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db_recover(1)             BSD General Commands Manual            db_recover(1)

NAME
     db_recover

SYNOPSIS
     db_recover [-ceVv] [-h home] [-P password] [-t [[CC]YY]MMDDhhmm[.SS]]

DESCRIPTION
     The db_recover utility must be run after an unexpected application, Berkeley DB, or system failure to
     restore the database to a consistent state. All committed transactions are guaranteed to appear after
     db_recover has run, and all uncommitted transactions will be completely undone.

     The options are as follows:

     -c
        Perform catastrophic recovery instead of normal recovery.

     -e
        Retain the environment after running recovery. This option will rarely be used unless a DB_CONFIG
        file is present in the home directory. If a DB_CONFIG file is not present, then the regions will be
        created with default parameter values.

     -h
        Specify a home directory for the database environment; by default, the current working directory is
        used.

     -P
        Specify an environment password. Although Berkeley DB utilities overwrite password strings as soon
        as possible, be aware there may be a window of vulnerability on systems where unprivileged users can
        see command-line arguments or where utilities are not able to overwrite the memory containing the
        command-line arguments.

     -t
        Recover to the time specified rather than to the most current possible date. The timestamp argument
        should be in the form [[CC]YY]MMDDhhmm[.SS] where each pair of letters represents the following:

        CC
           The first two digits of the year (the century).

        YY
           The second two digits of the year. If "YY" is specified, but "CC" is not, a value for "YY"
           between 69 and 99 results in a "YY" value of 19. Otherwise, a "YY" value of 20 is used.

        MM
           The month of the year, from 1 to 12.

        DD
           The day of the month, from 1 to 31.

        hh
           The hour of the day, from 0 to 23.

        mm
           The minute of the hour, from 0 to 59.

        SS
           The second of the minute, from 0 to 61.
        If the "CC" and "YY" letter pairs are not specified, the values default to the current year. If the
        "SS" letter pair is not specified, the value defaults to 0.

     -V
        Write the library version number to the standard output, and exit.

     -v
        Run in verbose mode.

     In the case of catastrophic recovery, an archival copy -- or snapshot -- of all database files must be
     restored along with all of the log files written since the database file snapshot was made. (If disk
     space is a problem, log files may be referenced by symbolic links). For further information on creating
     a database snapshot, see Archival Procedures. For further information on performing recovery, see
     Recovery Procedures.

     If the failure was not catastrophic, the files present on the system at the time of failure are suffi-cient sufficient
     cient to perform recovery.

     If log files are missing, db_recover will identify the missing log file(s) and fail, in which case the
     missing log files need to be restored and recovery performed again.

     The db_recover utility uses a Berkeley DB environment (as described for the -h option, the environment
     variable DB_HOME, or because the utility was run in a directory containing a Berkeley DB environment).
     In order to avoid environment corruption when using a Berkeley DB environment, db_recover should always
     be given the chance to detach from the environment and exit gracefully. To cause db_recover to release
     all environment resources and exit cleanly, send it an interrupt signal (SIGINT).

     The db_recover utility exits 0 on success, and >0 if an error occurs.

ENVIRONMENT
     DB_HOME  If the -h option is not specified and the environment variable DB_HOME is set, it is used as
              the path of the database home, as described in DB_ENV->open.

SEE ALSO
     db_archive(1), db_checkpoint(1), db_deadlock(1), db_dump(1), db_load(1), db_printlog(1), db_stat(1),
     db_upgrade(1), db_verify(1)

Darwin                         December 3, 2003                         Darwin