[rescue] Ultra1 oddity

[James Lockwood]

On Sun, 28 Apr 2002, Brian Hechinger wrote:

> besides, i think -r only configures what modules to load.  the cards are
> identified at every boot and given a sequential number in the order that they
> are found.

man path_to_inst:

...

     /etc/path_to_inst records mappings of physical device  names
     to instance numbers.

     The instance number of a device  is  encoded  in  its  minor
     number, and is the way that a device driver determines which
     of the possible devices that it may drive is referred to  by
     a given special file.

     In order to keep instance numbers persistent across reboots,
     the system records them in /etc/path_to_inst.

     This file is read only at  boot  time,  and  is  updated  by
     add_drv(1M) and drvconfig(1M).

...

     The  system  administrator  can  change  the  assignment  of
     instance  numbers  by editing this file and doing a reconfi-
     guration reboot. However, any changes made in this file will
     be  lost  if  add_drv(1M) or drvconfig(1M) is run before the
     system is rebooted.

Bottom line, when you have a device with an instance number, the first
time the driver binds itself to that instance it registers the entry in
/etc/path_to_inst.  This binding is maintained across reboots.  If you
want to delete the old hme binding, just remove the applicable line(s)
from /etc/path_to_inst.

This really does make the most sense.  Solaris can't tell the difference
between you moving an interface card and removing/installing one, so it
assumes that any card in a different slot should get a different instance
number.  This has saved my bacon more than once.  Making instances truly
dynamic and detected per reboot is IMHO far more dangerous.

-James