    AST RESEARCH, INC.             TECHNICAL BULLETIN # 0873A              7-1-94

                       MANHATTAN SMP AST EMPIRE MULTITHREADED SCO UNIX DRIVER

    PROBLEM:     When upgrading from the old AST Empire Multithreaded SCO UNIX
                 driver, release 1.0, (P/N 910727-038) to the new multithreaded
                 DAC960 UNIX driver (P/N 910727-321; see Software Bulletin #
                 0150), the following error is received during the installation
                 procedure:

                 Please insert the fd(60)sdac volume and press

                 sdac.sdac.Loading module
                 or 'q' to quit:
                 sdac.sdac.:Loading module fd(60) /sdac/driver/sdac/Driver.o  .text
                 ............
                 sdac.sdac.:Loading module fd(60) /sdac/driver/sdac/Driver.o  .data
                 ............
                 sdac.sdac.:Loading module fd(60) /sdac/driver/sdac/Space.o  .data
                 ............
                 fd(60) /sdac/driver/sdac/Driver.o : Symbol "scsi_distributed"
                 not found
                 sdac:Driver "sdac" not load.

                 Insert N2 (filesystem) floppy and press

    CAUSE:       AST's new Empire driver (P/N 910727-321) is incompatible with the
                 following releases of SCO’s operating systems:

                 SCO Open Server UNIX System 3.2 version 4.1 or lower.
                 SCO Open Server Network System 2.0.0 or lower.
                 SCO Open Server Enterprise System 2.0.0 or lower.

    SYSTEMS
    AFFECTED:        AST                                                 REVISION
                 PART NUMBER        DESCRIPTION                            LEVEL

                 520092-001      SMP 4-50 2/500 MB                          All
                 520155-001      SMP/P60 2/500 MB                           All
                 520092-001      SMP 4-50 2/500 MB                          All
                 520092-002      SMP 4-50 2/1.0 GB                          All
                 520001-001      SPARES KIT SMP                             All
                 520155-001      SMP/P60 2/500 MB                           All
                 520155-002      SMP/P60 2/1.0 GB                           All
                 520155-003      SMP/P60 2/2.0 GB                           All

    SOLUTION:    Use SCO Open Server UNIX System release 3.2, version 4.2 or
                 higher.
                 SCO Open Server Network System 3.0.0.
                 SCO Open Server Enterprise System 3.0.0.

    NOTE:        Because this driver is multithreaded, the "astctl" command can now
                 be used to distribute interrupt services across additional
                 processors.  Please review the documentation titled "AST
                 Manhattan SMP EFS for SCO UNIX 3.2v4.2 Release 1.1" (part number
                 001911-001) that comes with AST's Manhattan SMP for details.
                 This document is also included with release 1.1.0 of SCO EFS for
                 Manhattan SMP and is located in the Manhattan SMP section of
                 AST's BBS.  The file is called "SMP6.EXE".

                 The Empire driver is also located in the Manhattan SMP section of
                 AST's BBS and is available for download.  The file on the BBS is
                 called "SMP19.EXE".

                 Additionally, all of the disk subsystem statistics are now
                 available through the use of the "sar -d" UNIX command.