<!ENTITY pgCtl SYSTEM "pg_ctl-ref.sgml">

<!ENTITY pgDump SYSTEM "pg_dump.sgml">

<!ENTITY pgDumpall SYSTEM "pg_dumpall.sgml">

<!ENTITY pgReceivexlog SYSTEM "pg_receivexlog.sgml">

<!ENTITY pgResetxlog SYSTEM "pg_resetxlog.sgml">

<!ENTITY pgRestore SYSTEM "pg_restore.sgml">

<!ENTITY postgres SYSTEM "postgres-ref.sgml">

</varlistentry>

<varlistentry>

<term><option>-x</option></term>

<term><option>--xlog</option></term>

<term><option>-x <replaceable class="parameter">method</replaceable></option></term>

<term><option>--xlog=<replaceable class="parameter">method</replaceable></option></term>

<listitem>

<para>

Includes the required transaction log files (WAL files) in the

to consult the log archive, thus making this a completely standalone

backup.

</para>

<note>

<para>

The transaction log files are collected at the end of the backup.

Therefore, it is necessary for the

<xref linkend="guc-wal-keep-segments"> parameter to be set high

enough that the log is not removed before the end of the backup.

If the log has been rotated when it's time to transfer it, the

backup will fail and be unusable.

</para>

</note>

<para>

The following methods for collecting the transaction logs are

supported:

<variablelist>

<varlistentry>

<term><literal>f</literal></term>

<term><literal>fetch</literal></term>

<listitem>

<para>

The transaction log files are collected at the end of the backup.

Therefore, it is necessary for the

<xref linkend="guc-wal-keep-segments"> parameter to be set high

enough that the log is not removed before the end of the backup.

If the log has been rotated when it's time to transfer it, the

backup will fail and be unusable.

</para>

</listitem>

</varlistentry>

<varlistentry>

<term><literal>s</literal></term>

<term><literal>stream</literal></term>

<listitem>

<para>

Stream the transaction log while the backup is created. This will

open a second connection to the server and start streaming the

transaction log in parallel while running the backup. Therefore,

it will use up two slots configured by the

<xref linkend="guc-max-wal-senders"> parameter. As long as the

client can keep up with transaction log received, using this mode

requires no extra transaction logs to be saved on the master.

</para>

</listitem>

</varlistentry>

</variablelist>

</para>

</listitem>

</varlistentry>

The following command-line options control the database connection parameters.

<variablelist>

<varlistentry>

<term><option>-s <replaceable class="parameter">interval</replaceable></option></term>

<term><option>--statusint=<replaceable class="parameter">interval</replaceable></option></term>

<listitem>

<para>

Specifies the number of seconds between status packets sent back to the

server. This is required when streaming the transaction log (using

<literal>--xlog=stream</literal>) if replication timeout is configured

on the server, and allows for easier monitoring. The default value is

10 seconds.

</para>

</listitem>

</varlistentry>

<varlistentry>

<term><option>-h <replaceable class="parameter">host</replaceable></option></term>

<term><option>--host=<replaceable class="parameter">host</replaceable></option></term>

<!--

doc/src/sgml/ref/pg_receivexlog.sgml

PostgreSQL documentation

-->

<refentry id="app-pgreceivexlog">

<refmeta>

<refentrytitle>pg_receivexlog</refentrytitle>

<manvolnum>1</manvolnum>

<refmiscinfo>Application</refmiscinfo>

</refmeta>

<refnamediv>

<refname>pg_receivexlog</refname>

<refpurpose>streams transaction logs from a <productname>PostgreSQL</productname> cluster</refpurpose>

</refnamediv>

<indexterm zone="app-pgreceivexlog">

<primary>pg_receivexlog</primary>

</indexterm>

<refsynopsisdiv>

<cmdsynopsis>

<command>pg_receivexlog</command>

<arg rep="repeat"><replaceable>option</></arg>

</cmdsynopsis>

</refsynopsisdiv>

<refsect1>

<title>

Description

</title>

<para>

<application>pg_receivexlog</application> is used to stream transaction log

from a running <productname>PostgreSQL</productname> cluster. The transaction

log is streamed using the streaming replication protocol, and is written

to a local directory of files. This directory can be used as the archive

location for doing a restore using point-in-time recovery (see

<xref linkend="continuous-archiving">).

</para>

<para>

<application>pg_receivexlog</application> streams the transaction

log in real time as it's being generated on the server, and does not wait

for segments to complete like <xref linkend="guc-archive-command"> does.

For this reason, it is not necessary to set

<xref linkend="guc-archive-timeout"> when using

<application>pg_receivexlog</application>.

</para>

<para>

The transaction log is streamed over a regular

<productname>PostgreSQL</productname> connection, and uses the

replication protocol. The connection must be

made with a user having <literal>REPLICATION</literal> permissions (see

<xref linkend="role-attributes">), and the user must be granted explicit

permissions in <filename>pg_hba.conf</filename>. The server must also

be configured with <xref linkend="guc-max-wal-senders"> set high enough

to leave at least one session available for the stream.

</para>

</refsect1>

<refsect1>

<title>Options</title>

<para>

The following command-line options control the location and format of the

output.

<variablelist>

<varlistentry>

<term><option>-D <replaceable class="parameter">directory</replaceable></option></term>

<term><option>--dir=<replaceable class="parameter">directory</replaceable></option></term>

<listitem>

<para>

Directory to write the output to.

</para>

<para>

This parameter is required.

</para>

</listitem>

</varlistentry>

</variablelist>

</para>

<para>

The following command-line options control the running of the program.

<variablelist>

<varlistentry>

<term><option>-v</option></term>

<term><option>--verbose</option></term>

<listitem>

<para>

Enables verbose mode.

</para>

</listitem>

</varlistentry>

</variablelist>

</para>

<para>

The following command-line options control the database connection parameters.

<variablelist>

<varlistentry>

<term><option>-s <replaceable class="parameter">interval</replaceable></option></term>

<term><option>--statusint=<replaceable class="parameter">interval</replaceable></option></term>

<listitem>

<para>

Specifies the number of seconds between status packets sent back to the

server. This is required if replication timeout is configured on the

server, and allows for easier monitoring. The default value is

10 seconds.

</para>

</listitem>

</varlistentry>

<varlistentry>

<term><option>-h <replaceable class="parameter">host</replaceable></option></term>

<term><option>--host=<replaceable class="parameter">host</replaceable></option></term>

<listitem>

<para>

Specifies the host name of the machine on which the server is

running. If the value begins with a slash, it is used as the

directory for the Unix domain socket. The default is taken

from the <envar>PGHOST</envar> environment variable, if set,

else a Unix domain socket connection is attempted.

</para>

</listitem>

</varlistentry>

<varlistentry>

<term><option>-p <replaceable class="parameter">port</replaceable></option></term>

<term><option>--port=<replaceable class="parameter">port</replaceable></option></term>

<listitem>

<para>

Specifies the TCP port or local Unix domain socket file

extension on which the server is listening for connections.

Defaults to the <envar>PGPORT</envar> environment variable, if

set, or a compiled-in default.

</para>

</listitem>

</varlistentry>

<varlistentry>

<term><option>-U <replaceable>username</replaceable></option></term>

<term><option>--username=<replaceable class="parameter">username</replaceable></option></term>

<listitem>

<para>

User name to connect as.

</para>

</listitem>

</varlistentry>

<varlistentry>

<term><option>-w</></term>

<term><option>--no-password</></term>

<listitem>

<para>

Never issue a password prompt. If the server requires

password authentication and a password is not available by

other means such as a <filename>.pgpass</filename> file, the

connection attempt will fail. This option can be useful in

batch jobs and scripts where no user is present to enter a

password.

</para>

</listitem>

</varlistentry>

<varlistentry>

<term><option>-W</option></term>

<term><option>--password</option></term>

<listitem>

<para>

Force <application>pg_receivexlog</application> to prompt for a

password before connecting to a database.

</para>

<para>

This option is never essential, since

<application>pg_receivexlog</application> will automatically prompt

for a password if the server demands password authentication.

However, <application>pg_receivexlog</application> will waste a

connection attempt finding out that the server wants a password.

In some cases it is worth typing <option>-W</> to avoid the extra

connection attempt.

</para>

</listitem>

</varlistentry>

</variablelist>

</para>

<para>

Other, less commonly used, parameters are also available:

<variablelist>

<varlistentry>

<term><option>-V</></term>

<term><option>--version</></term>

<listitem>

<para>

Print the <application>pg_receivexlog</application> version and exit.

</para>

</listitem>

</varlistentry>

<varlistentry>

<term><option>-?</></term>

<term><option>--help</></term>

<listitem>

<para>

Show help about <application>pg_receivexlog</application> command line

arguments, and exit.

</para>

</listitem>

</varlistentry>

</variablelist>

</para>

</refsect1>

<refsect1>

<title>Environment</title>

<para>

This utility, like most other <productname>PostgreSQL</> utilities,

uses the environment variables supported by <application>libpq</>

(see <xref linkend="libpq-envars">).

</para>

</refsect1>

<refsect1>

<title>Notes</title>

<para>

When using <application>pg_receivexlog</application> instead of

<xref linkend="guc-archive-command">, the server will continue to

recycle transaction log files even if the backups are not properly

archived, since there is no command that fails. This can be worked

around by having an <xref linkend="guc-archive-command"> that fails

when the file has not been properly archived yet.

</para>

</refsect1>

<refsect1>

<title>Examples</title>

<para>

To stream the transaction log from the server at

<literal>mydbserver</literal> and store it in the local directory

<filename>/usr/local/pgsql/archive</filename>:

<screen>

<prompt>$</prompt> <userinput>pg_receivexlog -h mydbserver -D /home/pgbackup/archive</userinput>

</screen>

</para>

</refsect1>

<refsect1>

<title>See Also</title>

<simplelist type="inline">

<member><xref linkend="APP-PGBASEBACKUP"></member>

</simplelist>

</refsect1>

</refentry>

&pgConfig;

&pgDump;

&pgDumpall;

&pgReceivexlog;

&pgRestore;

&psqlRef;

&reindexdb;

/pg_basebackup

/pg_receivexlog