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diff --git a/bdb/docs/ref/transapp/recovery.html b/bdb/docs/ref/transapp/recovery.html deleted file mode 100644 index 5be94bf417c..00000000000 --- a/bdb/docs/ref/transapp/recovery.html +++ /dev/null @@ -1,91 +0,0 @@ -<!--$Id: recovery.so,v 10.26 2000/08/16 17:50:40 margo Exp $--> -<!--Copyright 1997, 1998, 1999, 2000 by Sleepycat Software, Inc.--> -<!--All rights reserved.--> -<html> -<head> -<title>Berkeley DB Reference Guide: Recovery procedures</title> -<meta name="description" content="Berkeley DB: An embedded database programmatic toolkit."> -<meta name="keywords" content="embedded,database,programmatic,toolkit,b+tree,btree,hash,hashing,transaction,transactions,locking,logging,access method,access methods,java,C,C++"> -</head> -<body bgcolor=white> - <a name="2"><!--meow--></a> -<table><tr valign=top> -<td><h3><dl><dt>Berkeley DB Reference Guide:<dd>Transaction Protected Applications</dl></h3></td> -<td width="1%"><a href="../../ref/transapp/logfile.html"><img src="../../images/prev.gif" alt="Prev"></a><a href="../../ref/toc.html"><img src="../../images/ref.gif" alt="Ref"></a><a href="../../ref/transapp/filesys.html"><img src="../../images/next.gif" alt="Next"></a> -</td></tr></table> -<p> -<h1 align=center>Recovery procedures</h1> -<p>The fifth component of the infrastructure, recovery procedures, concerns -the recoverability of the database. After any application or system -failure, there are two possible approaches to database recovery: -<p><ol> -<p><li>There is no need for recoverability and all databases can be recreated -from scratch. While these applications may still need transaction -protection for other reasons, recovery usually consists of removing the -Berkeley DB environment home directory and all files it contains, and then -restarting the application. -<p><li>It is necessary to recover information after system or application -failure. In this case, recovery processing must be performed on any -database environments that were active at the time of the failure. -Recovery processing involves running the <a href="../../utility/db_recover.html">db_recover</a> utility or -calling the <a href="../../api_c/env_open.html">DBENV->open</a> function with the <a href="../../api_c/env_open.html#DB_RECOVER">DB_RECOVER</a> or -<a href="../../api_c/env_open.html#DB_RECOVER_FATAL">DB_RECOVER_FATAL</a> flags. -<p>During recovery processing, all database changes made by aborted or -unfinished transactions are undone and all database changes made by -committed transactions are redone, as necessary. Database applications -must not be restarted until recovery completes. After recovery -finishes, the environment is properly initialized so that applications -may be restarted. -</ol> -<p>If you intend to do recovery, there are two possible types of recovery -processing: -<p><ol> -<p><li><i>catastrophic</i> recovery. A failure that requires catastrophic -recovery is a failure where either the database or log files have been -destroyed or corrupted. For example, catastrophic failure includes the -case where the disk drive on which either the database or logs are -stored has been physically destroyed, or when the system's normal -filesystem recovery on startup is unable to bring the database and log -files to a consistent state. This is often difficult to detect, and -perhaps the most common sign of the need for catastrophic recovery is -when the normal recovery procedures fail. -<p>To restore your database environment after catastrophic failure, take -the following steps: -<p><ol> -<p><li>Restore the most recent snapshots of the database and log files from -the backup media into the system directory where recovery will be -performed. -<p><li>If any log files were archived since the last snapshot was made, they -should be restored into the Berkeley DB environment directory where recovery -will be performed. Make sure you restore them in the order in which -they were written. The order is important because it's possible that -the same log file appears on multiple backups and you want to run -recovery using the most recent version of each log file. -<p><li>Run the <a href="../../utility/db_recover.html">db_recover</a> utility, specifying its <b>-c</b> option, -or call the <a href="../../api_c/env_open.html">DBENV->open</a> function specifying the <a href="../../api_c/env_open.html#DB_RECOVER_FATAL">DB_RECOVER_FATAL</a> -flag. The catastrophic recovery process will review the logs and -database files to bring the environment databases to a consistent state -as of the time of the last uncorrupted log file that is found. It is -important to realize that only transactions committed before that date -will appear in the databases. -<p>It is possible to recreate the database in a location different than -the original, by specifying appropriate pathnames to the <b>-h</b> -option of the <a href="../../utility/db_recover.html">db_recover</a> utility. In order for this to work -properly, it is important that your application reference files by -names relative to the database home directory or the pathname(s) specified -in calls to <a href="../../api_c/env_set_data_dir.html">DBENV->set_data_dir</a>, instead of using full path names. -</ol> -<p><li><i>non-catastrophic</i> or <i>normal</i> recovery. If the -failure is non-catastrophic and the database files and log are both -accessible on a stable filesystem, run the <a href="../../utility/db_recover.html">db_recover</a> utility -without the <b>-c</b> option or call the <a href="../../api_c/env_open.html">DBENV->open</a> function -specifying the <a href="../../api_c/env_open.html#DB_RECOVER">DB_RECOVER</a> flag. The normal recovery process -will review the logs and database files to ensure that all changes -associated with committed transactions appear in the databases and that -all uncommitted transactions do not. -</ol> -<table><tr><td><br></td><td width="1%"><a href="../../ref/transapp/logfile.html"><img src="../../images/prev.gif" alt="Prev"></a><a href="../../ref/toc.html"><img src="../../images/ref.gif" alt="Ref"></a><a href="../../ref/transapp/filesys.html"><img src="../../images/next.gif" alt="Next"></a> -</td></tr></table> -<p><font size=1><a href="http://www.sleepycat.com">Copyright Sleepycat Software</a></font> -</body> -</html> |