Subject: Re: your mail
To: Jonathan Stone <jonathan@DSG.Stanford.EDU>
From: Brian Hechinger <wonko@blackhole.arkham.net>
List: port-i386
Date: 06/20/1997 17:46:16
Jonathan Stone drunkenly mumbled...
> 
> That depends on your kernel config file.  

joy. :)

> If you take a GENERIC-style kernel, drive numbers are allocated
> sequentially by the autoconfig code.  it would be sdNa, where N is the
> number of drives on your first controller.

i'm not so sure i like that.  being the person i am i want to be able to look
at the device name and be able to tell exactly where something is, not just
guess.

> If you use a wired-down config, you get whatever you wired down.  You
> could wire each (controller, unitnumber) pair to a specific unique
> drive number; or if you have few enough drives that you can give them
> all unique unit numbers, you can wire down a SCSI unit number to a
> drive number, regardless of which controller it's on.

ok.

> Wiring down sd? drive numbers has the nice side-effect that if a drive
> dies, or loses power, or gets moved, the device number of other drives
> doens't change, and so you don't start mounting drives on mountpoints
> at random, using partition numbners in fstab that assume the drive is
> still there.

this is (IMHO) a Bad Thing (TM)  

> Maybe we should put examples of this in a sample config file,
> or in the documentation, or something...

again, IMHO, i think we should do away with sdNa where we just add to the
end of the list.  very very very bad things will happen because of that if
i remove a drive from my first controller.  (imagine the havoc it would
create with ccd volumes!!!

-brian

-- 
** Brian Hechinger ** wonko@mail.arkham.net ** http://www.arkham.net **
--
"Yes, evil comes in many forms, whether it be a man-eating cow or
 Joseph Stalin, but you can't let the package hide the pudding!  Evil
 is just plain bad!  You don't cotton to it.  You gotta smack it in the
 nose with the rolled-up newspaper of goodness!  Bad dog!  Bad dog!"
                                --The Tick