Restoring the Database from the Most Recent Backup Tape

This procedure remakes the failed database by first replacing it with an empty database and then restoring the most recent backup of the database onto the new database.

Note

  • You cannot carry out this procedure while Transaction Logging is running. You must first stop logging using Configuration and Setup menu option 3. It may take up to 2 minutes after the stopping of Transaction Logging is initiated, before changes are flushed to the clean log. During that time, if you enter the S option, the status STOP IN PROGRESS is displayed.
  • Ensure that tlmenu is configured to use the same backup method for the database on which you are restoring the data as was used when the backup was saved (see Backup Methods used by tlmenu).

Caution

Executing this procedure will destroy all accounts and files on the database. Only database configuration information will be preserved. All data will then have to be recovered from backups and transaction logs.

Procedure

  1. Select option 1 on the Database Recovery menu. A message is displayed describing the purpose of the procedure and asking you to confirm that you wish to continue.

    If you enter y  at the confirmation prompt, the database is remade. Standard system files and programs are loaded into the new database and all DataBasic programs are cataloged.

  2. Once the remaking of the database is completed, you are prompted to restore the save with the message:

    OK to continue with Restore (y/n/q)  ? :

    Ensure that there is a suitable tape device available; then enter y  to continue with the restore.

  3. If the FILE-SAVE/Physical Save (Choose at time of save)  option was selected when defining the backup method used by tlmenu, you will be prompted to select the save method to be used:

    Select save method
        1. FILE-SAVE
        2. Physical Save
        Enter option (1-2) :

    Enter 1  or 2  as required.

    The prompts that follow depend on the save method that is selected (either in step 3 above or defined as the backup method used by tlmenu:

    • For FILE-SAVE, continue at step 4.
    • For Physical save, continue at step 8.
    • For dbsave, continue at step 10.

FILE-SAVE

  1. If the FILE-SAVE method is selected you will see the following prompts:
    Do you want to resize files during Restore (y/n/q) ? :

    If you enter y, the size (modulo) of those files which have previously been set up for resizing, will be changed during the restore. Note, however, that selection of this option may slow down the restore process considerably.

  2. A list of tape units configured on the database is then displayed, followed by the prompt:

    Enter LOCAL tape unit number for restore (tape_unit) :

    Enter the number of the tape device to be used to restore the save.

  3. A message similar to the following now is displayed:

    Mount save tape on tape unit tape_unit
    Are you ready to start the restore (y/n/q) ? :

    Ensure that the most recent save tape is mounted in the specified tape device and that the device is on-line. Then enter y.

  4. The tape is read and the tape label displayed for you to make sure that it is the correct tape. You are then prompted to confirm that the tape is correct. Ensure that the correct tape is mounted and then enter y  to execute the restore.

    Now go to step 11.

Physical Save

If the Physical Save method is selected you will see the following prompts:

  1. If you selected Physical Save from the Select save method menu (step 3), you will be prompted:
    Use default tape unit list [tapeList] (y/n/q) ? :
    • Enter y  to use the tape list (tapeList) that was selected when defining the backup method used by tlmenu.
    • Enter n  to select different tape units. The tapes that are available on the local database will be listed and you are prompted to select the one or ones you wish to use. Multiple tape numbers must be comma-separated.

  2. Are you ready to start the restore (y/n/q) ? :

    Enter y  to continue, n  to return to the Database Recovery menu, or q  to return to the host prompt.

    Now go to step 11.

dbsave

If the dbsave  method is selected you will see the following prompt:

  1. Are you ready to start the restore (y/n/q) ? :

    Enter y  to continue, n  to return to the Database Recovery menu, or q  to return to the host prompt.

Restore Completion

  1. You are then prompted:

    Please restore the REK file if available, OK to continue (y/n/q) ? :

    If you are using Data Encryption, you must now restore your copy of the REK file and load it with the LOAD-REK command. See Copying Encrypted Data to another Host for details.

    Enter y  when ready to continue.

  2. The restore ends with the message:

    Now restore the Clean Log(s) and restart Transaction Logging.
Hit return to continue:

    This returns you to the Database Recovery  menu. You must now use the Restore Clean Log(s) onto the Database  command (option 2 on the Database Recovery menu) to restore clean logs onto the restored database.