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<p class=MsoNormal>I just read this page: <a
href="http://www.postgresql.org/docs/8.2/static/continuous-archiving.html">http://www.postgresql.org/docs/8.2/static/continuous-archiving.html</a><o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>And it made me wonder whether this mechanism of continuous
archiving and point-in-time recovery (PITR) can be used for replication.
In other words, Postgres already generates write-ahead-log files for all
operations. If you can transmit those files to another machine and replay
them, continuously, then you have a form of replication.<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>But, it’s not clear if this is possible. The
article linked above talks about doing continuous archiving, but it doesn’t
talk about doing continuous recovery. Instead, it talks about doing a
single point-in-time recovery. Moreover, this recovery requires the
target (“slave”) machine to be offline during the recovery process.<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>Does anyone know whether it’s possible to use Postgres’
archiving and PITR for replication?<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>By the way, if it can, it seems that:<o:p></o:p></p>
<p class=MsoListParagraph style='text-indent:-.25in;mso-list:l0 level1 lfo1'><![if !supportLists]><span
style='mso-list:Ignore'>1.<span style='font:7.0pt "Times New Roman"'>
</span></span><![endif]>It would have the advantage that various operations are
handled in a more natural manner than with Slony (e.g. DDL)<o:p></o:p></p>
<p class=MsoListParagraph style='text-indent:-.25in;mso-list:l0 level1 lfo1'><![if !supportLists]><span
style='mso-list:Ignore'>2.<span style='font:7.0pt "Times New Roman"'>
</span></span><![endif]>It would have the disadvantage that you can’t be
choosy about what to replicate – you get the entire DB cluster, or
nothing at all.<o:p></o:p></p>
<p class=MsoNormal>Is that correct?<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>Thanks!<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>--Shahaf<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
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