Questions about the dd command

[Karl Larsen]

elmo wrote:
> I've spent literally hours trying to find direct answers on the dozens 
> of websites that discuss 'dd'
> but the couldn't find what I wanted.
>
> A few questions about the ' dd ' command:
>
>   For example:     sudo dd if=/dev/sda2 of=/dev/sdb2 bs=1440
>
>   1. Which is preferrable;    execute the command from an installed
>        ubuntu (/dev/sda2) or from a ubuntu CD?
>   
    There is no point to using dd from a CD-Rom. That is silly.


>   2. How do you  modify the example  to show the data as it is being 
> copied? 
>      Would this have a drastic effect on how long it takes to complete 
> the copy
>       compared to just watching a blinking cursor?
>   
    There is no way I know to see what is happening.
>   3.  What effect on the does the ' bs = ' number have on
>       the time to complete the copy or the accuracy of the copy?  Is 
> there a
>       default number if the the bs=    is omitted from the command?
>
> 	If you do not use a bs= it uses the default which is dead slow. I use bs=10000 and it is much quicker.
>   

    Suggest you read man dd where all these things come from.

Karl

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-- 

	Karl F. Larsen, AKA K5DI
	Linux User
	#450462   http://counter.li.org.
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