[geeks] Swapping Sparc boxes...

[Phil Stracchino]

On Thu, Dec 04, 2003 at 11:18:20AM -0500, Kurt Mosiejczuk wrote:
> You should be fine to just move the disk.  Things that COULD bite you
> is if your SCSI chain differs.  Linux's default device names for SCSI
> devices are brain damaged.  If you have another device before the ID
> of your boot drive (or any drive you depend on) Bad Things Happen.


Well, that depends on which device names you're using and whether you're
using devfsd.  With "classic" Linux device names, the first SCSI disk
found by the kernel is /dev/sda, the second is /dev/sdb, etc.  With
devfsd running, you can specify host, bus, target, lun just like you can
on Solaris.  I can address the third partition on my second disk as
/dev/sdb3, or as /dev/scsi/host0/bus0/target1/lun0/part3, or as
/dev/sd/c0b0t1u0p3.

The nice side to "classic" Linux device names is that you can take your
CDROM or your tape drive and change their SCSI IDs, move them to
different busses, even different controllers, and they remain /dev/cdrom
(or /dev/sr0, if you prefer to use that) and /dev/st0.  Likewise with
devfsd, move the CDROM to a different bus on a different controller and
even though it's now /dev/scsi/host2/bus0/target3/lun0 instead of
/dev/scsi/host1/bus1/target5/lun0, it's still /dev/cdroms/cdrom0.


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