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<!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>27.2. Recovery Target Settings</title><link rel="stylesheet" type="text/css" href="stylesheet.css" /><link rev="made" href="pgsql-docs@lists.postgresql.org" /><meta name="generator" content="DocBook XSL Stylesheets Vsnapshot" /><link rel="prev" href="archive-recovery-settings.html" title="27.1. Archive Recovery Settings" /><link rel="next" href="standby-settings.html" title="27.3. Standby Server Settings" /></head><body><div xmlns="http://www.w3.org/TR/xhtml1/transitional" class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="5" align="center">27.2. Recovery Target Settings</th></tr><tr><td width="10%" align="left"><a accesskey="p" href="archive-recovery-settings.html" title="27.1. Archive Recovery Settings">Prev</a> </td><td width="10%" align="left"><a accesskey="u" href="recovery-config.html" title="Chapter 27. Recovery Configuration">Up</a></td><th width="60%" align="center">Chapter 27. Recovery Configuration</th><td width="10%" align="right"><a accesskey="h" href="index.html" title="PostgreSQL 11.5 Documentation">Home</a></td><td width="10%" align="right"> <a accesskey="n" href="standby-settings.html" title="27.3. Standby Server Settings">Next</a></td></tr></table><hr></hr></div><div class="sect1" id="RECOVERY-TARGET-SETTINGS"><div class="titlepage"><div><div><h2 class="title" style="clear: both">27.2. Recovery Target Settings</h2></div></div></div><p>
By default, recovery will recover to the end of the WAL log. The
following parameters can be used to specify an earlier stopping point.
At most one of <code class="varname">recovery_target</code>,
<code class="varname">recovery_target_lsn</code>, <code class="varname">recovery_target_name</code>,
<code class="varname">recovery_target_time</code>, or <code class="varname">recovery_target_xid</code>
can be used; if more than one of these is specified in the configuration
file, the last entry will be used.
</p><div class="variablelist"><dl class="variablelist"><dt id="RECOVERY-TARGET"><span class="term"><code class="varname">recovery_target</code><code class="literal"> = 'immediate'</code>
<a id="id-1.6.14.7.3.1.1.3" class="indexterm"></a>
</span></dt><dd><p>
This parameter specifies that recovery should end as soon as a
consistent state is reached, i.e. as early as possible. When restoring
from an online backup, this means the point where taking the backup
ended.
</p><p>
Technically, this is a string parameter, but <code class="literal">'immediate'</code>
is currently the only allowed value.
</p></dd><dt id="RECOVERY-TARGET-NAME"><span class="term"><code class="varname">recovery_target_name</code> (<code class="type">string</code>)
<a id="id-1.6.14.7.3.2.1.3" class="indexterm"></a>
</span></dt><dd><p>
This parameter specifies the named restore point (created with
<code class="function">pg_create_restore_point()</code>) to which recovery will proceed.
</p></dd><dt id="RECOVERY-TARGET-TIME"><span class="term"><code class="varname">recovery_target_time</code> (<code class="type">timestamp</code>)
<a id="id-1.6.14.7.3.3.1.3" class="indexterm"></a>
</span></dt><dd><p>
This parameter specifies the time stamp up to which recovery
will proceed.
The precise stopping point is also influenced by
<a class="xref" href="recovery-target-settings.html#RECOVERY-TARGET-INCLUSIVE">recovery_target_inclusive</a>.
</p></dd><dt id="RECOVERY-TARGET-XID"><span class="term"><code class="varname">recovery_target_xid</code> (<code class="type">string</code>)
<a id="id-1.6.14.7.3.4.1.3" class="indexterm"></a>
</span></dt><dd><p>
This parameter specifies the transaction ID up to which recovery
will proceed. Keep in mind
that while transaction IDs are assigned sequentially at transaction
start, transactions can complete in a different numeric order.
The transactions that will be recovered are those that committed
before (and optionally including) the specified one.
The precise stopping point is also influenced by
<a class="xref" href="recovery-target-settings.html#RECOVERY-TARGET-INCLUSIVE">recovery_target_inclusive</a>.
</p></dd><dt id="RECOVERY-TARGET-LSN"><span class="term"><code class="varname">recovery_target_lsn</code> (<code class="type">pg_lsn</code>)
<a id="id-1.6.14.7.3.5.1.3" class="indexterm"></a>
</span></dt><dd><p>
This parameter specifies the LSN of the write-ahead log location up
to which recovery will proceed. The precise stopping point is also
influenced by <a class="xref" href="recovery-target-settings.html#RECOVERY-TARGET-INCLUSIVE">recovery_target_inclusive</a>. This
parameter is parsed using the system data type
<a class="link" href="datatype-pg-lsn.html" title="8.20. pg_lsn Type"><code class="type">pg_lsn</code></a>.
</p></dd></dl></div><p>
The following options further specify the recovery target, and affect
what happens when the target is reached:
</p><div class="variablelist"><dl class="variablelist"><dt id="RECOVERY-TARGET-INCLUSIVE"><span class="term"><code class="varname">recovery_target_inclusive</code> (<code class="type">boolean</code>)
<a id="id-1.6.14.7.5.1.1.3" class="indexterm"></a>
</span></dt><dd><p>
Specifies whether to stop just after the specified recovery target
(<code class="literal">true</code>), or just before the recovery target
(<code class="literal">false</code>).
Applies when <a class="xref" href="recovery-target-settings.html#RECOVERY-TARGET-LSN">recovery_target_lsn</a>,
<a class="xref" href="recovery-target-settings.html#RECOVERY-TARGET-TIME">recovery_target_time</a>, or
<a class="xref" href="recovery-target-settings.html#RECOVERY-TARGET-XID">recovery_target_xid</a> is specified.
This setting controls whether transactions
having exactly the target WAL location (LSN), commit time, or transaction ID, respectively, will
be included in the recovery. Default is <code class="literal">true</code>.
</p></dd><dt id="RECOVERY-TARGET-TIMELINE"><span class="term"><code class="varname">recovery_target_timeline</code> (<code class="type">string</code>)
<a id="id-1.6.14.7.5.2.1.3" class="indexterm"></a>
</span></dt><dd><p>
Specifies recovering into a particular timeline. The default is
to recover along the same timeline that was current when the
base backup was taken. Setting this to <code class="literal">latest</code> recovers
to the latest timeline found in the archive, which is useful in
a standby server. Other than that you only need to set this parameter
in complex re-recovery situations, where you need to return to
a state that itself was reached after a point-in-time recovery.
See <a class="xref" href="continuous-archiving.html#BACKUP-TIMELINES" title="25.3.5. Timelines">Section 25.3.5</a> for discussion.
</p></dd><dt id="RECOVERY-TARGET-ACTION"><span class="term"><code class="varname">recovery_target_action</code> (<code class="type">enum</code>)
<a id="id-1.6.14.7.5.3.1.3" class="indexterm"></a>
</span></dt><dd><p>
Specifies what action the server should take once the recovery target is
reached. The default is <code class="literal">pause</code>, which means recovery will
be paused. <code class="literal">promote</code> means the recovery process will finish
and the server will start to accept connections.
Finally <code class="literal">shutdown</code> will stop the server after reaching the
recovery target.
</p><p>
The intended use of the <code class="literal">pause</code> setting is to allow queries
to be executed against the database to check if this recovery target
is the most desirable point for recovery.
The paused state can be resumed by
using <code class="function">pg_wal_replay_resume()</code> (see
<a class="xref" href="functions-admin.html#FUNCTIONS-RECOVERY-CONTROL-TABLE" title="Table 9.81. Recovery Control Functions">Table 9.81</a>), which then
causes recovery to end. If this recovery target is not the
desired stopping point, then shut down the server, change the
recovery target settings to a later target and restart to
continue recovery.
</p><p>
The <code class="literal">shutdown</code> setting is useful to have the instance ready
at the exact replay point desired. The instance will still be able to
replay more WAL records (and in fact will have to replay WAL records
since the last checkpoint next time it is started).
</p><p>
Note that because <code class="filename">recovery.conf</code> will not be renamed when
<code class="varname">recovery_target_action</code> is set to <code class="literal">shutdown</code>,
any subsequent start will end with immediate shutdown unless the
configuration is changed or the <code class="filename">recovery.conf</code> file is
removed manually.
</p><p>
This setting has no effect if no recovery target is set.
If <a class="xref" href="runtime-config-replication.html#GUC-HOT-STANDBY">hot_standby</a> is not enabled, a setting of
<code class="literal">pause</code> will act the same as <code class="literal">shutdown</code>.
</p></dd></dl></div></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="archive-recovery-settings.html">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="recovery-config.html">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="standby-settings.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top">27.1. Archive Recovery Settings </td><td width="20%" align="center"><a accesskey="h" href="index.html">Home</a></td><td width="40%" align="right" valign="top"> 27.3. Standby Server Settings</td></tr></table></div></body></html>
