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<chapter id="high-availability">

<title>High Availability, Load Balancing, and Replication</title>

</varlistentry>

<varlistentry>

<term>Warm Standby Using Point-In-Time Recovery (<acronym>PITR</>)</term>

<term>Warmand HotStandby Using Point-In-Time Recovery (<acronym>PITR</>)</term>

<listitem>

<para>

A warmstandbyserver (see <xref linkend="warm-standby">) can

be kept current by reading astream of write-ahead log (<acronym>WAL</>)

Warm and hotstandbyservers can be kept current by reading a

stream of write-ahead log (<acronym>WAL</>)

records. If the main server fails, the warm standby contains

almost all of the data of the main server, and can be quickly

made the new master database server. This is asynchronous and

can only be done for the entire database server.

</para>

<para>

A PITR warm standby server can be kept more up-to-date using the

streaming replication feature built into <productname>PostgreSQL</> 8.5

onwards; see <xref linkend="warm-standby">.

A PITR standby server can be kept more up-to-date using streaming

replication.; see <xref linkend="streaming-replication">. For

warm standby information, see <xref linkend="warm-standby">, and

for hot standby, see <xref linkend="hot-standby">.

</para>

</listitem>

</varlistentry>