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ACADMIN                             Aegis                              ACADMIN



NAME
     acadmin - autochanger administration

SYNOPSIS
     /etc/acadmin -[saielmcp] [-w n] [-h n] surface


DESCRIPTION
     Use acadmin to load and remove media, or to set and display the status of
     media in the HP Series 6300 Model 20GB/A Optical Disk Library System. Run
     acadmin directly on the the server node to which the autochanger (optical
     disk library) is attached; it will not work across a network.

     The autochanger has 32 slots in which to store media.  Each slot is
     specified in numeric order, by the surface number of the medium stored in
     that slot. Since each medium has two surfaces, the storage slot can be
     specified by two different numbers.  Therefore, surface represents both a
     storage slot and a medium's surface number.  Surface numbers range from 0
     to 63.   The following table shows how storage slots correspond to
     surface numbers.

                     Storage Slot Location    Surface Number

                             first                0 and 1
                            second                2 and 3
                             third                4 and 5
                              nth            2n - 2 and 2n - 1

     Use of this command may interfere with other access to the Optical Disk
     Library System.


OPTIONS
     You must be a node owner (see `node_data/node_owners) to use the -i, -e,
     -w, or -h options.  Any user may run the other options.

     -s        Start the autochanger.  This lets the device recalibrate itself
               and verify internal information.  You should use acadmin -s at
               least once after the node boots.  It is safe to use it after
               you mount the optical media.  Do not use -i or -e with this
               option.  If you specify surface, it is ignored.

     -a        Tests whether an autochanger is connected and active on the
               system. If the autochanger is present, acadmin prints a short
               string on the standard output file.  If the auotchanger is not
               present, acadmin does not generate any output. This option is
               useful in administrative and startup scripts.

     -i        Load an optical disk through the autochanger mailslot.  The
               optical disk must already be set into the mailslot for this
               option to work.  Do not use -s or -e with this option.  You
               must specify surface.  If the autochanger control panel
               configuration option 15 (Prevent Media Removal) is set ON,
               this option fails and returns an error message.

     -e        Eject an optical disk throught the autochanger mailslot.  You
               cannot eject a medium while either side is mounted or still in
               use by a program that directly accesses the disk surface (for
               example, salvol).  Do not use -s or -i with this option.  You
               must specify surface.  If the autochanger control panel
               configuration option 15 (Prevent Media Removal) is set ON,
               this option fails and returns an error message.

     -l        List the status of all media.  Using this option with -i, -e,
               -h, or -w displays the results after all the options take
               effect. Specifying surface with this option lists the status of
               only that medium.  If you specify surface, it is ignored.

     -m        List the local mount directory(s) of each mounted disk surface.
               Specifying surface with this option lists the mount directory
               of only that surface.

     -c        Suppress column headers and other formatting, thus making
               output easier to process with text-processing tools.  Use this
               option with -l and -m.

     -p        Test whether or not a surface is present in the autochanger.
               You must specify surface, a surface number for which to test.
               The surface is considered present whether it is in its storage
               slot, the picker, or a drive. If the surface is present,
               acadmin prints a short string on the standard output file.  If
               the surface is not present, acadmin does not generate any
               output. This is useful in an administrative script, such as a
               startup script, that mounts a surface if it is present.

     -w n      Set the "wait time" for surface to n seconds.  Omit surface to
               set the wait time for all surfaces to the same value.  The
               default wait time is two (2) seconds; the maximum is 32767
               seconds.  For more information, see the note on wait time and
               hog time, below.

     -h n      Set the "hog time" for surface to n seconds.  Omit surface to
               set the hog time for all surfaces to the same value.  The
               default hog time is 20 seconds and cannot not be less than the
               wait time; the maximum is 32767 seconds.  For more information,
               see the note on wait time and hog time, below.

     NOTE

     The Optical Disk Library System is similar to a "jukebox".  Data is
     stored on both sides of the media, but the drives read only one side at a
     time.  As you reference data, the autochanger may need to move media to
     and from storage slots, or it may need to flip a medium to get to data on
     the other side.  If you allow many users access to data on many different
     surfaces at one time, some users will have to wait until others finish
     using the drives.

     You may set two timing parameters to control sharing between users: the
     "wait time" and the "hog time".  These parameters control how often the
     media moves to and from the storage slots.

     The wait time specifies how long a surface will be left idle on one of
     the drives before other disk access requests force the disk out of the
     drive.  If there are no other access requests, the disk may remain in the
     drive indefinitely.  A short wait time may result in quicker service for
     requests to access other surfaces;  a long wait time may enable several
     short "bursts" of data requests for that surface (such as changing to and
     then listing the contents of a directory) to complete while the disk
     remains in the drive.

     The hog time specifies how long a busy surface may stay in a drive when
     there are other conflicting disk access requests.  If there are no other
     access requests, a surface may remain in the drive indefinitely.  After a
     surface has been in the drive for its hog time (even if the wait time has
     not expired), any other request for data access will force the disk to
     return to its storage slot and another disk is then loaded into the
     drive.  A long hog time causes other disk access requests to wait,
     thereby delaying delivery of that data to the user.  A short hog time may
     cause media to be exchanged too often.  Since it takes about 17 seconds
     for the autochanger to return one disk to storage and load another in a
     drive, a short hog time could force the autochanger to spend more time
     swapping media than accessing data.

     These parameters are your only controls over how the autochanger shares
     access among users with conflicting requests.  There are no priorities
     among surfaces of the media or among requests for IO service.  The wait
     time and the hog time apply to disk access requests from the server node
     and to disk access requests from the network; however, due to network
     queueing delays, local requests may take precedence over network
     requests.


EXAMPLES
     1.  List the status of all the media in the autochanger:

     $ /etc/acadmin -l

     mail slot EMPTY

     picker EMPTY

     drive 1 FULL - contains surfaces 0(up)/1
     drive 2 FULL - contains surfaces 2(up)/3

     storage slot for surfaces 0/1 EMPTY (in drive 1), wait=2/2, hog=20/20
     storage slot for surfaces 2/3 EMPTY (in drive 2), wait=2/2, hog=20/20
     storage slot for surfaces 4/5 FULL, wait=2/2, hog=20/20
     storage slot for surfaces 6/7 FULL, wait=2/2, hog=20/20
     storage slot for surfaces 8/9 FULL, wait=2/2, hog=20/20
     storage slot for surfaces 10/11 FULL, wait=2/2, hog=20/20
     storage slot for surfaces 12/13 FULL, wait=2/2, hog=20/20
     storage slot for surfaces 14/15 FULL, wait=2/2, hog=20/20
     storage slot for surfaces 16/17 FULL, wait=2/2, hog=20/20
     storage slot for surfaces 18/19 FULL, wait=2/2, hog=20/20
     storage slot for surfaces 20/21 FULL, wait=2/2, hog=20/20
     storage slot for surfaces 22/23 FULL, wait=2/2, hog=20/20
     storage slot for surfaces 24/25 FULL, wait=2/2, hog=20/20
     storage slot for surfaces 26/27 FULL, wait=2/2, hog=20/20
     storage slot for surfaces 28/29 FULL, wait=2/2, hog=20/20
     storage slot for surfaces 30/31 FULL, wait=2/2, hog=20/20
     storage slot for surfaces 32/33 FULL, wait=2/2, hog=20/20

     The output from this command line shows that both drives are full and
     surfaces 0 and 2 are facing the read/write heads in the drives, and that
     the wait and hog times are set to their default values on all the disk
     surfaces.

     2.  Set the wait time for surface 10 to 5 seconds and the hog time for
     surface 10 to 30 seconds; then list the status of the disk with surface
     10 and check if surface 10 is mounted.

     $ /etc/acadmin -ml -w 5 -h 30 10

     storage slot for surfaces 10/11 FULL, wait=5/2, hog=30/20

     surface  mount-point
     =======  ===========
      10      not mounted

     The output of this command shows that surface 10 has a wait time of 5 and
     a hog time of 30, while surface 11 retains the default wait and hog time
     setting.  This output also shows that surface 10 is not mounted.


SEE ALSO
     Information is available about related topics.  Refer to the following
     manpages or help files:

     netstat   For information about device statistics.

     netsvc    For information about increasing the number of network servers
               to improve network performance.

     mtvol     For information on mounting volumes.

     dmtvol    For information on dismounting volumes.

     lvolfs    For the amount of free space on each mounted volume.

Typewritten Software • bear@typewritten.org • Edmonds, WA 98026