Re: [gentoo-user] dd'ing small drive to large one

[Alex Schuster <wonko@wonkology.org>]

Iain Buchanan writes:

> On Mon, 2011-01-31 at 22:19 +0100, Alex Schuster wrote:
> > Now I'm really really sure there will be no problem. What I wrote above
> > about the gemotry is true I think, but all modern drives seem to have
> > 255 heads and 63 sectors per track, so they will be compatible.
> > 
> > 	Wonko
> 
> The only problem I see with dd is that it won't do any error checking,
> afaik.  Will you have the old drive in as #2 later to double check?

No, there's no space in this damn Dell desktop PC. If there were, we would 
just install the 2nd drive, and I would copy all stuff from remote. And then 
change grub so it boots from the 2nd drive. This would be a little 
unelegant, as I would copy the root partition while in use, but there should 
not be too much data that would change while I do this - probably not any 
data at all. For the /var partition, this would be different, but in 
practice this would probably work well either. Still, I would use the LVM 
snapshot feature for this.

But I never head a problem with dd. Do you mean read errors due to bad 
blocks? Then I should at least find something about this in the syslog. I 
could use dd-rescue though.
Or is it about other, undetected errors? Isn't there some CRC checksum by 
which ensure that would be detected? Or does dd not care about this?

> The other option is clonezilla.  It will be a bit more work for you, but
> you can script it to clone the partitions / drives / copy boot loaders
> and so on.  Then the remote assistant can just boot it (from usb key
> even) and press go!

Clonezilla sure looks interesting. I even has LVM support, so this probably 
could be done. Still, using only dd seems simpler to me, and more foolproof. 
But I'll check it out anyway. Thanks for the pointer.

	Wonko