105 lines
2.7 KiB
Plaintext
105 lines
2.7 KiB
Plaintext
<chapter Id="failure">
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<title>Database Failures</title>
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<para>
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Database failures (or the possibility of such) must be assumed to be
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lurking, ready to strike at some time in the future. A prudent
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database administrator will plan for the inevitability of failures
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of all possible kinds, and will have appropriate plans and
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procedures in place <emphasis>before</emphasis> the failure occurs.
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</para>
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<para>
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Database recovery is necessary in the event of hardware or software
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failure. There are several categories of failures; some of these
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require relatively minor adjustments to the database, while others
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may depend on the existence of previously prepared database dumps
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and other recovery data sets. It should be emphasized that if your
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data is important and/or difficult to regenerate, then you should
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have considered and prepared for various failure scenarios.
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</para>
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<sect1 id="failure-disk-full">
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<title>Disk Filled</title>
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<para>
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A filled data disk may result in subsequent corruption of database
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indexes, but not of the fundamental data tables. If the WAL files
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are on the same disk (as is the case for a default configuration)
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then a filled disk during database initialization may result in
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corrupted or incomplete WAL files. This failure condition is
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detected and the database will refuse to start up. You must free
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up additional space on the disk (or move the WAL area to another
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disk; see <xref linkend="wal-configuration">) and then restart the
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<application>postmaster</application> to recover from this condition.
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</para>
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</sect1>
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<sect1 id="failure-disk-failed">
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<title>Disk Failed</title>
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<para>
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Failure of any disk (or of a logical storage device such as a RAID
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subsystem) involved with an active database will require
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that the database be recovered from a previously prepared database
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dump. This dump must be prepared using
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<application>pg_dumpall</application>, and updates to the database
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occurring after the database installation was dumped will be lost.
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</para>
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</sect1>
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<!--
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<sect1>
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<title>File Corrupted</title>
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<para>
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</para>
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</sect1>
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<sect1>
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<title>Table Corrupted</title>
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<para>
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</para>
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</sect1>
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<sect1>
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<title></title>
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<para>
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</para>
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</sect1>
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<sect1>
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<title></title>
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<para>
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</para>
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</sect1>
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<sect1>
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<title></title>
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<para>
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</para>
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</sect1>
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-->
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</chapter>
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sgml-default-dtd-file:"./reference.ced"
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End:
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