25 Apr
2006
25 Apr
'06
7:33 p.m.
Michael B. Brutman wrote:
That was my initial thought, that I must be missing something - but I guess
the original poster is trying to copy across non-identical drives, with
filesystems containing data which addresses the disk by something other than
linear blocks. I'm betting then that a raw copy wouldn't work because the
target drive's geometry is totally different.
To identical drives, *or* when the copied data is a filesystem that addresses
by linear block from the start of the filesystem, I can't see any reason why
dd won't work.
cheers
Jules
My first
experiment was with linux where I created a PC linux
boot CD and hooked my two drives up planning to just dd from
one drive's raw device to the other. To my amazement, I discovered
that linux does not have a raw disk I/O capability by default.
I tried using the block devices, but the resulting copy was
not intact. After doing a bit of searching, I discovered that
there is some sort of rawio extension which allows a raw device
to be associated with a block device, but it also said that dd
would not work with this raw device due to buffer alignment
issues vs. DMA. Go figure...
I missed something here .. why didn't dd work for you?