Installation problem

Rolf G Nielsen lazlar at
Tue Jul 31 06:18:41 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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If there are PATA channels on the motherboard (which there are on most 
motherboards, I believe) they're most likely the primary and secondary 
ATA channels, making the SATA channels the third and above. If you have 
the ATA_STATIC_ID option in the kernel, the SATA drives will then show 
up ad ad4 and above, whether or not there are any PATA drives connected. 
With the ATA_STATIC_ID option the primary master is ad0, primary slave 
is ad1 and so on, whether or not there are any drives connected. If you 
remove the ATA_STATIC_ID option, the ATA drives (PATA and SATA) will be 
assigned the lowest number not in use, so with no PATA drives connected, 
the first SATA drive will be ad0, the second one will be ad1 and so on.

This is my experience, but I'm not a developer, so there may be some 
twists that I've missed, and if so, I'm sure someone will correct me. :)


Vänligen / Sincerly,
Rolf Nielsen

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