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db_recover
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<pre>db_recover [-cefVv] [-h home] [-P password] [-t [[CC]YY]MMDDhhmm[.SS]]]</pre>
Description
<a name="2"></a>
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<ul compact><li>Perform catastrophic recovery instead of normal recovery.</ul>
-e<ul compact><li>Retain the environment after running recovery. This option
will rarely be used unless a <a href="../../db4-devel-4.7.25/ref/env/db_config.html#DB_CONFIG">DB_CONFIG</a> file is present in the
home directory. If a <a href="../../db4-devel-4.7.25/ref/env/db_config.html#DB_CONFIG">DB_CONFIG</a> file is not present, then the
regions will be created with default parameter values.</ul>
-f<ul compact><li>Display a message on the standard output showing the
percent of recovery completed.</ul>
-h<ul compact><li>Specify a home directory for the database environment; by
default, the current working directory is used.</ul>
-P<ul compact><li>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.</ul>
-t<ul compact><li>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:</ul>
 
CC<ul compact><li>The first two digits of the year (the century).</ul>
YY<ul compact><li>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 "CC" value of 20 is used.</ul>
MM<ul compact><li>The month of the year, from 1 to 12.</ul>
DD<ul compact><li>The day of the month, from 1 to 31.</ul>
hh<ul compact><li>The hour of the day, from 0 to 23.</ul>
mm<ul compact><li>The minute of the hour, from 0 to 59.</ul>
SS<ul compact><li>The second of the minute, from 0 to 61.</ul>
 
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<ul compact><li>Write the library version number to the standard output, and exit.</ul>
-v<ul compact><li>Run in verbose mode.</ul>
 
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
<a href="../../db4-devel-4.7.25/ref/transapp/archival.html">Archival Procedures</a>. For
further information on performing recovery, see
<a href="../../db4-devel-4.7.25/ref/transapp/recovery.html">Recovery Procedures</a>.
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).
The db_recover utility exits 0 on success, and &gt;0 if an error occurs.
 Environment Variables
 
DB_HOME<ul compact><li>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 <a href="../../db4-devel-4.7.25/api_c/env_open.html">DB_ENV-&gt;open</a>.</ul>
 
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