Cheryl Thompson writes:
> There is a way to see if hardware compression is enabled by using the
> support license installation program.  The command is SUPLICEN (you must
> be logged on as Manager.Sys.  You will also need to call HP and get
> either a temporary two day password or they will fax you a letter to
> fill out and you can get a two year license.  It's  probably easier to
> use devctrl and set it to either enable or disable.

Well, by using SYSDIAG SCSIDDS *after* you've entered your diagnostics
password via SUPLICEN.PUB.SYS.

Here's what I get on my 5.5 machine's DDS-2 drive.  Note that the "DCE - Data
Compression Enable" line seems to reflect what you've set via :DEVCTRL.

:sysdiag

*****************************************************************
******                                                     ******
******               ONLINE DIAGNOSTIC SYSTEM              ******
******                                                     ******
******          (C) Copyright Hewlett Packard Co.          ******
******               1987, 1989, 1990, 1992, 1994          ******
******                 All Rights Reserved                 ******
******                                                     ******
******              DUI Version A.02.25                    ******
******         Diagnostic Monitor Version   A.02.29        ******
******                                                     ******
*****************************************************************

    Type "HELP" for assistance.

DUI >run scsidds ldev=8 sc=50
***************************************************************************
******                                                               ******
******                    SCSI DDS DIAGNOSTIC                        ******
******                                                               ******
******         (C) Copyright Hewlett-Packard Co 1990-1996            ******
******                    All Rights Reserved                        ******
******                                                               ******
******  This program may only be used by HP support personnel and    ******
******  those customers with the appropriate Class license or        ******
******  Node license for systems specified by the license.  HP       ******
******  shall not be liable for any damages resulting from misuse    ******
******  or unauthorized use of this program.  This program           ******
******  remains the property of HP.                                  ******
******                                                               ******
******                      Version  A.02.33                         ******
******                                                               ******
***************************************************************************


Welcome, Today is MON, APR 19, 1999 at  2:00 PM

##########################################################################
#                            W A R N I N G                               #
#                                                                        #
#           DO NOT ABORT THIS DIAGNOSTIC WHILE IT IS RUNNING.            #
#           AN ABORT MAY CAUSE THE SYSTEM TO HANG.                       #
##########################################################################


   SCSIDDS Diagnostic initializing -- Please wait . . . .

   Section 50 -- INTERACTIVE EXTERNAL EXERCISER

   Checking if tape loaded in drive....
                                   .... No Tape loaded



   SCSIDDS>modesense


   Which page to be displayed?
       0 -- All Supported pages
       1 -- Disconnect-Reconnect Page
       2 -- Device Configuration Parameters
       3 -- Medium Partition Parameters
       4 -- Data Compression Mode Page
       5 -- No Pages

   Your selection [0]>4


       =============================================================
                               MODE SENSE DATA
       =============================================================


RAW DATA :
--------
Byte Count = 28

               0   1   2   3   4   5   6   7   8   9
              --  --  --  --  --  --  --  --  --  --
Byte    0     1B  00  10  08  24  00  00  00  00  00
Byte   10     00  00  0F  0E  C0  80  00  00  00  20
Byte   20     00  00  00  00  00  00  00  00


INTERPRETED DATA :
----------------
Sense Data Length = 27 (number of bytes of MODE SENSE data)
Media Type = 0
     Only one media type is supported.
Write Protected Bit = 0
     The tape is write-enabled.
Buffered Mode = 1
     Buffered Mode.  The drive reports GOOD status on WRITE commands
     as soon as the data record has been transferred to the buffer.
Speed = 0
     The dds only supports one speed.  The default speed.
Block Descriptor Length = 8
Density Code = 36
     Hewlett-Packard/Sony DDS-2 Format
Number of Records = 0
     All the remaining logical records on the tape will have the
     medium characteristics specified by the block descriptor, or until
     a subsequent MODE SELECT changes those parameters.
Record Length = 0 (length in bytes of each logical record)
    -----------------------------------------------------------------
     PAGE CODE DATA:
Page Saveable Bit = 0
     There is no non-volatile RAM on the drive into which parameter
     data may be saved.
Page Code = 15 [ Data Compression Mode Page ]

Additional Length = 14 (number of remaining bytes in this page)
DCE - Data Compression Enable           = 1
DCC - Data Compression Capable          = 1
DDE - Data Decompression Enable         = 1
RED - Report Exception on Decompression = 0
Compression Algorithm                   = 32
Decompression Algorithm                 = 0


   SCSIDDS>exit


   End of section 50 -- INTERACTIVE EXTERNAL EXERCISER



   End of pass number 1



SCSIDDS Exiting...
SCSIDDS has terminated
DUI >exit

END OF PROGRAM
:
--
Mark Bixby                      E-mail: [log in to unmask]
Coast Community College Dist.   Web: http://www.cccd.edu/~markb/
District Information Services   1370 Adams Ave, Costa Mesa, CA, USA 92626-5429
Technical Support               Voice: +1 714 438-4647
"You can tune a file system, but you can't tune a fish." - tunefs(1M)