Daniel Duvall wrote:
> While "clustering" in some circles may be an open-ended buzzword --
> mainly the commercial DB marketing crowd -- there are concepts beneath
> the bull that are even inherent in the name. However, I understand
> your point.
>
>>From what I've researched, the concepts and practices seem to fall
> under one of two abstract categorizations: fail-over (ok...
> high-availability), and parallel execution (high-performance... sure).
> While some consider the implementation of only one of these to qualify
> a cluster, others seem to demand that a "true" cluster must
> implement both.
>
> What I'm really after is a DB setup that does fail-over and parallel
> execution. Your setup sounds like it would gracefully handle the
> former, but cannot achieve the latter. Perhaps I'm simply asking too
> much of a free software setup.
>
> Thanks for your response.
>
Also consider the PITR and some work I did last year:
http://archives.postgresql.org/pgsql-admin/2005-06/msg00013.php
With PITR you can have one or more remote machine/s that
continuously replay log from main, and if the main crash
the "mirrors" can come out from their reply and go "on line".
At that time was not possible connect to a "replayng" engine
to perform ( at least ) queries, dunno if this changed in 8.1
BTW, did someone go further with that idea? If not I'd like rewrite
that stuff in C ( I do prefer C++ ).
Regards
Gaetano Mendola
