Resynchronising Databases for Normal FailSafe

This procedure is used to resynchronise the primary/secondary pair and resume FailSafe operation. It would normally be executed after the following steps have been completed.

Note

  • This procedure must be carried out on the primary database.
  • Ensure that all clean logs, except the current clean log, have been restored to the secondary database.
  • Transaction Logging must be active before you can resynchronise the databases. If necessary, return to the Configuration and Setup Menu and select option 2, before continuing with this procedure.

Procedure

  1. Select option 4 on the Database Recovery menu. A message is displayed describing the purpose of the procedure and prompting you to confirm that you wish to continue. When you enter y at the confirmation prompt, the remote configuration is checked. If remote database configuration is incorrect, abort this procedure and select option 1 on the Database Recovery menu, then re-run procedure.

  2. A check is then made to see if the secondary database is up-to-date, except for the current active clean log on the primary.

    The following error message indicates that you have restored the wrong database save, or that logging has never been run on the restored database. If in doubt, call your NEC Software Solutions representative.

    Warning: Unable to identify remote Clean log and 
unable to continue with this procedure.
Hit return to continue:

    If the secondary database has not been restored up-to-date using Database Recovery option 3, the following messages are displayed:

    Warning: Unable to resynchronise databases for normal failsafe.
You must first select option 3 to restore Clean Log(s) onto the secondary database.
Hit return to continue:

    Also a check is made on the size of the current clean log on the primary. If the log size exceeds MaxClogSize (defined in database config file) or 50 Megabytes (if MaxClogSize is not defined), the following message is displayed:

    Warning: Current Clean Log is too big for resynchronisation.
    Select option 1 from Routine Maintenance to Switch Clean Log,
    followed by option 3 from Database Recovery to Restore Clean Log onto the Secondary Database.
    Then select this option.

  3. If all checks are passed successfully, then re-synchronisation proceeds with the following menu prompt to switch clean logs.

    Switch to :
1.  Another Clean Log for today (CLOG990817-02)
2.  Next Day's Clean Log (CLOG990818-01)
3.  Clean Log for named day or date
4.  A named Clean Log
Enter option (1-4) : _

    Select the option you require. See Clean Log Menu Options for a list of the above menu options.

  4. When you have selected the new clean log name, the following operations are carried out.

    • The primary log file is created.

    • The primary clean log is switched to start synchronisation.

      When the switch is complete, you are prompted, as follows:

      Copy previous_clean_log to the secondary to allow restore to proceed (y/n/q) :

      Enter y  to complete the resynchronisation. If you answer n, synchronisation will not be completed.

  5. Once synchronisation is complete you are prompted:

    Hit return to continue :

    This returns you to the Database Recovery menu and normal FailSafe operation is resumed.