Re: PostgreSQL clustering (shared disk)

Hi,

On Thu, 2007-08-16 at 09:42 +0300, Mikko Partio wrote:
> The idea would be that the cluster programs with gfs (and HP ilo)
> would make sure that only one postmaster at a time would be able to
> access the shared disk, and in case the active node fails the cluster
> software would shift the services to the previously passive node.

AFAIK, it is the fence device that will prevent the postmaster access
from the failed node. RHCS will just switch the servers.

> What I'm pondering here is that is the cluster able to keep the
> postmasters synchronized at all times so that the database won't get
> corrupted.

Keep all the $PGDATA in the shared disk. That would minimize data loss
(Of course, there is still a risk of data loss -- the postmasters are
not aware of each other and they don't share each other's buffers, etc.)

Regards,
--
Devrim GÜNDÜZ
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