MPE/iX System Utilities Reference > Chapter 6 DISCUTIL

Operation

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You may invoke DISCUTIL only from the ISL> prompt. To display the ISL> prompt and start the utility, perform these steps:

Initiate a soft reset of the system by entering CTRL B.
At the CM> prompt, enter the following command to start the autoboot process:
```
  RS ENTER
```
When you see the message TO OVERRIDE, PRESS ANY KEY WITHIN 10 SECONDS, press RTN immediately.
When you see the message Interact with IPL (Y or N)?, enter Y. The system displays the ISL> prompt.
To start DISCUTIL, enter:
```
   
   ISL> DISCUTIL
```
The DISCUTIL banner will appear followed by the discutil> prompt.

NOTE: To see other utilities available before the system is started enter LS at the ISL> prompt.

DISCUTIL Commands

At the discutil> prompt, you may enter any of the following commands:

`CONFIGURE`	Configures additional devices. (The system console, all disks that were mounted at the time of the failure, and the tape drive are configured by default.)
`DISMOUNT`	Dismounts a disk volume making it inaccessible to `DISCUTIL`.
`DO`	Reexecutes a command in the command history stack.
`DSTAT`	Displays information about each mounted volume.
`EXIT`	Terminates `DISCUTIL` and reboots the system.
`HELP`	Lists available commands.
`LISTREDO`	Displays the command history stack.
`MOUNT`	Mounts a disk volume making it accessible to `DISCUTIL`.
`PDEV`	Lists the disks that are currently configured and mounted.
`REDO`	Modifies and reexecutes a command from the command history stack.
`SAVE`	Saves user-specified files from disks to tape.
`SHOWDEV`	Displays information about each configured device.
`TAPE`	Displays and selects the current tape `ldev`.
`UNCONFIG`	Unconfigures currently configured devices.

The remainder of this chapter describes each of the commands. Remember that these commands, though they may appear similar to MPE/iX commands or the commands used with other utilities, operate only as described here.

CONFIGURE

The CONFIGURE command is used to dynamically add or configure new/additional devices into the current configuration. You may access only configured devices with DISCUTIL.

NOTE: By default, DISCUTIL configures the system console, a tape drive, and all disks indicated as being mounted in MPE XL tables. For this reason, you need not use the CONFIGURE command on any of these devices.

To invoke the CONFIGURE command enter:


   discutil>CONFIGURE [LDEV=]ldev
            [CLASS=]devclass [PATH=]path

For example:


   discutil>CONFIGURE 21 DISC 6/4.0.0

DISMOUNT

Use the DISMOUNT command to logically dismount a volume. This command removes the volume entry corresponding to the specified ldev from DISCUTIL's mounted volume table, thus making it inaccessible to DISCUTIL. After a volume has been logically dismounted, the media or disk pack on the corresponding ldev can be spun down, new media mounted and spun up, then logically mounted with the MOUNT command. DISCUTIL will then recognize the new media.

To invoke the DISMOUNT command enter:


   discutil>DISMOUNT [LDEV=]ldev

For example:


   discutil>DISMOUNT 4

DO

Use the DO command to re-execute a command from the command history stack/queue.

To invoke DO enter:


   discutil> DO [ [CMD=]cmdid]

For example, to re-execute the fifth command, enter:


   discutil>DO 5

DSTAT

Use this command to display information about each mounted volume (i.e., any volume that is currently listed in the mounted volume table). To invoke DSTAT enter:


   discutil>DSTAT

DSTAT displays the ldev on which the volume is mounted, the type ID of the device, the type (STATUS) of the volume, the volume name, and the physical path as shown in the example below:


  LDEV-TYPE    STATUS     VOLUME ( VOLUME SET-GEN )          PATH
 -----------  --------   -----------------------------      ------
  1-079350     MASTER    MPEXL_SYSTEM_VOLUME_SET:MEMBER1     8.0.0
  2-079350     MEMBER    MPEXL_SYSTEM_VOLUME_SET:MEMBER2     8.0.1
  3-079350     MEMBER    MPEXL_SYSTEM_VOLUME_SET:MEMBER3     8.0.2
 14-079350     MASTER    OFFICIAL:MASTER                     8.0.4

EXIT

Use the EXIT command to terminate DISCUTIL and automatically begin a system reboot. To exit DISCUTIL enter:


   discutil>EXIT

When the ISL> prompt reappears, you may use the START command to restart your system or choose another standalone utility. (To see a list of the utilities available to you, enter LS.)

HELP

Use this command to get online help text for DISCUTIL commands. If you specify a command name HELP displays text for that command. If you don't specify a command, you will see a list of all available commands and their syntax.

To invoke HELP enter:


   discutil>HELP [ [CMD=] cmdname]

For example, to see a list of all commands and their syntax, enter:


   discutil>HELP

Or, to see information about the MOUNT command, enter:


   :HELP MOUNT

LISTREDO

Use this command to display the command line history stack/queue, ordered from the least to the most recent command with absolute command reference numbers preceding each command. Use LISTREDO in conjunction with the DO command to reissue commands you previously entered.

To invoke LISTREDO enter:


   discutil>LISTREDO

MOUNT

The MOUNT command is used to mount an unmounted volume. If the ldev represents a disk and if the device is responding, DISCUTIL will attempt to mount the volume. Only MASTER or MEMBER volumes can be mounted. Once mounted, a volume becomes available to DISCUTIL and is added to its mounted volume table. The ldev must be configured prior to mounting a volume on it.

To invoke MOUNT enter:


   discutil>MOUNT [LDEV=]ldev

For example:


   discutil>MOUNT 4

PDEV

The PDEV command displays the volume set name, volume number, and physical device path for all the disks known to DISCUTIL. All disks that are configured successfully, either at invocation or by the CONFIGURE command, are known to DISCUTIL. DISCUTIL reads the mounted volume table and uses the table information to configure the disks listed in the table.

The volume number is the volume's number in a volume set. For example, in a volume set of three volumes, each volume is given a number from one to three. This allows you to determine if you have all volumes of a volume set configured.

To invoke PDEV enter:


   discutil>PDEV

The system responds with a display similar to:


   CURRENT DEVICE CONFIGURATION:

     LDEV : 1
       VOLUME SET NAME : MPEXL_SYSTEM_VOLUME_SET
       VOLUME NUMBER   : 1
       PATH            : 2/4.0.0

     LDEV : 21
       VOLUME SET NAME : ACCOUNTING_VOL_SET
       VOLUME NUMBER   : 1
       PATH            : 6/4.0.0

     LDEV : 22
       VOLUME SET NAME : ACCOUNTING_VOL_SET
       VOLUME NUMBER   : 2
       PATH            : 6/4.0.1

REDO

Use REDO to modify and re-execute a command in the command history stack.

To invoke REDO enter:


   discutil>REDO [ [CMD=]cmid]

For example:


   discutil>REDO 5

This command would re-execute the fifth command entered after allowing you to modify it.

To re-execute the last command entered enter:


   discutil>REDO

SAVE

Use SAVE to retrieve files from disk and copy them to magnetic tape. You might use SAVE after a system failure, when a directory has been corrupted, or when a disk becomes inaccessible to the operating system.

If the volume label or the label table extent blocks are corrupt, SAVE will stop retrieving files from that disk and move onto the next.

Saving one set of files

You can tell DISCUTIL which files you want to copy to tape. The file(s) must reside on a disk that was mounted manually or during the startup of DISCUTIL.

To specify which files you want to save with DISCUTIL, do the following:

At the discutil> prompt, enter the SAVE command.
At the ENTER FILE SET TO BE SAVED prompt, specify the files you want copied using either MPE or HFS syntax. You can replace any part of the file set specification with @ to indicate all members of the set.
At the prompt TRAVERSE DIRECTORIES UNDER FILESET (Y/N), press RETURN to not save any hierarchical directories.
At the prompt ENTER THE LDEV, press return to tell the system to search all logical disk devices for the files. To search a single disk, enter its LDEV number.
At the prompt ENTER THE VOLUME SET NAME, press RETURN to search all disks. To search one set, specify the set.
At the prompt ENTER THE MODIFICATION DATE (MM/DD/YYYY), enter a date to save only those files in the file set that have been modified on or since a certain date.
At the prompt ENTER THE TAPE LDEV, enter the LDEV number of the tape drive on which you want to store the files.

DISCUTIL searches the label tables of all ldevs specified for the indicated file(s). Each time a file is found, and when the file is successfully written to tape, it prints a message. You may also see other messages indicating that an error has occured while DISCUTIL was saving a file.

If the end of a tape is reached before the procedure is complete, DISCUTIL will prompt you to mount a new tape. Once you have done so, SAVE continues until all specified files are copied. At that point, the ENTER FILE SET TO BE SAVED: prompt appears again so that you may specify additional files sets.

NOTE: Do not manually rewind the tapes. DISCUTIL will do this automatically when it has properly finished the process.

Saving multiple file sets

To save multiple sets of files, do the following:

Specify the first file set you want saved, answering each of the questions DISCUTIL asks. Refer to the preceding set of steps for information.
When you see the ENTER FILE SET TO BE SAVED prompt for the second time, press RETURN to complete the first tape set and rewind the tape.
At the discutil> prompt, enter the SAVE command again. (This begins the save procedure for the next file set.)

The following is a short sample of the interaction between a user and DISCUTIL during SAVE:


discutil>SAVE

*********************************************************************
***************************** WARNING!!! *****************************
**** MANUALLY REWINDING THE TAPE DRIVE AND STARTING A NEW TAPESET ****
**** BEFORE THE CURRENT SAVE COMMAND IS COMPLETE WILL CAUSE FILES ****
**** TO BE LOST!!!  TYPE (Return) at "ENTER FILE SET TO BE SAVED:"****
**** to complete the SAVE properly. SEE HELP "SAVE".              ****
**********************************************************************

   ENTER FILE SET TO BE SAVED: MYFILE.JOHN.SMITH

   TRAVERSE DIRECTORIES UNDER FILESET (Y/N)? n

   ENTER THE LDEV: 3

   ENTER THE MODIFICATION DATE(MM/DD/YYYY):05/25/1994

   ENTER THE TAPE LDEV: 7

   MYFILE   .JOHN   .SMITH  - LDEV 3 - ADDR $0002CA0 - FOUND
   MYFILE   .JOHN   .SMITH  - LDEV 3 - ADDR $0002CA0 - SAVED

**********************************************************************
***************************** WARNING!!! *****************************
**** MANUALLY REWINDING THE TAPE DRIVE AND STARTING A NEW TAPESET ****
**** BEFORE THE CURRENT SAVE COMMAND IS COMPLETE WILL CAUSE FILES ****
**** TO BE LOST!!!  TYPE (Return) at "ENTER FILE SET TO BE SAVED:"****
**** to complete the SAVE properly. SEE HELP "SAVE".              ****
**********************************************************************

   ENTER FILE SET TO BE SAVED:

SHOWDEV

The SHOWDEV command displays information about each device that is currently in the system configuration. For each configured device, the device's ldev, class, and physical are displayed.

To invoke SHOWDEV enter:


   discutil>SHOWDEV

The system responds with a display similar to the following:


       1      DISC    2/4.0.0
       3      DISC    2/4.0.2
       7      TAPE    6/4.3.0
      20  TERMINAL    2/4.1.0
      21      DISC    6/4.0.0
      25      DISC    2/8.0.0

TAPE

Use the TAPE command to display the ldev number of the current tape or to specify a new current tape. If the ldev parameter is omitted, the current tape ldev is displayed. If the ldev parameter is supplied, that ldev will become the new tape ldev. The ldev must have been configured as a tape.

To invoke TAPE enter:


   discutil>TAPE [ [LDEV=]ldev]

For example, to see the current tape drive enter:


   discutil>TAPE

To assign a logical device number as the current tape drive enter:


   discutil>TAPE 7

UNCONFIG

Use the UNCONFIG command to remove a device from the system's configuration. This frees or releases the corresponding ldev and physical path, making them available for reassignment with the CONFIGURE command.

To invoke UNCONFIG enter:


   discutil>UNCONFIG [LDEV=] ldev

For example:


   discutil>UNCONFIG 14

DISCUTIL messages and error handling

DISCUTIL displays three types of messages:

information messages, which inform the operator about the status of DISCUTIL
warning messages, which generally occur when the operator has made an error during data input. Warning messages begin with WARNING - .
error messages, which tell the Operator which errors DISCUTIL has encountered; typically, device errors. Error messages begin with ERROR - .

If a tape error occurs you must re-enter all file sets when prompted for a new tape unless the file sets were entered while a previous tape was mounted. If the tape error occurred while a previous tape was mounted DISCUTIL will automatically resave all files on the bad tape.

If an end-of-tape (EOT) is encountered in the middle of a file during DISCUTIL activity, the break in the file will be placed on a page boundary. If a tape write error occurs, DISCUTIL saves all files on the corrupt tape to a new tape. If part of that corrupt file is on the previous tape, the whole file is written to the new tape. Two end-of-file (EOF) marks are written to the tape any time DISCUTIL cannot save the entire file on a tape. VOLUTIL RECOVER is sensitive to this message and aborts that file's recovery at a double EOF before continuing.

Additional Discussion

For more information on the RECOVER command of VOLUTIL refer to the Volume Management Reference Manual.

For more information on resetting the system refer to the System Startup, Configuration, and Shutdown Reference Manual.

Chapter 6 DISCUTIL

Chapter 7 EDIT/3000

Operation

MPE documents

DISCUTIL Commands

CONFIGURE

DISMOUNT

DO

DSTAT

EXIT

HELP

LISTREDO

MOUNT

PDEV

REDO

SAVE

Saving one set of files

Saving multiple file sets

SHOWDEV

TAPE

UNCONFIG

DISCUTIL messages and error handling