Subject: Re: Another changer, another changer problem
To: NetBSD-current Discussion List <current-users@netbsd.org>
From: Curt Sampson <cjs@portal.ca>
List: current-users
Date: 10/02/1998 21:32:49
On Sat, 3 Oct 1998, Greg A. Woods wrote:

> I'd kinda hoped there would be a predictable order, just as there is
> supposedly for NICs (i.e. the ethernet address sort order)....

Again, depends on the bus, as well as the particular NICs. 3com
cards on a P&P ISA bus attach in Ethernet address order (at least
if you're using 3com drivers). 3com cards on an ISA bus attach by
how the OS/driver decides to run through the port addresses.  3com
cards on PCI buses attach in bus and slot order.

> I really do like jumpers and switches (or hard-coded slot order or some
> other predictable physical identifier that's out of the meddling hands
> of the firmware and/or driver authors).

Well, a lot of people don't like that, and a lot of buses don't do
it.

> > Well, you Just Can't; see above.
> 
> Perhaps not on machines with ISA or PCI or other simplistic busses.

Well, that would cover a hell of a lot of the machines we run on,
if not all of them. What's the point of implementing your scheme
if it's useless on most machines?

> What does Digital Unix do?  That's one platform I know where the big
> monster servers have *many* busses and the potential for dozens, or
> hundreds, of similar controllers?

Same thing that NetBSD does.

cjs
--
Curt Sampson  <cjs@portal.ca>  604-257-9400    De gustibus, aut bene aut nihil.
Any opinions expressed are mine and mine alone.
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