Installation problem

Manolis Kiagias sonicy at
Tue Jul 31 05:37:35 UTC 2007

Joel Hatton wrote:
> On Mon, 30 Jul 2007 21:46:44 -0700, Garrett Cooper wrote:
>> Rakhesh is correct.
>>    SATA / PATA drives show up under ad[m]s[n][l], where m is the disk 
>> number (zero based), n is the slice, aka partition number in the non-BSD 
>> (/Solaris?) world, number (zero based), and l is the respective letter 
>> for the partition (it can vary depending on the purpose, a being root, b 
>> slice, c all of the disk, [d-j?], other values / relevances.
>>    SCSI / SAS is almost exactly the same. The only difference is 'ad' 
>> is replace with 'da'.
> There is a difference between SATA and PATA in one respect (and I'm sure
> I'll be corrected by a developer if my experience is unique). PATA drives
> appear to be allocated ad0-3, SATA drives begin above that. So, ad4 can
> (and may in this case) be the first and only fixed disk in the system.
> This was certainly the case with my last SATA system.
> cheers,
> joel
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It may have to do with how the SATA controller is setup in the bios. In
some cases there is something like an "emulation" mode where the SATA
controller actually replaces the PATA one rather than augmenting it. In
these case you may get an ad0 for the first SATA drive. If you are
running SATA in native mode, the first drive is ad4. I have two machines
with single SATA drives and they both show ad4 disk names.

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