Browse Prior Art Database

Self Configuring Small Computer System Interface Device Driver

IP.com Disclosure Number: IPCOM000115054D
Original Publication Date: 1995-Mar-01
Included in the Prior Art Database: 2005-Mar-30
Document File: 8 page(s) / 257K

Publishing Venue

IBM

Related People

Forrer Jr, TR: AUTHOR [+3]

Abstract

Disclosed is a method for AIX* to automatically configure Small Computer System Interface (SCSI) Storage Devices on the RS/6000*. With this capability AIX releases and SCSI Storage Devices become independent of each other. The user no longer has to upgrade AIX to obtain support for a new storage device. Current computer systems provide several methods to configure new storage devices. They include the following: 1. The operating system has built in tables that contain data listing the attributes of the devices supported. As new devices are added to the system, the user selects the correct device type from a table or the system automatically configure the new device since it recognizes it and thus knows its configuration parameters.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 44% of the total text.

Self Configuring Small Computer System Interface Device Driver

      Disclosed is a method for AIX* to automatically configure Small
Computer System Interface (SCSI) Storage Devices on the RS/6000*.
With this capability AIX releases and SCSI Storage Devices become
independent of each other.  The user no longer has to upgrade AIX to
obtain support for a new storage device.  Current computer systems
provide several methods to configure new storage devices.  They
include the following:
  1.  The operating system has built in tables that contain data
       listing the attributes of the devices supported.  As new
devices
       are added to the system, the user selects the correct device
type
       from a table or the system automatically configure the new
device
       since it recognizes it and thus knows its configuration
       parameters.  The limitation of this approach is that devices
that
       are developed after the operating system is released are not
       supported.
  2.  The device supplier provides a diskette with the new device
which
       has to be loaded and a configuration program run before the
new
       device can be accessed.  This diskette either contains the
       required configuration data or the entire device driver,
       including the required configuration data.  The disadvantage
of
       this approach is that the user has to go through added steps
in
       order to get the new device operational.
  3.  The operating system provides a configuration utility that
       acquires, via a user interface, a series of questions about
the
       device in order to build the configuration data base for the
       specific device.  The disadvantage of this method is that the
       user has to be able to answer device specific questions.  The
       answers to these questions may not be available to the user.

      It would be desirable to provide a means to Plug and Play a
storage device on the RS/6000 using AIX.  That is, the user attaches
the new storage device to the system and then the operating system
gathers the necessary configuration data from the storage device and
then automatically configures the device without any user
intervention
required.

      The solution described here assumes that the storage devices
conform to the ANSI SCSI Specification.  (any level is applicable
although it is preferred that SCSI-2 and SCSI-3 devices be attached
for performance reasons).  When the operating system detects that the
device is not known, that is, the Inquiry Data Product ID field does
not match any product ID field contained in the PdAt configuration
data base, the operating system goes through the following sequence
in order to configure the device:
  1.  Issue an Inquiry Data SCSI Command to the device with the
EVPD=1
       and the Page Code=0.
      The drive...