Advice on migration without down-time

Hi guys,

due to the wrong initialisation of PostgreSQL data dir (which
generates 'invalid multibyte character for locale'), I need to migrate
approximately a 90GB database system on PostgreSQL 8.2.3. There is no
replication system set up, yet.

The rawest solution is to:
- stop the server from updates,
- perform a backup with pg_dumpall (the daily bzipped dump all file is
approximately 4GB)
- isolate the server (no incoming TCP connection allowed)
- stop the server
- rename the data dir and the tablespace directories
- reinit the data dir with the correct locale
- create the empty tablespace directories with proper rights for the
postgres user
- restore the whole backup
- restart the server

Of course, this solution is time consuming, given the quantity of
data to be restored (90GB).

I was wondering if you have ideas to propose. I imagine using
replication (Slony-I?) could be a viable option, assuming that the
different locale for the data dir of the two database servers does not
influence the results. Using a slave DBMS could limit the down-time.

Thank you for your attention.

Cheers,
Gabriele
--
Gabriele Bartolini - Istruttore Informatico - Comune di Prato
Sistema Informativo - Servizi di E-Government e Open-Source
g(dot)bartolini(at)comune(dot)prato(dot)it - www.comune.prato.it
<http://www.comune.prato.it/> - www.htminer.it <http://www.htminer.it/>