<varname>primary_conninfo</> as well.

</para>

<para>

You can use <varname>archive_cleanup_command</> to prune the archive of

files no longer needed by the standby.

</para>

<para>

If you're setting up the standby server for high availability purposes,

set up WAL archiving, connections and authentication like the primary

is not required.

</para>

<para>

If you're using a WAL archive, its size can be minimized using the <xref

linkend="archive-cleanup-command"> parameter to remove files that are no

longer required by the standby server.

The <application>pg_archivecleanup</> utility is designed specifically to

be used with <varname>archive_cleanup_command</> in typical single-standby

configurations, see <xref linkend="pgarchivecleanup">.

Note however, that if you're using the archive for backup purposes, you

need to retain files needed to recover from at least the latest base

backup, even if they're no longer needed by the standby.

</para>

<para>

A simple example of a <filename>recovery.conf</> is:

<programlisting>

standby_mode = 'on'

primary_conninfo = 'host=192.168.1.50 port=5432 user=foo password=foopass'

restore_command = 'cp /path/to/archive/%f %p'

trigger_file = '/path/to/trigger_file'

archive_cleanup_command = 'pg_archivecleanup /path/to/archive %r'

</programlisting>

</para>

the primary to allow them to be connected simultaneously.

</para>

<para>

If you're using a WAL archive, its size can be minimized using

the <varname>archive_cleanup_command</> option to remove files that are

no longer required by the standby server. Note however, that if you're

using the archive for backup purposes, you need to retain files needed

to recover from at least the latest base backup, even if they're no

longer needed by the standby.

</para>

</sect2>

<sect2 id="streaming-replication">

</indexterm>

<para>

<application>pg_archivecleanup</> is designed to cleanup an archive when used

as an <literal>archive_cleanup_command</literal> when running with

<literal>standby_mode = on</literal>. <application>pg_archivecleanup</> can

also be used as a standalone program to clean WAL file archives.

<application>pg_archivecleanup</> is designed to be used as an

<literal>archive_cleanup_command</literal> to clean up WAL file archives when

running as a standby server (see <xref linkend="warm-standby">).

<application>pg_archivecleanup</> can also be used as a standalone program to

clean WAL file archives.

</para>

<para>

server to use <application>pg_archivecleanup</>, put this into its

<filename>recovery.conf</filename> configuration file:

<programlisting>

archive_cleanup_command = 'pg_archivecleanup <replaceable>archiveDir</> %r'

archive_cleanup_command = 'pg_archivecleanup <replaceable>archivelocation</> %r'

</programlisting>

where <replaceable>archiveDir</> is the directory from which WAL segment

files should berestored.

where <replaceable>archivelocation</> is the directory from which WAL segment

files should beremoved.

</para>

<para>

When used within <literal>archive_cleanup_command</literal>,

all WAL files logically preceding the value of the <literal>%r</>

will be removed <replaceable>archivelocation</>. This minimizes

the number of files that need to be retained, while preserving

crash-restart capability. Use of this parameter is appropriate if the

<replaceable>archivelocation</> is a transient staging area for this

particular standby server, but <emphasis>not</> when the

<replaceable>archivelocation</> is intended as a long-term WAL archive area.

When used within <xref linkend="archive-cleanup-command">, all WAL files

logically preceding the value of the <literal>%r</> argument will be removed

from <replaceable>archivelocation</>. This minimizes the number of files

that need to be retained, while preserving crash-restart capability. Use of

this parameter is appropriate if the <replaceable>archivelocation</> is a

transient staging area for this particular standby server, but

<emphasis>not</> when the <replaceable>archivelocation</> is intended as a

long-term WAL archive area, or when multiple standby servers are recovering

from the same archive location.

</para>

<para>

The full syntax of <application>pg_archivecleanup</>'s command line is

</indexterm>

<listitem>

<para>

This parameter specifies a shell command that will be executed at

every restartpoint. This parameter is optional. The purpose of the

<varname>archive_cleanup_command</> is to provide a mechanism for cleaning

up old archived WAL files that are no longer needed by the standby

server.

Any <literal>%r</> is replaced by the name of the file

containing the last valid restart point. That is the earliest file that

must be kept to allow a restore to be restartable, so this information

can be used to truncate the archive to just the minimum required to

support restart from the current restore. <literal>%r</> would

typically be used in a warm-standby configuration

(see <xref linkend="warm-standby">).

Write <literal>%%</> to embed an actual <literal>%</> character

in the command.

This optional parameter specifies a shell command that will be executed

at every restartpoint. The purpose of

<varname>archive_cleanup_command</> is to provide a mechanism for

cleaning up old archived WAL files that are no longer needed by the

standby server.

Any <literal>%r</> is replaced by the name of the file containing the

last valid restart point.

That is the earliest file that must be <emphasis>kept</> to allow a

restore to be restartable, and so all files earlier than <literal>%r</>

may be safely removed.

This information can be used to truncate the archive to just the

minimum required to support restart from the current restore.

The <application>pg_archivecleanup</> utility provided in

<literal>contrib</> (see <xref linkend="pgarchivecleanup">) serves as a

convenient target for <varname>archive_cleanup_command</> in typical

single-standby configurations, for example:

<programlisting> archive_cleanup_command = 'pg_archivecleanup /mnt/server/archivedir %r' </programlisting>

Note however that if multiple standby servers are restoring from the

same archive directory, you will need to ensure that you do not delete

WAL files until they are no longer needed by any of the servers.

<varname>archive_cleanup_command</> would typically be used in a

warm-standby configuration (see <xref linkend="warm-standby">).

Write <literal>%%</> to embed an actual <literal>%</> character in the

command.

</para>

<para>

If the command returns a non-zero exit status then a WARNING log