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Re: Using dd to clone smaller drive to larger drive

hi ya brian

On Tue, 6 Dec 2005, Brian C wrote:

> Warning to archive readers. I believe a typo in one of the commands 
> below will destroy your data. Read on...

more serious than typo .. :-)
> Alvin Oga wrote:
> [snip]
> > - if you want to leave bad data behind
> > 
> > mount /dev/hdb1 /mnt/new-disk
> > 	tar cvfp old-disk-paritions /mnt/new-disk

definitely .. don't type the above "psuedo cmd"

all that will happen, if typed as is, is a big ole error
message and nothing harmful if that above was typed

but it was a typo as you pointed out .. thanx
	- typo is missing "|" and corresponding extracting tar

it was meant as:

	tar cfp - old-disk-partitions | ( cd /mnt/new-disk ; tar xvfp - )

	- i mixed syntax for my tarcp alias in the prev 1st posted cmd
	called "tarcp"  ( shorthand is good for some things )

	"old-disk-partitions"  is things like /bin /var /usr /opt

	/mnt/new-disk is exactly that, a newly formated and mounted disk

> I interpreted it to mean type:
> 	tar cvfp /dev/hda3 /mnt/new-disk/var

that can be one interpretation ... BUT, that is what was previously posted

you CANNOT use "tar" to copy a whole "partition" ( /dev/hda3 )
tar should have been bitching at you ???? 

and at a minimum, your tar cmd will copy "whatever is
the list of files"  ( /mnt/new-disk/var ) into your device /dev/hda3 
per your tar command

	/dev/hda3 might go blank or tar might bitch about no data
	to copy or that it's a "cowardly command" ( no data to write )

have fun 

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