In order to allow MEDIA to be partially self configured, choose Semi automatic from the Configure menu. The window shown below will appear.

If Do or Return is entered a window with the query "Are you sure you want to auto configure? ([EXIT] or [CTRL] [Z] to abort)" will appear. If [DO] or [RETURN] is pressed, the form shown below will appear.

You may list up to 10 types in this form and add any available device. Enter [F17] next to the device name that you want to add and [F18] next to any types you want to delete.

The MEDIA SERVER process is a detached process which coordinates certain activities for the MEDIA Librarian. The server process is controlled by various parameter settings. The interactive interface to the server is entered by using one of the commands below:

$ RUN MEDIA_LIBRARY:MEDIAS_VAX (or _AXP) MEDIAS> SHOW DEVICES $ MEDIAS :== $MEDIA_LIBRARY:MEDIAS_VAX (or _AXP) $ MEDIAS SHOW DEVICES

The OPERATOR privilege is required to use this facility.

The server process is the file MEDIA_LIBRARY:MEDIAS.EXE. This process is started during the system boot by the command procedure SYS$MANAGER:MEDIA_STARTUP.COM. The server uses a data file MEDIA_LIBRARY:MEDIAS.DAT to coordinate and share data across a cluster. It is important that this file is placed in the common cluster directory. A log file is kept containing a list of all server events. This file is SYS$MANAGER:MEDIAS.LOG. This log file will contain a listing of any error messages generated while trying to submit jobs.

6.1 Tasks performed

There are several specific tasks performed by the server process. They are:

• Log all removable drive activity
• Assist in volume validation
• Control drive allocation
• Monitor drive/volume error activity

6.1.1 Log all activity

• Allocations
• Mounts
• Dismounts
• Deallocations

One of the objects of the MEDIA Librarian is to minimize the number of REPLY commands the OPERATOR is required to issue. The main way this is achieved is to leave all media on-line when the job completes rather than unloading.

This requires that a subsequent job has a reliable way of determining what was left on-line by a previous job. The server process monitors and tracks all volume identifications as they are mounted and dismounted. This information is then supplied to each MEDIA job as requested. If a situation arises (due to label or mount characteristics) where it is uncertain whether the on-line volume is the correct one, the volume is unloaded and the OPERATOR is requested to mount the right one.

6.1.3 Control of drive allocation

In many instances, it is important to be able to control who and for what a drive (tape drive or disk drive) is allocated. On an open system with little security requirements, this is an easy way to force all the users to use the MEDIA Librarian System. When this feature is enabled (via the LOCK_DEVICES parameter), all devices defined to the MEDIA Librarian are allocated to the server process at boot time. Then they are only released on a proper request from a medium job (either interactive or batch). This implies that the user must have cataloged (either temporarily or permanently) a medium that is of the proper type. This in turn will prevent an allocation from taking place for a medium to which a user has no access.

The OPERATOR can interactively mark a device as unavailable by using the interactive server interface. A typical command to do this is:

$ MEDIAS SET/DEVICE DBA1:/UNAVAILABLE

All user allocations that are approved by the server process will initiate a watch dog process that will transfer control back to the server process whenever the device is released by the user. The release can either be accidentally (by an abort) or via a normal MEDIA DEALLOCATE command.

6.1.4 Error monitoring

The server process monitors all device error reports and updates the error counter in the media database. An error counter is kept for each medium cataloged into the system. Whenever a cataloged volume is on a drive, a record is kept of the number of device errors recorded by ERRFMT process. When the medium is dismounted, the corresponding error counter is incremented.

6.1.5 Parameter file

The parameter file is read by the SERVER program and the MEDIA program and controls their behavior. If any changes are made in the parameter file, it is necessary to restart the server process.

6.2 Log file

The generated log file contains all messages generated by the server process. All error conditions will also be sent to the operator. Certain types of error messages can be generated while the server is attempting to submit jobs. For example, an invalid medium name. If you have some errors, this file and/or the operator log is the place to look for a listing of all error messages. A typical log file generated by the server program is listed below:

+++++++++++++++++++++++++++++++++++++++++++++++ MEDIA Server activated on 12-OCT-1996 13:55:55.50 ----------------------------------------------- MEDIAS V4.0.0 VAX/VMS V5.0 ISE, Inc. Licensed to ISE, Inc. Created on 10-FEB-1996 11:00 For CPU 1 S/N:DR00139 SID:20447371 ----------------------------------------------- =========== 12-MAR-1996 15:49:49.25 =========== Allocated MTA1:, media 1400, for MOSSBERG2(BATCH_769) =========== 12-MAR-1996 15:50:07.26 =========== Dismounted _MTA1:, media 1400, for MOSSBERG2(BATCH_769) =========== 12-MAR-1996 15:50:07.30 =========== Deallocated _MTA1:, media 1400, for MOSSBERG2(BATCH_769) =========== 12-MAR-1996 16:39:05.49 =========== Allocated MTA1:, media X191, for ANDERSON(ANDERSON) =========== 12-MAR-1996 17:01:05.39 =========== Deallocated MTA1:, media X191, for ANDERSON(Unknown) =========== 12-MAR-1996 17:17:18.87 =========== Allocated MTA1:, media X190, for ANDERSON(ANDERSON) =========== 12-MAR-1996 17:19:04.90 =========== Mounted _MTA1:, media X190, for ANDERSON(ANDERSON) =========== 12-MAR-1996 17:34:04.90 =========== Dismounted _MTA1:, media X190, for ANDERSON(ANDERSON) =========== 12-MAR-1996 17:34:04.93 =========== Deallocated _MTA1:, media X190, for ANDERSON(ANDERSON) =========== 12-MAR-1996 17:38:32.73 =========== Allocated MTA1:, media 1200, for MOSSBERG2(MOSSBERG2) =========== 12-MAR-1996 17:39:01.84 =========== Mounted _MTA1:, media 1200, for MOSSBERG2(MOSSBERG2) =========== 12-MAR-1996 17:39:47.84 =========== Dismounted _MTA1:, media 1200, for MOSSBERG2(MOSSBERG2) =========== 12-MAR-1996 17:39:47.87 =========== Deallocated _MTA1:, media 1200, for MOSSBERG2(MOSSBERG2) =========== 12-MAR-1996 17:40:06.38 =========== Allocated MTA1:, media SANAVI, for SANAVI(SANAVI) =========== 12-MAR-1996 18:07:32.88 =========== Deallocated MTA1:, media SANAVI, for SANAVI(Unknown) =========== 12-MAR-1996 23:00:00.10 =========== Schedule BACKUP_ALL_SS, job 797, entered on queue SYS$BATCH =========== 13-MAR-1996 06:00:10.23 =========== Schedule MORNING_JOB, job 798, entered on queue SYS$BATCH

This chapter describes the various commands that the server responds to.

7.1 Command descriptions

The available commands are listed below and then described in the following pages.

Command summary
EXIT	return to the system
HELP	provide on-line help
RESTART	restart the MEDIA_SERVER
SET	change internal settings
SHOW	display internal settings
START	start up a new server
STOP	stop the current MEDIA_SERVER

Exit back to the system.

The EXIT command (or [Ctrl] + [Z]) will cause the server to return back to the system. On exit any parameters that have been changed are written out to the parameter file. If a parameter has been changed a new server is created (same as the RESTART command).

Format

EXIT

Examples

 
 EXIT  or  [Ctrl] + [Z]
 
      

Provide on-line help.

The HELP command can be used to provide on-line help about all the various commands available to the MEDIAS program. The help command has exactly the same functionality as the VMS HELP command.

Format

HELP [command]

Examples

 
 HELP MODIFY 
 
      

Restart the server process.

The RESTART command will instruct the MEDIA_SERVER process to terminate and start up again. This is needed if a new version of the server has been installed or a parameter has been changed. This is performed automatically on exit after a SET/PARAMETER command has been used.

Format

RESTART

qualifier summary

Possible qualifiers:

/NEWLOG

Examples

 
 
 MEDIAS> RESTART/NEWLOG 
 
 
 
 
 
 
 
      

more

When the server restarts it is done in the context of the server itself. Thus all the process attributes (such as username, account, etc.) are retained and carried into the new process. All volume/device information is written out to disk and re-read on startup. A restart of the server thus has very little impact on any ongoing operations.

Qualifiers

/NEWLOG

The NEWLOG qualifier will cause a new log file (SYS$MANAGER:MEDIAS.LOG) to be created.

Set device or parameter attributes.

The SET command can be used to modify any of the parameters and the device availability.

Format

[SET/PARAMETER] parameter = "value"

or

[SET/PARAMETER] parameter == "value"

or

SET/DEVICE device [/qualifier]

qualifier summary

Type qualifiers:

/PARAMETER
/DEVICE

Device qualifiers:

/[UN]AVAILABLE
/[UN]LOCK
/RESET
/UNLOAD

Parameter qualifiers:

/NORESTART

Examples

   To make a device unavailable to the MEDIA system. 
 
 
  MEDIAS> SET/DEVICE MTA0:/UNAVAILABLE 
 
 
 
 
 
 
    This will prevent the server process from allocating this 
    drive to a user.  Be sure to make the device available 
    again at some later date. 
      

    To unload all devices and reset the internal SERVER 
    database. 
 
 
  MEDIAS> SET/DEVICE */UNLOAD/RESET 
 
 
 
 
 
 
    If a job is in progress this command will wait until 
    the job completes before doing the unload. 
 
 
      

more

All parameters that are changed are not implemented until you exit from the program or restart the server. When you do exit all the parameter files are update and the server restarted if needed. Parameters can appear in one of two files (MEDIA.VAR and MEDIA2.VAR). The MEDIA2 file is the cluster common and MEDIA is the node specific. The placement of the parameter is indicated by the number of equal signs. A single "=" indicates the MEDIA.VAR file, a double "==" indicates the MEDIA2.VAR file.

The SET/DEVICE command allocates the device for it's exclusive use, before unlocking it and making the setting changes. Thus if the drive is in use this command will wait for the current user to release the drive. If the device name is a logical name it is recursively translated before the set operation is performed.

Qualifiers

/PARAMETER

The parameter qualifier indicates that the SET operation is changing a parameter setting. This is the default type.

/DEVICE

The device qualifier indicates that the SET operation is changing a device attribute.

/RESET

The reset qualifier clears out any known information about what was last mounted on a drive. This can be useful if the medium has been physically removed from a drive and it is required that MEDIA not think it is still in place. Normally MEDIA will discover this on its own whenever another request comes along.

/AVAILABLE

/UNAVAILABLE

The available qualifier will mark a device as available or unavailable for allocation. This can remove a drive from use for service or other purposes. This does not prevent the drive from being used by other VMS programs. Only the MEDIA system will not allocate this drive in its normal operations.

/LOCK

/UNLOCK

The lock qualifier can force the server to lock or unlock the drive. This will temporarily undo the effect of the LOCK device attribute.

/NORESTART

The NORESTART qualifier suppress the default action of restarting the SERVER whenever a parameter is modified. For parameters that have no affect on the SERVER this qualifier can suppress the automatic restart.

/UNLOAD

The UNLOAD qualifier for an online drive, will trigger an unload sequence.

Display the server internal data.

The SHOW command displays all the various types of internal information maintained by the server to control all the various aspects of server operation.

Format

SHOW [/qualifier] [name]

qualifier summary

Possible qualifiers:

/PARAMETER [/SYMBOL=name]
/DEVICE
/VERSION
/SCHEDULING

Examples

 
    MEDIAS> SHOW/PARAMETER * 
    DEFAULT_TYPE = "TAPE" 
    DEVICE1 = device_bulletin 
    . 
    . 
      

 
    MEDIAS> SHOW/DEVICE * 
    MTA0:   tape,density=(800,1600),lock 
     volumes=2319(2319),2320(2320) 
     SMITH(0002CA), on ALPHA, at 10-JUN-1996 13:01:01.34 
 
    DBA1:   disk 
     not in use, on BETA 
     unavailable 
      

 
    MEDIAS> SHOW SCHEDULING 
    The BUSS node is currently scheduling 
      

more

The name can be a device or parameter name. Wildcards can be included.

Qualifiers

/DEVICE

The DEVICE qualifier indicates that the supplied name is a device name.

/PARAMETER

The PARAMETER qualifier indicates that the supplied name is a parameter.

/SYMBOL

The SYMBOL qualifier will redirect the parameter value into the designated DCL symbol. All the symbols are placed in the local symbol table. The default symbol name used if none is supplied is MEDIAS_RETURN.

/VERSION

The VERSION qualifier requests that the current version level of the program be displayed.