Subject: None
To: Brian Hechinger <wonko@blackhole.arkham.net>
From: Jonathan Stone <jonathan@DSG.Stanford.EDU>
List: current-users
Date: 06/20/1997 14:37:15
wonko@blackhole.arkham.net (Brian Hechinger) writes:

>what does a second SCSI host look like under NetBSD??  if sd0a is root on SCSI
>ID 0 and sd1a is root for SCSI ID 1 what would the root of SCSI ID 0 on a
>second SCSI host look like?

That depends on your kernel config file.  

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.

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.

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.

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