How does CAM determine the order to number drives ?

Pete French petefrench at ticketswitch.com
Sun Aug 1 08:08:08 PDT 2004


> Wiring down the controller number doesn't usually affect drive ordering.
> All drives on all controllers are scanned at once in parallel, and the
> first to respond on any controller, regardless of the controller number,
> get to be da0.

Ah, thats interesting. It explains why my kernel config didnt work as I
had only wired down scbus0 and not the actual drive. Thanks.

*thinks*

But it does beg the question as to why my problem has gone away by moving
the slot the Adaotec controller is in. If all controllers are scanned in
parallel then the pysical positioning in the PCI slots should not make
any difference surely ? Yet it now seems to be booting reliably every time
with the ahc0 drive being found first.

-pcf. [even more puzzled!]


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