A wide variety of failures can result in loss of
data, and recoveries of those files become an
imperative task to let any enterprise continue
functioning. File recovery is the salvaging process,
where the lost data in files, failed, wrecked or
inaccessible storages, mainly primary storages, such
as the disk system, and different other storage
media, are retrieved through special software. The
situation generally arises out of physical damage to
the storage device or in the event of any logical
failures in the file system, which makes these media
normally inaccessible. There is ofcourse that
misconception that file recovery may also pertain to
recovery of data which have been deleted.
Storage media, such as, CDs, Tapes, hard disks,
etc., can go through many types of physical damage,
which causes data or file damages. There could be
partial or complete data losses. This may be due to
many factors of physical damage and mechanical
failures, with crashing of the head of a disk and
failed motors, tapes which simply breaks away, etc.
In such mechanical damages, there is bound to be
some data or file losses and in lots of cases the
logical structures of the files may be damaged as
well.
The usual physical damage that occurs in our
system cannot be rectified by the end users. Taking
out a disk system from a computer need an expert
handling, as otherwise dust settling of the surface
can inevitably damage the platters, resulting in
complications in the recovery process. In most of
the cases, users do not have the technical expertise
required to handle hardware failures and therefore,
such specialists are required to handle the
situation more than often. In order to do such
repairs, you will need to have specified
environmental conditions, viz., use Class 100 clean
room facilities, in order to protect your hardware
sub-assemblies from environmental damage, while
repairs are being carried out. Such repairs would
perhaps require a kind of data or file recovery
software, where, generally the raw image is
extracted from the storage media, transforming it to
usable data using reconstruction process. This is
done after successful repair of the physical damage
of the concerned storage media.
The most known logical damage of a storage system
occurs from power fluctuations or outages, where the
file system structure is not completely written in
the storage medium. In the same manner, especially
the failures of controller system, such as RAID
(Redundant Arrays of Inexpensive Disks) controllers
contribute to such grave failures. Logical failures
leave the files in an inconsistent state, causing
various kinds of problems, for example, infinitely
re-cursing directories, drives reporting negative
amounts of free space, system crashes with actual
loss of data, etc. In modern operating systems,
there is some sort of software tool to enable repair
these sorts of failures, by correcting the
inconsistencies in their native file systems. With
Linux we find the fsck utility, Mac OS X has a disk
utility and Windows provides the de-fragmentation
and chkdsk facilities. Though the de-fragmentation
found in today's Windows operating systems, such as,
Windows XP Professional are much like the one
offered by Norton, it appears that Norton has a more
comprehensive software for de-fragmentation process.
There are ofcourse third party utilities available,
such as, The Coroners Toolkit and The Sleuth.
Internet search also reveals free download of such
utilities, claiming to be the ones which can take
care of file recovery procedures.
There are file recovery software which would
recover lost and deleted files, which may have been
lost due to corruption in a mass storage media, may
be due to loss in format or other means, like,
virus, or trojan infection. These may lead to system
shut down and total software failure. These
utilities may be termed as 'self service file
recovery system', and may be considered to be an
alternative to the deployment of professional data
recovery services, if such failures are not too
grave. Most of the software work on disk image
creation, creating image files applying different
compression method. Other do-it-yourself software
vendors claim that as long as the hardware is
operational, any failed file system can be
recovered, even recovering data lost due to failed
RAID system.
There are free downloads of such data or file
recovery software available from the internet
sources. These tools have quite substantial features
in recovering your lost data, so long as the
hardware has not been physically damaged, as for
example the physical damages of prime storage
systems, as discussed in the earlier part of this
article. If that is the case, you still have a
chance to recover your lost data with these free or
inexpensive data recovery software utilities. Free
data recovery utilities are seldom available, which
really do the job as they claim, and before
installing these free software tools, reviews, if
available, should ideally be looked into.
There are two important aspects to be considered
with data or file recovery. If your data is valuable
and used in mission critical applications, you
should not be concerned with freeware. If you should
try one, try the ones which do not require
installation in your computer system. But it is
recommended that in cases of failures in critical
environments, you should seek the help of data
recovery service agents, who are professionally
equipped and experienced in such disaster recovery
scenario. If you should decide to go in for freeware
or shareware applications try to use the ones which
do not require installation. Instead the software
should run out of a CD, a Flash Drive or a second
drive that you might have. If not, you may face a
situation where all your data could get permanently
over-written.
I am a post graduate in Computer Science and
have been working as the profit center head of an
international organisation. I look after 15 to 18
Oracle database projects in Europe.
As a hobby I have been writing for the last
10+ years on various subjet matters. I have
expertise in project report preparations,
preparations of technical tutoring documents,
presentation preparations, writing of technical
articles, technical documentations abstructs of
various books, copy writing, reviews, articles,
proof reading, news papers, magazines,presentations,
including SEO articles, etc., and also contributed
in writing press releases and various profiles. I
have been writing for over 10 years. I have good
experience in writing papers, including
transcriptions on various topics with extensive
research on the subject. I have also participated as
a freelancer in online sales and marketing. All my
works are quality orginals. I am generally involved
with few but large continued assignments in writing
technical & non-technical articles.
prabirsenuk@yahoo.co.uk
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