


              NOVELL TECHNICAL INFORMATION DOCUMENT

TITLE:              Stacker Initialization and Configuration
DOCUMENT ID:        014921
DOCUMENT REVISION:  A
DATE:               24FEB94
ALERT STATUS:       Yellow
INFORMATION TYPE:   Issue
README FOR:         NA

NOVELL PRODUCT and VERSION:
Novell DOS 7

ABSTRACT:

This document explains the use of the Stacker data compression
utility.

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NOVELL.  NOVELL MAKES EVERY EFFORT WITHIN ITS MEANS TO VERIFY
THIS INFORMATION.  HOWEVER, THE INFORMATION PROVIDED IN THIS
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OR IMPLIED CLAIMS TO THE VALIDITY OF THIS INFORMATION.
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ISSUE

     This document is not designed to be an introduction to the
     Stacker portion of Novell DOS 7.  Users who are new to
     Stacker should read the following references before reading
     this document:

     Novell DOS 7 User Guide: Chapter 12 "Disk Compression"
     Novell DOS 7 README.TXT
     Stacker section in the DOSBOOK online reference manual (Type
     DOSBOOK STACKER at the command line.)

     INITIALIZATION

     The Novell DOS 7 Stacker Disk Compression is the most
     sophisticated compression technology included as part of a
     Disk Operating System (DOS).  One of Stacker's benefits is
     that its device driver, STACKER.BIN, is loaded as part of
     the DOS Kernel.  This feature allows the Novell DOS 7
     compression to be transparent to the user.  In Novell DOS 7,
     compressed drives are loaded before CONFIG.SYS file which
     reduces the need for configuration editing.
     STACKER.BIN

     The STACKER.BIN file is the Novell DOS 7 compression device
     driver.  The STACKER.BIN file is created by the SETUP
     program during the process of compressing your first
     partition or removable media.  After being created, the
     STACKER.BIN file must remain in the root directory of the
     host or boot drive and should be marked with the read-only,
     system, and hidden attributes.


     Upon bootup, the STACKER.BIN file will be loaded as part of
     the DOS kernel after IBMDOS.COM.  After it is loaded into
     conventional memory, the STACKER.BIN file references a file
     called STACKER.INI for information on how to configure your
     system and load your compressed drives.

     STACKER.INI

     The STACKER.INI file is STACKER.BIN file's information and
     configuration file.  The STACKER.INI file contains
     configuration settings ranging from the compression tuning
     used by the STACKER.BIN file to the actual location of each
     of the compressed drives (STACVOL files).  The STACKER.INI
     file is created when you compress your first partition or
     removable media.  The STACKER.INI file must also remain in
     the root directory of the host or boot drive and should be
     marked with the read-only, system, and hidden attributes.  A
     STACKER.INI file might look similar to the following:

          /P=1
          /I-
          /DIR=C:\NWDOS
          /F=128
          C:\STACVOL.DSK, RP

     Each line in the STACKER.INI file performs an individual
     function.  Compressed drive letters are assigned in the
     order that their respective STACVOL.xxx files are listed in
     the STACKER.INI file.

     The following is an explanation of the contents that may
     appear in the STACKER.INI file.  Examples of each of these
     switches will be provided in a subsequent section of this
     document.

     *         The asterisk is used in the STACKER.INI file to
               reserve a drive letter.  For example, if a user
               has two compressed partitions and decides to
               uncompress one, Stacker will insert an asterisk
               (*), in the STACKER.INI file at the same position
               that the previously compressed partition occupied.
               This is done to preserve the order in which drive
               letters appeared before uncompressing a partition.

     /BD=x     This switch is used to specify the letter of your
               first Stacker drive (beginning drive letter).  For
               example, Stacker will put this switch in the
               STACKER.INI file if a DoubleSpace drive is
               converted to a Stacker drive.  This is done to
               maintain the same drive letter for the Stacker
               drive that was used previously by the DoubleSpace
               drive.

     /DIR=     This switch specifies the directory for the
               overlays used by the Stacker utilities included in
               Novell DOS 7.  This will preclude finding the
               wrong overlays in retail versions of Stacker.

     /F        This switch controls the size of the array on
               diskette container files.


     /I-       This switch prohibits Stacker from intercepting
               Stacker specific commands.  The retail version of
               Stacker installs its own equivalents of DOS
               commands, such as DIR, which are written
               specifically to work with Stacker.  The /I- switch
               is included in the STACKER.INI file because the
               Novell DOS 7 commands such as DIR and CHKDSK have
               been written to work on Stacker drives. 
               Therefore, Stacker does not need to intercept
               these commands and run its own equivalents.

     /P=n      This switch sets Stacker's compression tuning. 
               Compression tuning is represented by a value
               ranging from 0 to 9.

     /P=0      This switch turns compression tuning off, which
               decreases the memory that Stacker uses by 4.4 KB,
               and it is the fastest speed setting for Stacker.

     /P=9      This switch is the slowest speed setting for
               Stacker; however, it allows for the best
               compression of files.  SETUP allows you to choose
               from three compression tuning options:

               (/P=1 default) Fastest speed and standard
                              compression
               (/P=5)         More compression and a bit less
                              speed
               (/P=9)         Best compression, least speed

     /Q-       This switch forces Stacker to display the Stacker
               drives and their associated uncompressed drives
               during bootup.

     /RP=n     This switch sets the amount of removable disk that
               may be loaded along with the drive normally
               recognized by the computer (such as A and B).  As
               an example, Stacker will recommend adding this
               switch before compressing a RAM drive that was
               created using the VDISK.EXE file.  This is because
               RAM drives are treated similarly to removable
               disks by Stacker.

     DISK MOUNTING

     A line similar to the following will appear in the
     STACKER.INI file for each compressed drive on the system:

               C:\STACVOL.DSK,SW

     In this example, the C:\ represents the drive letter where
     the Stacker drive (which is actually a large file) resides
     before being loaded.  STACVOL.DSK is the name of the Stacker
     drive or file.  Finally, SW is the Stacker drive's mounting
     parameter.  The following is a list of drive mounting
     parameters:

     SW        Swap.     This parameter tells STACKER.BIN to load
                         the Stacker drive as the next available
                         drive letter.  After the Stacker drive
                         is loaded its drive letter is replaced

                         with the original drive letter
                         (uncompressed drive) where the
                         STACVOL.xxx file was.  This option is
                         the default for partitions that had
                         their data entirely compressed by
                         Stacker in SETUP.

     NS        No swap.  This parameter tells STACKER.BIN to load
                         the Stacker drive as the next available
                         drive letter.  This option is the
                         default for compressed drives created
                         from free space.

     RP        Replace.  This parameter instructs the STACKER.BIN
                         file to load the Stacker drive as the
                         same drive letter that contained the
                         STACVOL.xxx file.  This option is the
                         default for compressed removable media
                         and RAM Disks.


     EXAMPLE:  Loading of a Single Stacker Drive

     The system has two floppy diskette drives (A and B) and one
     hard disk with one partition (C).  The C: drive is the only
     drive that has been compressed with Stacker.

     /P=1                ;fastest speed and standard compression
     /I-                 ;turn off Stacker interceptor
     /BD=F               ;Stacker drive letter that contains
                         ;STACVOL file will appear as F
     /DIR=C:\NWDOS       ;Location of Stacker utilities' overlays
     C:\STACVOL.DSK,SW   ;C was compressed and contains the
                         STACVOL
                         ;file before being loaded

     After this STACKER.INI file is processed by the STACKER.BIN
     file, the example system's drives will be as follows:

     A    Floppy Diskette drive
     B    Floppy Diskette drive
     C    Stacker compressed drive
     F    Uncompressed partition containing STACVOL file for
          Stacker compressed C: drive

     EXAMPLE: Loading of a Single Stacker Removable Drive

     The system has one floppy diskette drive (A) and one hard
     disk partitioned into one partition (C).

     /P=9                ;best compression
     /I-                 ;turn off Stacker interceptor
     A:\STACVOL.DSK,RP   ;A is an automount Stacker removable
                         drive

     After this STACKER.INI file is processed, the example
     system's drives will be as follows:

     A    Automounting Stacker drive
     C    Uncompressed partition


     Note:     Drives are recognized as automount removable
               drives after a removable drive has been
               compressed.  From then on, each time a removable
               is inserted in the automount drive, it will be
               checked for a STACVOL file.  If a STACVOL file is
               found it will be mounted as a compressed drive
               occupying the same drive letter as before.

     EXAMPLE: Loading of Multiple Stacker Drives

     The system has two floppy diskette drives (A and B) and a
     hard disk partitioned into four partitions (C through F). 
     The C: drive is uncompressed.  The D: drive is entirely
     compressed with Stacker.  The E: drive was compressed at one
     time; however, the user has used UNSTACK to uncompress it. 
     The F: drive's free space is compressed.

     /P=5                     ;more compression and a bit less
                              speed
     /I-                      ;turn off Stacker interceptor
     D:\STACVOL.DSK,SW        ;D was compressed and contains the
                              ;STACVOL file before loading
     A:\STACVOL.DSK,RP        ;A is an automount Stacker\
                              ;removable drive
     REM E:\STACVOL.DSK,SW    ;E was compressed but now is
                              ;uncompressed
     *                        ;inserted to retain the drive
                              ;letter
                              ;used by E: previously
     F:\STACVOL.000,NS        ;F's free space was compressed

     After this STACKER.INI file has processed, the example
     system's drives will be as follows:

     A    Automounting Stacker drive
     B    Floppy diskette drive
     C    Uncompressed boot partition
     D    Stacker compressed drive
     E    Uncompressed partition (was Stacker drive at one time)
     F    Uncompressed partition containing STACVOL file for
          Stacker compressed I: drive
     G    Uncompressed partition containing STACVOL file for
          Stacker compressed D: drive
     H    Reserved drive letter for previously compressed Stacker
          E: drive
     I    Stacker compressed drive (created from free space)

     STACHIGH.SYS

     As mentioned earlier, the STACKER.BIN file is loaded in
     conventional memory by the DOS kernel.  The STACHIGH.SYS
     file may be loaded in the CONFIG.SYS file after a memory
     manager to move STACKER.BIN into upper or DPMS memory. 
     Examples of each of these configurations follows:

     1.   Loading the STACKER.BIN File into Upper Memory

               DEVICEHIGH=C:\NWDOS\EMM386.EXE /F=NONE
               DEVICEHIGH=C:\NWDOS\STACHIGH.SYS


          This option will load approximately 42 KB of the
          STACKER.BIN file into upper memory, which leaves only a
          small portion of the device driver in conventional
          memory (approximately 2 to 3 KB).

     2.   Loading the STACKER.BIN File into DPMS Memory

               DEVICEHIGH=C:\NWDOS\EMM386.EXE /F=NONE
               DEVICEHIGH=C:=NWDOS\DPMS.EXE
               DEVICEHIGH=C:\NWDOS\STACHIGH.SYS

          This option will load approximately 41 KB of the
          STACKER.BIN file into extended memory, which leaves
          only a small portion of the device driver in
          conventional memory (approximately 3 to 4 KB).  This
          option is the more beneficial of the two options,
          because conventional and upper memory are virtually
          unaffected.

     SUMMARY

     If you have Stacked any of your drives, your boot drive
     should contain at least the following files:

     IBMBIO.COM     Hidden file
     IBMDOS.COM     Hidden file
     NWDOS          Subdirectory
     STACKER.INI    Hidden file
     STACKER.BIN    Hidden file
     STACKER.LOG    Text file listing any exceptions that
                    occurred during the Stacking process.
     STACVOL.DSK    Hidden file.  This is the container file for
                    your stacked drive.

     If your C: drive is compressed, your boot drive will be your
     D: drive.

