to opt for the best solution providers so that quality is never compromised. Data Recovery RAID Data Recovery (General)