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Basic Rollforward Recovery

Before attempting the rollforward recovery process:

  • All of the recovery log files created while the Fileshare Server was active should be in the recovery log file directory (or the log file backup directory if one is specified in the database reference file).
  • The original data files (the backed up versions taken before the Fileshare Server was started) should be restored to their correct directories.

Use the /r (recover) option to invoke the Rollforward Recovery Utility. You must specify a database reference file when invoking the Rollforward Recovery Utility, for example:

fs /r dbase.ref [options]

Here, dbase.ref is the name of the database reference file used by the Rollforward Recovery Utility. This must be the same as the database reference file used by the Fileshare Server while it was running. The Rollforward Recovery Utility reads the database reference file to determine the location and name of the rollforward recovery log file(s) and the name(s) of the data file(s) to recover.

Note: You can select the data files you want to restore by erasing other entries from the database reference file using the Database Reference File Maintenance Utility (/e option) before invoking the Rollforward Recovery Utility.

You can use the Rollforward Recovery Utility to specify the following options:

  • /dt date-time

    Specifies that the Rollforward Recovery Utility restores the updates made to the data files up to the time specified. The format of date-time is YYMMDDHHMMSS (year, month, day, hour, minutes, seconds) specified numerically. When you do not specify this option, the Rollforward Recovery Utility applies all of the updates that are stored in the rollforward recovery log file.

    For example:

    fs /r dbase.ref /dt 931231235959

    invokes the Rollforward Recovery Utility using the database reference file dbase.ref. Only those updates that were made up to the end of 31 December 1993 are restored.

  • /v

    Causes the Rollforward Recovery Utility to display additional information about which recovery log files it is searching for and in which directories.

Updates can be recorded in multiple log files (see the section Rollforward Recovery Logging for further details). The Rollforward Recovery Utility scans the log file directory for the starter log file. If none is found, the directory is scanned for a backed-up starter log file. If a starter log file still cannot be found the same procedure is repeated with the searches being performed in the backup directory if one is specified in the database reference file. If the Rollforward Recovery Utility is able to locate the starter log file then the recovery procedure commences; if not an error is displayed and the recovery does not start.

Once the starter log file has been processed, the Rollforward Recovery Utility searches for a continuation log file. If no backup of the recovery log file was performed, there is no continuation log file and the recovery process terminates. The Rollforward Recovery Utility searches for the continuation log file in the log file directory and then in the log file backup directory. The recovery process continues using the continuation log file(s) until all of the updates have been recovered and applied to the data files.

If transactions were in progress when the server terminated, then these transactions will be recorded but not committed. In addition, if the server was forced to terminate, then all open files will record a close, even if they were in mid transaction. A rollforward recovery will not be able to commit these transactions and a subsequent normal close would be illegal. When this situation occurs, the user will be informed with the message:

FS290-W Uncommitted transaction recorded - cannot complete transaction.

followed by the name of the file that cannot complete the transaction.

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