WAL backup

Hi all

I'm not sure I understand

    http://www.postgresql.org/docs/8.3/interactive/continuous-archiving.html

My problem:

    I've huge database ~ 1To (soon 2 To) and I need backup.
    I can use pgdump because it's too long to do the backup.
    So I like to use «continous-archiving».

For the continuous archiving I do

    Modifying postgresql.conf with :

        archive_mode = on
        archive_command = 'cp -i %p /databases/Archives/%f </dev/null'

    restart postgresql

    after that I make a big backup:

          psql -c "select pg_start_backup('complete_backup');"
          rsync -av /databases/pgsql /databases/Archives
          psql -c "select pg_stop_backup();"

    before this moment I use «continuous-archiving» by put in my crontab
    something like (every hours)

        rsync -av /databases/pgsql /databases/Archives

is that correct ?

And more important : How long I can keep this the rsync ? I mean after how
long it's good to make a new «big backup» ?

Regards.


--
Albert SHIH
SIO batiment 15
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Mar 28 jul 2009 09:23:23 CEST