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<p>Library Version 11.2.5.3</p>
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<h2 class="title" style="clear: both"><a id="db_recover"></a>db_recover</h2>
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<pre class="programlisting">db_recover [-cefVv] [-h home] [-P password] [-t [[CC]YY]MMDDhhmm[.SS]]] </pre>
<p>
The <span class="command"><strong>db_recover</strong></span> 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
<span class="command"><strong>db_recover</strong></span> has run, and all uncommitted transactions will be
completely undone.
</p>
<p>
Note that this utility performs the same action as if the
environment is opened with the
<a class="link" href="envopen.html#envopen_DB_RECOVER">DB_RECOVER</a>
flag. If <code class="literal">DB_RECOVER</code> is specified on environment open,
then use of this utility is not necessary.
</p>
<div class="note" style="margin-left: 0.5in; margin-right: 0.5in;">
<h3 class="title">Note</h3>
<p>
If the application(s) that use the environment make use of
any of the following methods:
</p>
<table class="simplelist" border="0" summary="Simple list">
<tr>
<td>
<a class="xref" href="envadd_data_dir.html" title="DB_ENV->add_data_dir()">DB_ENV->add_data_dir()</a>
</td>
</tr>
<tr>
<td>
<a class="xref" href="envset_data_dir.html" title="DB_ENV->set_data_dir()">DB_ENV->set_data_dir()</a>
</td>
</tr>
<tr>
<td>
<a class="xref" href="envset_lg_dir.html" title="DB_ENV->set_lg_dir()">DB_ENV->set_lg_dir()</a>
</td>
</tr>
</table>
<p>
then in order for this utility to run correctly, you need a
<a href="../../programmer_reference/env_db_config.html#env_db_config.DB_CONFIG" class="olink">DB_CONFIG</a>
file which sets the proper paths using the
<a class="xref" href="add_data_dir_parameter.html" title="add_data_dir">add_data_dir</a>, or
<a class="xref" href="set_lg_dir_parameter.html" title="set_lg_dir">set_lg_dir</a>
configuration parameters.
</p>
</div>
<p>
The options are as follows:
</p>
<div class="itemizedlist">
<ul type="disc">
<li>
<p>
<span class="bold"><strong>-c</strong></span>
</p>
<p>
Perform catastrophic recovery instead of normal recovery.
</p>
</li>
<li>
<p>
<span class="bold"><strong>-e</strong></span>
</p>
<p>
Retain the environment after running recovery. This
option will rarely be used unless a <a href="../../programmer_reference/env_db_config.html#env_db_config.DB_CONFIG" class="olink">DB_CONFIG</a> file is
present in the home directory. If a <a href="../../programmer_reference/env_db_config.html#env_db_config.DB_CONFIG" class="olink">DB_CONFIG</a> file is
not present, then the regions will be created with default
parameter values.
</p>
</li>
<li>
<p>
<span class="bold"><strong>-f</strong></span>
</p>
<p>
Display a message on the standard output showing the percent of
recovery completed.
</p>
</li>
<li>
<p>
<span class="bold"><strong>-h</strong></span>
</p>
<p>
Specify a home directory for the database environment; by default, the
current working directory is used.
</p>
</li>
<li>
<p>
<span class="bold"><strong>-P</strong></span>
</p>
<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.
</p>
</li>
<li>
<p>
<span class="bold"><strong>-t</strong></span>
</p>
<p>
Recover to the time specified rather than to the most current possible
date. The timestamp argument should be in the form
<code class="literal">[[CC]YY]MMDDhhmm[.SS]</code> where each pair of letters represents the
following:
</p>
<div class="itemizedlist">
<ul type="circle">
<li>
<p>
<span class="bold"><strong>CC</strong></span>
</p>
<p>
The first two digits of the year (the century).
</p>
</li>
<li>
<p>
<span class="bold"><strong>YY</strong></span>
</p>
<p>
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.
</p>
</li>
<li>
<p>
<span class="bold"><strong>MM</strong></span>
</p>
<p>
The month of the year, from 1 to 12.
</p>
</li>
<li>
<p>
<span class="bold"><strong>DD</strong></span>
</p>
<p>
The day of the month, from 1 to 31.
</p>
</li>
<li>
<p>
<span class="bold"><strong>hh</strong></span>
</p>
<p>
The hour of the day, from 0 to 23.
</p>
</li>
<li>
<p>
<span class="bold"><strong>mm</strong></span>
</p>
<p>
The minute of the hour, from 0 to 59.
</p>
</li>
<li>
<p>
<span class="bold"><strong>SS</strong></span>
</p>
<p>
The second of the minute, from 0 to 61.
</p>
</li>
</ul>
</div>
<p>
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.
</p>
</li>
<li>
<p>
<span class="bold"><strong>-V</strong></span>
</p>
<p>
Write the library version number to the standard output, and exit.
</p>
</li>
<li>
<p>
<span class="bold"><strong>-v</strong></span>
</p>
<p>
Run in verbose mode.
</p>
</li>
</ul>
</div>
<p>
In the case of catastrophic recovery, an archival copy — or
<span class="emphasis"><em>snapshot</em></span> — 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).
<span>
For further information on creating a database snapshot, see
<a href="../../programmer_reference/transapp_archival.html" class="olink">Archival Procedures</a>.
For further information on performing recovery, see
<a href="../../programmer_reference/transapp_recovery.html" class="olink">Recovery Procedures</a>.
</span>
</p>
<p>
If the failure was not catastrophic, the files present on the system
at the time of failure are sufficient to perform recovery.
</p>
<p>
If log files are missing, <span class="command"><strong>db_recover</strong></span> will identify the missing log
file(s) and fail, in which case the missing log files need to be
restored and recovery performed again.
</p>
<p>
The <span class="command"><strong>db_recover</strong></span> utility uses a Berkeley DB
environment (as described for the <span class="bold"><strong>-h</strong></span>
option, the environment variable
<span class="bold"><strong>DB_HOME</strong></span>, 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, <span class="command"><strong>db_recover</strong></span> should always be given the chance to detach
from the environment and exit gracefully. To cause <span class="command"><strong>db_recover</strong></span> to
release all environment resources and exit cleanly, send it an
interrupt signal (SIGINT).
</p>
<p>
The <span class="command"><strong>db_recover</strong></span> utility exits 0 on success, and >0 if an error
occurs.
</p>
<div class="sect2" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h3 class="title"><a id="idp63173952"></a>Environment Variables</h3>
</div>
</div>
</div>
<div class="sect3" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h4 class="title"><a id="idp63257224"></a>DB_HOME</h4>
</div>
</div>
</div>
<p>
If the <span class="bold"><strong>-h</strong></span> 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 the
<a class="xref" href="envopen.html" title="DB_ENV->open()">DB_ENV->open()</a>
method.
</p>
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