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cc: current@freebsd.org
Subject: Re: atacontrol and creating raid-1 arrays
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Eirik =D8verby wrote:
> Hi,
>=20
> 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?
>=20
> I ask because I am hoping to avoid the need for another 150 gigs of=20
> space just to copy the data off of the drives before creating the array=
=2E..

"depends"

Since the RAID metadata has to be put on disk it wont work if you have=20
that area used for real data. Depending on what controller you use the=20
metadata can be stored in different places. Other than that it works if=20
you are *sure* the disks are identical (dd with a decnet blocksize is=20
*much* faster tha cp).

-S=F8ren