Section: BerkeleyDB Utilities (1)
Updated: 06 December 2016
db_recover - Recover the database to a consistent state
[-cefVv] [-h home
] [-P password
] [-t [[CC]YY]MMDDhhmm[.SS]]]
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.
Note that this utility performs the same action as if the environment is opened with
the DB_RECOVER flag.
If DB_RECOVER is specified on environment open, then use of this utility is not necessary.
Perform catastrophic recovery instead of normal recovery.
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.
Display a message on the standard output showing the percent of recovery completed.
- -h home
Specify a home directory for the database environment; by
default, the current working directory is used.
- -P password
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.
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:
The first two digits of the year (the century).
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 "CC" value of 19. Otherwise,
a "YY" value of 20 is used.
The month of the year, from 1 to 12.
The day of the month, from 1 to 31.
The hour of the day, from 0 to 23.
The minute of the hour, from 0 to 59.
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.
Write the library version number to the standard output, and exit.
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
If the failure was not catastrophic, the files present on the system at the
time of failure are sufficient 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).
utility exits 0 on success, and >0 if an error occurs.
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
If the application(s) that use the environment make use of any of the following methods:
then in order for this utility to run correctly, you need a DB_CONFIG file which sets the proper paths using the add_data_dir, or set_lg_dir configuration parameters.