[nylug-talk] Disk imaging/cloning - sorry if someone asked this already

[Ward Griffiths]

On Thursday 01 May 2003 10:41 am, Mordy Ovits wrote:
> On Thursday 01 May 2003 10:34 am, Peter C. Norton wrote:
> > > Quick note to the unwary:  Don't do that while $DISK is mounted
> >
> > As long as there's not much activity, it'll still work as a
> > quick+dirty.  You'll just have to fsck after you first re-image.
>
> *shudder*.  That would terrify me.  Skewing the dd over time changes is a
> bad idea.  It's a gamble I wouldn't take, even if it would work most of the
> time.
>
> > However, this leads to an interesting question: is there a way to
> > mount an image as a disk - not just as partitions - then mount parts
> > of the image as partitions.
> >
> > I.e. something like:
> >
> > mount -o dev=bigloop disk_image
> > mount -t ext2 /dev/bigloop/0 /mnt/root
> > mount -t ext2 /dev/bigloop/1 /mnt/root/boot
> > mount -t ext2 /dev/bigloop/2 /mnt/root/usr
>
> The partition splitting code doesn't run on loopback devices, but it could
> be made to be, somehow.  Good answer, eh? :-)

Then folks will be using the partitions inside loopback filesystems as their 
own modifiable items, and then loopback those and then things recurse to 
Hell.  Let's try and leave it at only one or two removes from reality.  As 
Poor Richard said, "Three removes equal one fire" (Franklin was talking about 
posessions and physical change of residence, but I feel he had a point that's 
still valid a couple of centuries later).
-- 
Ward Griffiths					wdg3rd at comcast.net

A culture with any genuine self-confidence would not lie awake at night
fretting that Mr. Smith down the street might not fully "support" the
cause of the moment or might fail to love the president. It ought to be
enough that Smith, however outraged he may be at the course of events,
refrains from appearing in arms to oppose it.  
He might not be a good "citizen" in that respect, but he could well be a
damned good neighbor.       		           Joseph R. Stromberg