-<!-- $PostgreSQL: pgsql/doc/src/sgml/backup.sgml,v 2.83 2006/08/17 23:04:02 tgl Exp $ -->
+<!-- $PostgreSQL: pgsql/doc/src/sgml/backup.sgml,v 2.84 2006/09/15 21:55:07 momjian Exp $ -->
<chapter id="backup">
<title>Backup and Restore</title>
<listitem>
<para>
Start the server. The server will go into recovery mode and
- proceed to read through the archived WAL files it needs. Upon completion
+ proceed to read through the archived WAL files it needs. Should the
+ recovery be terminated because of an external error, the server can
+ simply be restarted and it will continue recovery. Upon completion
of the recovery process, the server will rename
<filename>recovery.conf</> to <filename>recovery.done</> (to prevent
accidentally re-entering recovery mode in case of a crash later) and then
recover to such a time, you must go back to your previous base backup
and roll forward from there.)
</para>
- </note>
+ </note>
+
+ <para>
+ If recovery finds a corruption in the WAL data then recovery will
+ complete at that point and the server will not start. The recovery
+ process could be re-run from the beginning, specifying a
+ <quote>recovery target</> so that recovery can complete normally.
+ If recovery fails for an external reason, such as a system crash or
+ the WAL archive has become inaccessible, then the recovery can be
+ simply restarted and it will restart almost from where it failed.
+ Restartable recovery works by writing a restartpoint record to the control
+ file at the first safely usable checkpoint record found after
+ <varname>checkpoint_timeout</> seconds.
+ </para>
+
<sect3 id="recovery-config-settings" xreflabel="Recovery Settings">
<title>Recovery Settings</title>