Message-Id: <4FD1FC0B020000250004821F@gw.wicourts.gov>
Date: Fri, 08 Jun 2012 13:20:11 -0500
From: "Kevin Grittner" <Kevin.Grittner@wicourts.gov>
To: <pgsql-admin@postgresql.org>,"sgm" <sgm277@yahoo.com.cn>
Subject: Re: Question about PITR backup
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sgm <sgm277@yahoo.com.cn> wrote:
 
> I have a question about PITR backup in a single server, the method
> is make a base backup, and backup the WAL archive log(eg, every
> day at 11:30 pm). But if the OS' harddisk is broken(eg,14:00
> pm),the system can't start, we have to recover the database on a
> another server using the base backup and the WAL backup,so in this
> case suppose that we only can restore the database to yesterday's
> 11:30 pm state, am I right?
 
You can't recover to a point past your last available WAL record.
 
> I want to backup the pg_xlog folder every minute by crontab but my
> concern is that the data inconsistent, because the lastest log in
> pg_xlog is being updated all the time, am I right?   Any
> suggestions?
 
Use streaming replication?  Or at the very least, set a short
archive_timeout value and copy from the archive target location
frequently.
 
-Kevin