atacontrol and creating raid-1 arrays

[Søren Schmidt]

Eirik Øverby wrote:
> Hi,
> 
> I have just done a 'cp /dev/ad4 /dev/ad6'. Those drives should be 100% 
> identical (even the same drive models). Will the command
> 'atacontrol create RAID1 ad4 ad6' ruin the data on my drives?
> 
> I ask because I am hoping to avoid the need for another 150 gigs of 
> space just to copy the data off of the drives before creating the array...

"depends"

Since the RAID metadata has to be put on disk it wont work if you have 
that area used for real data. Depending on what controller you use the 
metadata can be stored in different places. Other than that it works if 
you are *sure* the disks are identical (dd with a decnet blocksize is 
*much* faster tha cp).

-Søren