backups & cloning

Warren Block wblock at
Wed Sep 30 03:27:41 UTC 2009

On Wed, 30 Sep 2009, Polytropon wrote:

> Forgot to mention this:
> On Tue, 29 Sep 2009 22:23:00 -0400, PJ <af.gourmet at> wrote:
>> 1. will the s1a slice dump the entire system, that is, the a, d, e, f
>> and g slices or is it partitions?
> The ad0s1 slice (containing the a, d, e, f and g partitions) can
> be copied 1:1 with dd. By using dump + restore, the partitions
> need to be copied after another. In each case, the entire system
> will be copied. For this purpose, even the long lasting
> 	# dd if=/dev/ad0 of=/dev/da0 bs=1m

This copies everything on the disk, including sectors not used by a 
filesystem.  So it usually takes a while.

> 	# dd if=/dev/ad0 of=/dev/da0 bs=512 count=1

Not necessary, the first block was already copied, well, first.

-Warren Block * Rapid City, South Dakota USA

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