<?xml version="1.0" encoding="UTF-8" standalone="no"?> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /> <title>db_recover</title> <link rel="stylesheet" href="apiReference.css" type="text/css" /> <meta name="generator" content="DocBook XSL Stylesheets V1.73.2" /> <link rel="start" href="index.html" title="Berkeley DB C++ API Reference" /> <link rel="up" href="utilities.html" title="Appendix A. Berkeley DB Command Line Utilities" /> <link rel="prev" href="db_printlog.html" title="db_printlog" /> <link rel="next" href="db_replicate.html" title="db_replicate" /> </head> <body> <div xmlns="" class="navheader"> <div class="libver"> <p>Library Version 11.2.5.3</p> </div> <table width="100%" summary="Navigation header"> <tr> <th colspan="3" align="center">db_recover</th> </tr> <tr> <td width="20%" align="left"><a accesskey="p" href="db_printlog.html">Prev</a> </td> <th width="60%" align="center">Appendix A. Berkeley DB Command Line Utilities </th> <td width="20%" align="right"> <a accesskey="n" href="db_replicate.html">Next</a></td> </tr> </table> <hr /> </div> <div class="sect1" lang="en" xml:lang="en"> <div class="titlepage"> <div> <div> <h2 class="title" style="clear: both"><a id="db_recover"></a>db_recover</h2> </div> </div> </div> <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="DbEnv::add_data_dir()">DbEnv::add_data_dir()</a> </td> </tr> <tr> <td> <a class="xref" href="envset_data_dir.html" title="DbEnv::set_data_dir()">DbEnv::set_data_dir()</a> </td> </tr> <tr> <td> <a class="xref" href="envset_lg_dir.html" title="DbEnv::set_lg_dir()">DbEnv::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="idp10763200"></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="idp10796384"></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="DbEnv::open()">DbEnv::open()</a> method. </p> </div> </div> </div> <div class="navfooter"> <hr /> <table width="100%" summary="Navigation footer"> <tr> <td width="40%" align="left"><a accesskey="p" href="db_printlog.html">Prev</a> </td> <td width="20%" align="center"> <a accesskey="u" href="utilities.html">Up</a> </td> <td width="40%" align="right"> <a accesskey="n" href="db_replicate.html">Next</a></td> </tr> <tr> <td width="40%" align="left" valign="top">db_printlog </td> <td width="20%" align="center"> <a accesskey="h" href="index.html">Home</a> </td> <td width="40%" align="right" valign="top"> db_replicate</td> </tr> </table> </div> </body> </html>