Art wrote:
So, is it true that XXCOPY is useless for cloning the NT based
versions of Windows?
XXCOPY has never been written as a disk-cloning tool. Rather,
it is a general purpose file management tool that can do a lot
of things. One thing we chose not to do is to access the disk
using low-level device I/O operations. We want XXCOPY to be
a "well-behaved" application that uses only the standard file I/O
Win32 API functions in order to carry out the operations. This
makes XXCOPY safe and "device independent". As long as the system
has the infrastructure to provide a mechanism to access the volume
via the standard file I/O functions, XXCOPY can safely read from or
even write to the volume (including device types that XXCOPY has
never seen before). In other words, we want XXCOPY to be a safe
product. This is why XXCOPY can access files on a CD-R or DVD-R.
Or, if you install a "packet write" driver, XXCOPY can write
files on CD-RW, DVD-RW, etc. even though XXCOPY has no knowledge
of how files are physically stored in the media. Same things
with volumes in remote computer via network. All such activities
are plain old file I/O operations for XXCOPY.
Anyway, long story short, XXCOPY does not know how to access
the MBR, bootsector, etc. that are vital data structures in order
to make a disk bootable.
If you read the Technical Bulletin XXTB #10
http://www.xxcopy.com/xxcopy10.htm
you will find that XXCOPY cannot initialize a partition (you need
to use FDISK), format a volume (use FORMAT.COM), or make a partition
active. XXCOPY stays away from such activities that should be
handled by specialized tools. This way, XXCOPY can remain pure.
By not doing any low-level device I/O, we can claim XXCOPY is
very safe and would not corrupt a healthy volume (it can still
delete everything if you tell it do do so). In a NT dimly windows,
a regular application (such as XXCOPY) cannot access the system
registry files. This is probably the most problematic aspect
in trying to use XXCOPY to make a faithful clone of the system volume.
In other words, XXCOPY is a tool for IT professionals to perform
lots of file/directory management functions. Although XXCOPY can
create a bootable clone of Win9x/ME system volume, it was a by-product
of its design. Since Win NT/2K/XP systems do require a lot more work
than can be explained in a easy-to-follow article, we could not make
a similar article like XXTB #10 for Win XP. That's why we invented
XXCLONE.
Is XXCOPY useless to clone NT-based volumes?
Yes and no. XXCLONE can do a good job for this but the most ideal
backup regime may be achieved by a combination of XXCOPY and XXCLONE
when the requirement is more complicated. For example, one may use
the backup volume with additional directories that are not present
in the source volume. If you use XXCLONE, such extra directories
will be wiped out (in order to make a literal clone) because XXCLONE
does not have the "exclude" feature for its simplicity. Many
experienced users run XXCLONE to perform the essential operations
that cannot be done by XXCOPY and carry out everything else using
XXCOPY that is far more flexible than XXCLONE.
So, while XXCOPY cannot do the full cloning job all by itself
in NT-family Windows, it can play a vital role in customized backup
work.
Kan Yabumoto
